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yukonho
02-18-2004, 01:50 PM
My first machine is very cool. I am making a lot of things on it and use it daily for some production where I have actually paid for the machine with what I make! Very cool.
I want to make my second machine now that I have a better understanding of how these things go together. This machine will be more suited to the parts I actually make, not the ones I thought I was going to make!
Requirements are....
-16" X 8" X-Y travel
-3" Z travel
-As rigid as possible with MDF as main material.
-Potentially made from steel, (I can mig and Arc weld) or Aluminum but only if it is truly possible to make a square and true machine with the facilities I have and within budget.
-I am OK to go with rollerblade bearings and gas pipe, but need a better system than I am using now. I use gas pipe and rollerblade bearings mounted on 90 degree aluminum with bearings on all 4 sides. It is not adjustable to get the bearings riding perfectly on the pipes. Need a better way.
If I can get liniear ways for cheap then I will go that way.
-Dremel tool or Dremel Advantage for spindle.
-Enclosure.
-Probably go with a better leadscrew system than I am using which is 1/4-20 allthread and HDPE nuts. But honestly, it is pretty good surprisingly.
I am thinking of having a fixed Gantry for the 16" Y and moving table for the 8" X axis.
I need suggestions for the ball bearing and gass pipe ways, wether or not the fixed gantry and moving table concept is best for my needs, and if I should toy more with the idea of using steel.
Mostly I will be cutting wood, and possibly some G-10, I use xylotex board and nema23 steppers.
Thanks everyone, your input can help me make the perfect machine for my needs.
co

Ken_Shea
02-18-2004, 02:13 PM
Here is a link to a thread on this forum, may be of some help.

http://www.cnczone.com/showthread.php?s=&threadid=2066&highlight=black+pipe (http://)

freezer
02-18-2004, 02:33 PM
I just got in my rails. I went with some drill rod:

http://www.use-enco.com/CGI/INSRIT?PARTPG=INSRAR2&PMAKA=408-0061&PMPXNO=94762

I also got:

http://www.use-enco.com/CGI/INSRIT?PARTPG=INSRAR2&PMAKA=325-7585&PMPXNO=5873921

but I dont think i am going to get the bearings to work the way i want. so, i am planning on using the rollerblade bearings on the drill rod... It is much smoother than gas pipe anyway but more expensive....

yukonho
02-18-2004, 03:24 PM
Thanks guys.
ken_shea, that link doesn't work. Can you try again?
co

Ken_Shea
02-18-2004, 04:05 PM
http://www.cnczone.com/showthread.php?s=&threadid=2066&highlight=black+pipe

yukonho
02-19-2004, 09:29 PM
After following one of the links in one of the threads you guys provided, I have pretty much settled on a design.
http://www.cnczone.com/showthread.php?s=&threadid=1356
I loved this torsion box idea and I am going to use it for my x and y axis. If someone can let me know how to post a picture of my autocad drawing, I will post it here. I like the drill rod idea, but I dont like the extra shipping and duty to get it to Canada. Does anyone know of suppliers north of the border? I am going to use rollerblade bearings still, not the bushings.
co

Mr.Chips
02-20-2004, 12:17 AM
I liked that torsion design too, strong and light. But he said he would make holes in it to lighten it even more.

I'm still working on my machine, slow going it was cold here the past couple of weeks, but nice this week. Slowed down with the metalwork of the Z axis. Woodwork has been my hobby, not done much with metal, but am forced to learn.

Having a working CNC will really be an asset iin building the 2nd.

Keep posting your progress.
Hager

ballendo
02-20-2004, 02:10 AM
Hello,

Just a note or two on torsion boxes.

They get their strength from the SKIN and the glue line TO THE SKIN. A torsion box without a skin is NOT a torsion box! And also not very strong, relatively speaking.

Next, if you ARE going to use a torsion box construction, do yourselves a favor and lighten it up! Using 1/2" inner parts and 1/4" skins (or even 1/4" for everything) will be about the same strength, but obviously MUCH lighter. FWIW, the only reason to use the thicker inner material is it makes them a bit easier to fasten together. (you DO want thicker material at fastening points; or waht an aircraft designer might call "hard points".)

The design shown uses eggcrate construction, which is fine. But NOT necessary for strength. You can build these things MUCH more easily using butt joints. Use long strips one direction and short squares/rectangles the other. No fancy joints necessary...

Ian Kirby first brought torsion box construction to the woodworking crowd through an article in Fine Woodworking magazine. You can look up his article if you want to hear what I'm saying from a "better" source. (FWIW I have used torsion box construction for years in furniture, and ALSO in my first CNC machine, back in '89...)

Modelers might realise that once they put the skins on their airplane wings, everything stiffens up. Same principle... (and think how thin those parts are!

Another example of torsion box construction we should all be familiar with is hollow core doors... Most of those use cardboard! for the inner parts, with 1/8" skins. Try and twist one! So you see, you don't need the thick, heavy materials to use torsion box design:D

Ballendo

ger21
02-20-2004, 06:38 AM
Ballendo, the pictures he linked to are my machine. It IS a torsion box, I just didn't have the skins attached in the pictures, as I was just test fitting everything together. I have a question for you regarding weight. Is it better to have the lightest possible gantry, as was my original thought, or would a heavier gantry help to dampen some of the vibrations. I know the lighter one will have faster acceleration, but I also thought about filling the torsion box with possibly sand to absorb the vibrations. I'd like to here your thoughts on this, as you seem to have been around the block the most times. :) Thanks.

Gerry

ballendo
02-20-2004, 08:59 AM
Gerry,

That is a GREAT question!

Welcome to the wild, woolly and wonderful world of machine design:D

You want both...

This is an example of the sort of tradeoffs ALL machines require. The best machines are those which choose the answers "correctly". Correct-ness is determined by the design aims and goals, moderated in the real world by physics and price.

Huh?

Ya gotta choose for yourself which is more important, based on your needs and expected results. Factoring in the price you can pay--both monetary, and what the economists call "opportunity cost"--Which just means if you're doing one thing, you can't be doing something else...

Is there a way out? Well, can you increase damping without increasing weight? How would you do that?

It's best to have the STIFFEST gantry you can, at the lightest weight at which the required stiffness can be maintained.

Nowadays, stiffness has replaced the old standby of mass in commercial items in many arenas. The places where mass is still used relate to cost, or customer acceptance. Down side of stiffness is that you will have a very specific resonant frequency. If this is in the "wrong" place, you'll be cursing:) Think aluminum softball bat versus wood...

So now that I've "engineered" all over the place, let's talk specifics: Can your drives accomodate the added weight, and still run the gantry at your desired speed? If not, i'd look at the "way out" mentioned above...

Hint: there ARE materials which could provide effective damping that don't have the weight of sand. But they're generally expensive.

Ballendo

P.S. Personally, I'd go for stiffness, and light weight.
(THEN I'd deal with any resonance issue which "spring" up -pun intended:)) There are other places you can improve stiffness first, IMO. See below.

P.P.S. Another question: Does the sand continue to "absorb" vibrations, once it is fully packed--FROM vibration? Does it ever GET fully packed? If it does, is it still sand? (functionally speaking)

P.P.S. I saw the "corners" to accomodate your intended skins in the photos. Only commented because others may not know or take the time to know what a torsion box really means... It might not surprise you to find that many will look at the picture and decide torsion box means "eggcrate half lap construction"...

P.P.P.S. Wanna make your machine stiffer and add adjustability too? replace the single 1/4 angle with 2, and lose the brass bearing spacer/extenders. By moving the one or the other of the angles, you can dial in the y slide--and it's "carried" z. You "would have" also had shorter distance between the top and bottom of your y/z sliding parts. And so a shorter gantry moment. Now you could just increase the thickness of one or both of the top or bottom. Could even make a torsion box with the added space!

P.P.p.P.S. For others duplicating your machine, I'd replace the aluminum with an upper torsion box; or at least add vertical stiffeners. Is the aluminum epoxied to the BB ply? If not, do so. IMO,that is. It will allow the alum to add the stiffness it can. Which if its not glued is not what it "could be".

What's the overall travels of the machine?



Originally posted by ger21
Ballendo, the pictures he linked to are my machine. It IS a torsion box, I just didn't have the skins attached in the pictures, as I was just test fitting everything together. I have a question for you regarding weight. Is it better to have the lightest possible gantry, as was my original thought, or would a heavier gantry help to dampen some of the vibrations. I know the lighter one will have faster acceleration, but I also thought about filling the torsion box with possibly sand to absorb the vibrations. I'd like to here your thoughts on this, as you seem to have been around the block the most times. :) Thanks.

Gerry

buscht
02-20-2004, 09:23 AM
I have used the kind of insulation foam that comes in an aresol can to fill up the inside of a torsion box to improve the dampening.

You need a pretty airtight box though, otherwise the foam squirts out all over.

yukonho
02-20-2004, 09:31 AM
Wow, a guy gets a good nights sleep and wakes up to find all this!
Questions and answers.
First, I am aware that the skin is where the strength comes from (I am an airplane guy) I plan on using 1/4" skin on the Y box and 1/4 on the bottom of the table and 1/2 or 3/4 on the top of the table for fixturing purposes. I had planned to fill the boxes (of the eggcrate) with ground up tire material. I thought about great stuff foam, but I dont think it will absorb the vibes nearly as well, and I have access to the tire stuff.
Regarding one of your p.s' Could you please further elaborate on
--"Wanna make your machine stiffer and add adjustability too? replace the single 1/4 angle with 2, and lose the brass bearing spacer/extenders. By moving the one or the other of the angles, you can dial in the y slide--and it's "carried" z. You "would have" also had shorter distance between the top and bottom of your y/z sliding parts. And so a shorter gantry moment. Now you could just increase the thickness of one or both of the top or bottom. Could even make a torsion box with the added space! "--
I cant picture what you are saying here.
I am quite pleased because I had already settled on many of the things suggested here. Thinner eggcrate, simple rectangular sides and simple cross blocking with a thin skin.
Can anyone let me know how to post a screen picture of my autocad drawing?
co

ger21
02-20-2004, 10:01 AM
Ballendo, it's not done yet, because for some strange reason, my wife insists that I finish the whole house remodel I started 3 years ago. :) Almost there, though.

The X-axis will be about 60" long with a little under 4 ft. of travel. The gantry is about 40" wide with about 32" of travel. Z travel is about 8". I'm still deciding how high to make the ganty above the table. My original drawing has it around 5 1/2". I wanted to be able to reach the table with 1" of cutter out of the collet, and with 3" out of the collet, have the cutter clear the gantry. The gantry will be driven by a Xylotex driving 2-250oz-in PacSci steppers turning 2 start 1/2-8 acme.

Gerry

PS
I read a while back that you were writing some CNC books, what's the status of those? Thanks.

ger21
02-20-2004, 10:05 AM
From AutoCAD you can export a bmp. Then you'll need to convert it to a jpg as the file will probably be too big. Under File>Export.

Gerry

yukonho
02-20-2004, 10:54 AM
OK
Light blue is the endplate. Red will be several of these along the length of the tube or drill rod or whatever I end up using, yellow is torsion box/table. Dark blue is aluminum angle and bearings. I have some 1/2" X 1/8" aluminum bar shown that will be attached along the edge of the table to align the angle.
comments?
co

yukonho
02-20-2004, 11:03 AM
My only question at this point is how do I get some adjustability in there to make sure the bearings ride perfectly on the rods and everything is tight and aligned?
co

ger21
02-20-2004, 12:23 PM
How about running some bolts through the red pieces to push the pipe together. I built mine the opposite way because it's easier to hold the pipe in place. I just looked again, and on your endplates you can make the 4 bolt adjutment blocks that you see here all the time. And after everything is adjusted, mount the red pieces to hold everything from moving.

Gerry

yukonho
02-20-2004, 01:10 PM
I did something similar to yours for the Y axis. With the X, I wanted the rigidity of the torsion box for the table. I thought about mounting the rails to the box and having the bearings stationary, but decided against that, no advantage.
I am wondering if I should just make it all rigid, no adjustments at all. If I cut it all on my CNC it should (I hope) be accurate enough. Other than that, your idea of aligning it all first and then mounting the support blocks seems best. For some reason I dont like those 4-way chucks. Cant say why really, I would rather have a precise and accurate press fit. I am certain I can get the holes cut in the end plates within a couple thou.
Did you thread your Al angle to bolt them in place? I plan on using 1/8 angle and am worried about threads stripping. If I mill a flat and use a bolt with a flat enough head I can just bolt them in place from the outside.
Keep suggestions coming. Especially about the table concept.
co

InventIt
02-20-2004, 01:17 PM
in respect to moving table designs...

Anyone ever think to mount the pipe to the edge of the table and the roller bearing to the frame of the machine? Just the reverse of what your drawing shows. That way the support (bearings) are always under the gantry.

Would that work?

yukonho
02-20-2004, 01:23 PM
That is how it is done on moving gantry designs. This is a moving table design. I thought about it, as I mentioned earlier, but decided against it. It just doesn't feel right for some reason. Possibly because a large part of the table would be unsupported as you move away from the centre of travel. It would also be somewhat more difficult to allign the rods. Wonder what others think about this...
co

ger21
02-20-2004, 02:22 PM
Look at the second picture in my thread. I milled a flat for the bolt head. I didn't use the cheap 1/8" angle. I have 1/4" x 1-1/4" 6061 angle. The 1/8" angle you can twist in your hands, the stuff I got is rock solid, much stronger.

Gerry

yukonho
02-20-2004, 03:55 PM
I have had good success with the 1/8 angle. Over 8" I can not twist it by hand. My machine is significantly smaller than yours is, and I run a dremel for a spindle. I will consider the 1/4". I am not sure I can use it with 1" rails. There would not be enough room on the back side of the aluminum angle for the heads of the bolts that mount the bearings. I will have to check this in CAD.
co

yukonho
02-21-2004, 01:53 PM
I must say I am very happy with the design progress thus far. Going with a fixed gantry and moving table has allowed me to design an integral enclosure. I would love to use some "real" linear ways, but cost is just too much of a factor. I am convinced that this design will be what I am after though. Here is a side view in 2D

yukonho
02-21-2004, 01:56 PM
The integral enclosure will help increase rigidity even further. Cant wait to put the saw to the MDF on this.
co

pminmo
02-21-2004, 03:51 PM
Originally posted by yukonho
I must say I am very happy with the design progress thus far. Going with a fixed gantry and moving table has allowed me to design an integral enclosure. I would love to use some "real" linear ways, but cost is just too much of a factor. I am convinced that this design will be what I am after though. Here is a side view in 2D
One comment. I've had a simalar thought on my second router, Posting a picture here. My thinking is a cutout that would allow long pieces to be cut along the long axis.

Phil

pminmo
02-21-2004, 03:54 PM
front view

ballendo
02-21-2004, 05:41 PM
Hello,

Instead of using 1-1/2 x1-1/2 x 1/4 thick alum angle, and mounting the screws which hold the bearings in the middle, away from the corner; and using long screws to hold the bearings with brass spacers, further increasing the possibility and probability of flex...

Use 3/4 x3/4 x1/4 aluminum angle. Drill the holes for the bearing screws as close to the corner as you can. Since the corner is the strongest part. With skatewheel bearings we're using 5/16 bolts (or 8mm), so the closest you can get to a 1/4 wall corner is 5/32 plus 1/4, which is 8/32, so the total is 13/32. Add a 32nd for clearance, and you're at 14/32, or 7/16.(11.25mm)

Already, with just these two changes, things will be much stiffer (keep in mind that with his large diameter rails, he might NEED the larger angle. The point is to use the smallest angle you can, and drill as close to the corner as you can.

Next, mount the bearings as close to the angle as you can. I usually buy a bunch of hardware store washers, and rub 'em over some fine sandpaper to get rid of the high/rough spots. Then I get an egg carton, and with my dial calipers, start measuring the thickness, sorting the various thicknesses into their own piles. (In a hundred washers, I'll almost always "prove" the bell shaped curve of statistics:D) That way i have cheap "calibrated" washers for when I need them all the same, AND for when I need one thicker or thinner for "shimming" purposes...

These are all just basic engineering principles.

The next part was in reference to HIS large diameter rails specifically. He has "room" to use TWO pieces of angle, with only TWO bearings on each piece (instead of one angle with 4 bearings). This way you can adjust the movement of the carriage(s) very precisely.

I've seen other posts which mention using the 4screw rail end mounts to dial in the machine, but this won't dial in everything accurately. you need to dial in the RAILS, THEN dial in the carriages TO the rails, if you want to have planar movement of your axes. (Please remember that you don't HAVE to have planar axes to make stuff. lots of machines here are examples of that truth. But they're not truly accurate, and it's fortunate that the parts made don't require them to be...)

Hope this helps,

Ballendo


Originally posted by yukonho
.
Regarding one of your p.s' Could you please further elaborate on
--"Wanna make your machine stiffer and add adjustability too? replace the single 1/4 angle with 2, and lose the brass bearing spacer/extenders. By moving the one or the other of the angles, you can dial in the y slide--and it's "carried" z. You "would have" also had shorter distance between the top and bottom of your y/z sliding parts. And so a shorter gantry moment. Now you could just increase the thickness of one or both of the top or bottom. Could even make a torsion box with the added space! "--
I cant picture what you are saying here.
co

yukonho
02-21-2004, 07:18 PM
I follow your ideas.
It is important to keep the bearings center line normal to the rod they are rolling along. Keeping this in mind, if you drill the mounting holes closer to the corner of the Al angle, then your bolts need to be longer (the bearings have to be further from the aluminum angle) to keep them normal to the rod. This increases the moment arm of the bearing on the aluminum. I have not done the FBD or the math, but I believe that the forces would be very close for either setup.
My measurements of the bolts I use suggest I can make the centre of the bolt hole 1/4" from the inside face of the aluminum angle, but then, like I stated earlier, my bolt would have to be longer, 6 of 1, half dozen of the other.
For the record, I am still looking for inexpensive linear ways to use instead of these rollerblade bearings. It will save so much time in setup and alignment and building and everything.
I like the open side idea. The front view doesn't register with me for some reason, I cant figure out what is what. I have designed my machine for specific purpose, and I dont envision making anything bigger than what I designed it for. For the record, my machine now is 12" X 36" travel and I have never used it for more than 10" travel.
Also, I want to keep this fully enclosed for noise and dust reduction. I am very happy with the enclosed design. I think it will look very cool when done.
co

ger21
02-21-2004, 08:05 PM
Ballendo, like yukonho says, I designed it with the centerline of the bearing on the centerline of the tubing. The 1/4" thick 1-1/4" angle is really stiff. I can't flex a 4ft piece in my hands. The 1/8" angle I can twist a 1ft piece in my hands. The way I have mine set up, the bearings are in compression on the tubing, and if there were any flex, the compression takes it out.

Gerry

ballendo
02-21-2004, 08:34 PM
Hello Ger and Yukon,

Would you say a full size 1500 lb. cast iron Bridgeport mill is stiff?

Because with an indicator in the spindle it only takes "finger" force on the table, ram, or quill to move the indicator!!!

I'll bet you'd have similar results with the 1/4" alum angle:)

As to the "normalling" of the bearings. Yes, when you use ONE piece of angle, you're limited. I was talking about using two, so adjustments could be made. Also, the strongest part of the BEARING is ALSO near "its" corner...

If we're gonna talk about how to make an inexpensive machine stiff, we can't just let all these little bits that "can't be felt" stack up against us... :D

Ballendo

P.S. Hopefully the BP mill example shows that there IS flex. Always. So the EMT bends a bit, the bearing itself bends a bit. The shaft it's on bends a bit. The 1/4 aluminum bends a bit. The mdf/BB ply bends a bit...

The compression "pre-loads" your assembly. But that doesn't necessarily change much in your result once you start cutting and dynamic loads are flying around. Then it's about moments, and levers, and material deformations, surface hardness, contact areas, PSI, etc...

Both your machines are good. Please don't infer anything less from what I'm writing. But they can be better, and without costing more... I'm just trying to point out possible directions.



Originally posted by ger21
Ballendo, like yukonho says, I designed it with the centerline of the bearing on the centerline of the tubing. The 1/4" thick 1-1/4" angle is really stiff. I can't flex a 4ft piece in my hands. The 1/8" angle I can twist a 1ft piece in my hands. The way I have mine set up, the bearings are in compression on the tubing, and if there were any flex, the compression takes it out.

Gerry

ballendo
02-21-2004, 08:43 PM
Hello,

Forgot 2 things:

Skewing the bearing intentionally will give a "wiping" action which helps keep the rails clean, at the expense of some additional wear and slightly greater axis force required. Just a bit, don't
overdo it! And you can rotate your rails, if needed to deal with wear, right?

Next, with bearings mounted at 45's and running centerline on centerline, the part of the bearing "above" this centerline contact point becomes a trough for all the swarf, dust and chips that fall from above. Which the bearing then grinds into the rail.

If you plan it right, the bearing corner can very nearly meet the tangent of the rail on the upper contact points. This will reduce the "trough" effect considerably. AND, as I mentioned just a moment ago, the bearing is stronger that way too!

Ballendo

ger21
02-21-2004, 08:45 PM
I'm not arguing, keep the advice coming. Until I get the whole thing done I won't know how much it will flex. I understand exactly what your saying, I'll just have to wait and see. And if it's not stiff enough, then I get to build a better one. I've got some ideas for making up some composite parts for the next one.

Gerry

PS. I run a point to point machining center at work with a 9HP router, and I've seen some flex there. So I do know that even big steel machines aren't as stiff as they could be. It's relative I guess, kinda like precision and accuracy? :D

Mr.Chips
02-21-2004, 11:15 PM
For what it's worth I used steel angle iron for my bearings, much more rigid than alum, still used a bolt and nut rather than threading the angle iron.
Hager

yukonho
02-22-2004, 12:05 AM
I think I will stick with running the bearings centred and running normal to the pipe. Seems easier to set up that way. My tools are limited, so I can not use steel angle.
My design is essentially done now, and I am going to put together my cutlist and BOM so I can get going on it Monday. Fortunately Home depot has that panel saw so if I get my list together I can pay a couple of bucks and have most of my wood cut to accurate dimensions then just a couple of cross cuts with the miter saw and away we go. I am going to cut the rod supports on my CNC and I am going to try to do the holes in the angle Al on the CNC too. I will probably just end up drilling pilot holes though and hand drill them to full size after.
Speak now if you have suggestions please, the end is nigh!!
co
P.S. I am still really happy about the enclosed design. I think it looks sweet.

yukonho
02-26-2004, 03:13 PM
I am going to use one of each of these delrin nuts on each end of my table. Having one on each end should give me an anti backlash effect.
co

yukonho
02-27-2004, 10:58 AM
Y axis torsion box pictures. I am going to fill the cavities with ground up recycled tires.

yukonho
02-27-2004, 10:59 AM
Love the torsion box idea, thanks for the link to that thread. Makes for a compact and super strong axis.
I am going to do the same on the table. (moving gantry design)

Mr.Chips
02-27-2004, 07:35 PM
yukonho
I saw an article somewhere about filling voids such as you have with a mixture of sand and oil. It does two things, reduces viberation and absorbs sound. You could even fill the pipes.

Nice torsion box, What size pipe/conduit was it made for?
Hager

High Seas
02-27-2004, 10:09 PM
Is it just me - or has someone else noticed a missing post here too?
Earlier today there were several posts following Hager's (Mr Chips) that wrote about using sand including a reference to using recycled rubber tire bits for dampening in the internal areas of the torsion boxes, several references to sand in the chanels in aluminium extrusions, a reference to speakers and dampening - and another reference to riding motorcycles and lead shot in the handlebars.
Is the system dropping stuff - is my system acting up - or have these been moved? The post numbers are all in sequence and the latest shown on this thread is 37 - then this one.
Just trying to give as much info here if there is a sys dropout - else I should stop repainting this house?!!!! Nawww its not fumes -.

On the other hand - if they've been moved - how would I know that - would it show on the "New Posts Roster" on sign on?

Jim

pack rat
02-27-2004, 10:17 PM
Yes you are correct High Seas, Also I think that yukon said that he has access to rubber and that he is going to use it due to its density. The paint that you are using must be latex because your memory is correct:D

Mr.Chips
02-27-2004, 11:54 PM
Think you may be refering to his other thread, I gave the same comment on both threads.
Hager

yukonho
02-28-2004, 09:01 AM
I dont think there are any missing posts in this thread, but I definately remember reading about the sand and oil and such in the other thread. hmmmmm.
Anyway,
I cant use sand and oil in this one because it is made from MDF, and I think it might have a problem with the oil :o
I have access to the rubber stuff and it is as dense as, well, tires which should damp out the vibes some.
I never thought of putting it in the pipes, and that is a good idea,I will do that too although I think concrete would be a better choice for the pipes.
The box is designed to accept 1" gas pipe which means the cutouts are actually a bit bigger than 1". I considered drill rod, but went with the pipe because a)I already have it, and b) shipping stuff here from the US takes a long time in customs (my last order was 14 days) and I get completely screwed in customs charges to the tune of almost 50% of the value of the order.
So Gas pipe it is.
The torsion box is nearly done, but I have to make 100% sure it is flat and true when I close it up. Any warp will stay when I attach the other side.
I really love the idea though, lighter and stronger is a winning combination.
co

yukonho
03-17-2004, 06:36 PM
Well, I have not done much for the last week. I made the table and the ends and rail supports for the new machine. My rubber has not arrived yet, so I can not finish assembling the tortion boxes. It should be here tomorrow so I can do more soon.
It is nice having a CNC to make another one. It is still very slow, but at least it is very acurate.
I believe I will go with 3/8-13 threaded rod on this one. That should get me 65 inch/min rapids wich will be pretty good for 10"X 20" of travel I have. 20 seconds corner to corner as opposed to with 1/4-20 rod.
Does anyone know if I can run this high of a pitch with 160 oz/in steppers? I hope so.
I ordered the couplers from stepperworld, I will have to somehow turn down the end of the rod to fit the coupler.
pics to come
co

johntbyrne
03-17-2004, 06:43 PM
Hey Colin,

I don't know if the rubber will make it there by tomarrow. I just checked and it's in NY. I guess this is where it will make it to customs. If I did things right it should get through there tomarrow and make it to you on Friday, at least I think.

My fingers are crossed
John

johntbyrne
03-17-2004, 06:49 PM
BTW, do you think your first mill has enought "umph" to carve Maple if the feed rate is slow? I'm thinking of making my mill much like your second machine but with steppers sized like your first machine. If so just curious if I could carve a guitar body top.

ger21
03-17-2004, 07:14 PM
Does anyone know if I can run this high of a pitch with 160 oz/in steppers

I've seen a lot of machines here use 1/2-10 acme with 100 oz-in motors. Why don't you try 3/8-10 or 3/8-12 acme? This will give you a little more speed and you can get better quality screws.

Check here: http://www.mscdirect.com/PDF.process?pdf=3888&Section_Id=451&Keyword=Y

THe ones on the bottom of the page are very good quality screws - nice and smooth threads. And the 3/8-12 is only $11.65 for 6ft.

Gerry

yukonho
03-17-2004, 08:01 PM
I am using the same steppers on the second machine. The first one is not rigid enough, but I am quite confident the second one will be much more rigid and should easily cut much heavier material because it is smaller and the rails are supported, and the Z axis is a "real" linear way.
On my machine you wouldn't be able to fit the guitar body, but if you went just big enough with your machine you should be able to keep it rigid enough, what does it need to be, 14" X 25" ?
As far as enough power with the steppers, I use 1/4-20 threaded rod and it is plenty strong. 160 oz/in torque transmitted through 20 tpi is a big mechanical advantage. I am going to try 3/8-13 on this machine, I hope I dont lose too much force with that.
I had not checked on the rubber, I was guessing. It is not like I have a bunch of time these days to put into the machine anyway, a bit here and there when I can slip it in.
Although I know what time is like for you, so I cant complain.
co

yukonho
03-17-2004, 08:07 PM
Honestly, the biggest problem is that when I order something from the US it either takes a long time to get here, or it costs me out the nose for customs fees or both. I have tried to find canadian sources but little luck.
I will keep looking though.
co

johntbyrne
03-17-2004, 09:01 PM
time ...... what is that? i seem to kind of remember.

seriously, bought air guns and compressor. Started remod for real. Bought front door (mahogony) today. On sale, have to store for a month or two. On top of all this, Louisiana released grant money last week so new plant construction just kicked off. Finally, part I went to Florida to test failed. Had to redesign and will have to return in a couple of weeks. BTW, I didn't design the first part.

I think the cnc router will be a mental diversion for a few months. I suspect my heli frame designs will be too. Just no time. In fact, got to get back to work on house right now so have a great one.

John

BTW, reason for size is a body is something like 16" by 20" and fret board is I think 21" long. I'd like to mount both in machine. I'm going to keep eyes open for parts during next few months and simply get stuff during this time. I can build after the plant is built and house is done. I suspect that puts mill construction around July. grrrrr.

yukonho
03-19-2004, 04:55 PM
My rubber arrived today! Thanks John.
I have been good this week and done a lot of work so I can spend some time on the router tonight.
I hope to get the torsion boxes completely assembled Maybe get the angles drilled for the bearings.
co

johntbyrne
03-19-2004, 06:02 PM
Glad to help. Does this look like the same stuff you saw at the fields?

BTW, could you shoot me some pics of the box with rubber in it prior to closing it up? The owner of the company will get a kick seeing it.

Be good and pull long
John

yukonho
03-19-2004, 07:18 PM
Same stuff used in the fields. Some of the stuff in the fields has bigger chunks though. I will take some pictures for sure.
Thanks again.
Going to play some Open ultimate tonight, preparation for FoolsFest in Virginia in a couple weeks. Playin with the big kids now!!!
co

johntbyrne
03-19-2004, 10:21 PM
cool and COOL

yukonho
03-22-2004, 06:54 PM
I called Igus today. First of all they were very helpful, a real human being answered the phone and they were very patient with my questions and knowlegable.
They recommended against going with the one 80mm N type for the Y axis and suggested the W system instead. It is a much more solid system, and perfectly suited to this application. My 24" Y will cost me about $100 US. That includes rails, 4 bearings and pillow blocks, and a plate that attaches it all together. This is more than the N series, but still very reasonable.
I just have to do some mods to my CAD drawing to make sure everything will fit easily and then I will order them.
There is an office in Canada too, so no border costs.
co

barkster
03-23-2004, 10:46 AM
I'd like to see a picture of you IGUS rail system, looks pretty nice from their website.

yukonho
03-25-2004, 01:14 PM
I did a bit of work on the router in the last couple of days, essentially just filled up the Y axis with rubber and closed it up. Due to time and cash constraints I will probably end up using pipe and rollerblade bearings as I had originally intended. I will still be able to switch over to the other linear ways later if I decide to.
pictures to follow.
co

mhackney
03-25-2004, 08:26 PM
barkster, I am making my first cnc router with igus rails. See http://www.cnczone.com/forums/showthread.php?s=&threadid=3462 (mhackney's first CNC router) thread for lots of photos and my experience with this rail system. (sorry yukonho for butting in! I've found this thread very inspirational for my machine.)

Michael

yukonho
03-25-2004, 09:05 PM
No worries Michael. Glad to hear I have been of some influence!
I just finished the most nerve wracking thing I have ever done on my CNC machine. I hooked up the spindle to be controlled by a solid state relay earlier today, no biggie, but now I just hooked up my Estop button, man I wasn't sure if I was going to blow the board or my computer or what. So I checked my connections 37 times and went for it. Works like a charm! WOOHOO I am one step closer to having a real CNC machine! bring on the tool changer!! kidding. Hopefully I wont have to use the estop often, but it is nice that it is there. (and adds to the cool factor)
co

yukonho
03-25-2004, 09:10 PM
Here are a couple of pictures of the rubber filled y axis torsion box. It is relatively light still, super rigid and I am sure it will be more "dead" than my current setup of unsupported bars and flat board table. The new moving table will get the same treatment. I glued it all together with Elmers Poly-Urethane glue which foams up as it sets and seals any gaps. I didn't want any rubber working its way out of the box.

yukonho
03-25-2004, 09:12 PM
Here is a close up of the filled box. The rubber is ground up tires that was graciously donated to me by a new friend (and fellow old school ultimate frisbee player).
co

balsaman
03-25-2004, 09:15 PM
You had better vacuum before your wife gets home....:)

Eric

yukonho
03-25-2004, 10:26 PM
You must know my fiancee very well!
The place was spic and span long before she got home.
(honestly, she is incredibly tolerant. I have my CNC and my whole helicopter blade business set up in our dining room!)
co

balsaman
03-25-2004, 10:28 PM
Well, That might change once you marry her..;)

E

yukonho
03-26-2004, 08:33 AM
Last night's project. Dont laugh at my BIG RED E STOP button. I couldn't fit the fan inside, but I am only running 24V so it should be OK. I might add it to the outside later.

yukonho
03-26-2004, 08:37 AM
backside.
I cut the front and back panels on my CNC router, of course.
One switch is main power, other is switched to an outlet on the back for a light. The other outlet is switched by software to turn the spindle on and off. Lights on the front are for main power and spindle on.
co

johntbyrne
03-26-2004, 11:25 AM
Looking Good. Do you have enough rubber to do the table and this box? I have about 3 million more pounds in my warehouse.

yukonho
03-26-2004, 11:59 AM
More than enough left, John. I will keep that 3 million pounds in mind for my next machine.
co

Gus_452000
03-26-2004, 12:37 PM
Very good stuff,
as to the 'big red stop switch' the women allways tell us fellows that size is not important!
Yeah right.
Like the idea of filling the torsion box with rubber, very clever.
Keep the posts coming, I'm having to start packing up my workshop (due to the fact were moving house) and am having to put all my projects on the back burner, so I'm having to watch you chaps.

all the best

Gus

High Seas
03-26-2004, 06:28 PM
yukonho -- Nice looking control Box! Did you catch my cheapo find on in-line switch at Home Depot? Its red - would kill the power circuit anyway.

for johntbyrne :


Originally posted by johntbyrne
I have about 3 million more pounds in my warehouse.
Those tire bits wouldn't be colored and ready to use as mulch would they? Whooo - wait a minute - I gotta stop workin' on this house remodel project!
Cheers - :cheers: Jim

ger21
03-26-2004, 06:51 PM
Be careful with no fan on that Xylotex, I here they can be pretty sensitive.

Gerry

johntbyrne
03-27-2004, 12:14 AM
Jim, I just finished a system to screen truck buffings for landscaping but we don't do the color part. Selling to someone else for that. Cool looking stuff. If this proves out I'll have rubber in mine for sure. I sure hope it does since I can obviously get all I want and mine will be fresher than this week old stuff you see in the pics LOL.

yukonho
03-27-2004, 02:33 PM
Highseas, I did not catch your find. I will check out home depot Monday.
I will keep an eye on the board, it doesn't get too hot in the open and there is a bunch of airspace in the box so it "should" be OK.
John, I didn't know that "fresh rubber" would be better, can you send me a half a million pounds of the fresh stuff? hehe
co

teilhardo
03-27-2004, 04:33 PM
I'm sorry for being redundant but what exactly is the "torsion box" used for?
-Tei

davesaudio
03-27-2004, 05:23 PM
might be good to have some grommets where those wires
feed thru? - csa/ul/nec etc

yukonho
03-27-2004, 06:15 PM
I will have my pipes running on top and bottom of the torsion box. The box will eliminate any flex of my pipes under the weight of the z axis and cutting forces. I am also using one for the table. It will make the table incredibly rigid but still light.
Yeah, I was thinking of grommets but just didn't have any when I put the box together. They are strain relieved though.
co

yukonho
04-23-2004, 08:54 PM
A couple of hours here and there is all that I have been able to do lately. It is coming along and I am really liking the design more and more.
The torsion box on the X axis along with the enclosed back makes it super rigid. The tortion box is filled with rubber nerds.
The table is a tortion box too and will be filled with the nerds too. The pipes are supported along the top and bottom of the tortion box, and the holes on the sides are oversized. I will add the 4 jaw adjuster idea on both pipes each end. The holes on the y axis are cut with my CNC and are not going to be adjustable. The Y axis pipes will be supported at two spots on each side, and should have no sag at all.
Total travel is 20" X 11" X 4" I have a very solid slide for the Z axis.
I really like the door idea. Should keep the noise and dust way down.
co

yukonho
04-23-2004, 08:57 PM
Nother pic with "door" open

Mr.Chips
04-23-2004, 10:37 PM
Really like your design. The cabnet as you say is really part of the structure, and should keep the sound down too.
Do you plan to put a windshield wiper on the inside? Ha Ha

Good job, looking forward for the next photos.

Hager

yukonho
04-23-2004, 11:36 PM
No windshield wiper, but there will be recessed lights on each side lighting up the work area. Headlights if you will.
I am am really happy with the design. It is built to use for my business, and the work envelope is designed around the parts I make (rotor blades for R/C micro helicopters) The enclosure started as a way to keep the noise and dust down, and quickly became integrated with the structure. I kinda wish I wasn't so cheap and would spring for linear slides. I would rather get a new heli though!
co

Mr.Chips
04-24-2004, 08:36 AM
Well we all have to set our priorities.

Will you hook your shop vac up to the cabinet or have a dust pickup at the cutter?

I haven't heard anyone discuss the dust and the router since it relies on airflow to cool it, or is there even a concern about dust buildup inside the router? Mea by it isn't an issue.

I think we will see copies of your design in the near future. People make a machine then realize that there's a big dust issue. And your design address the dust, and it's an ever stronger more rigid machine because of the integration of the cabinet and frame, not to mention your use of a torsion box design . It also saves money and material, speeds up construction. Etc...

It's like a rectangular/square egg, in design and strength. Name "Square Egg" ??

Regards,

Hager

yukonho
04-24-2004, 10:06 AM
Square Egg, sounds like me in high school! Haaahaha
I have been using a dremel. Dust is not an issue for it at all. The fan inside blows a lot of air and there is no buildup. I want to replace the dremel though because the runout and chatter is unacceptable.
At this time, my toolpaths are short, and I vacuum between each cycle. I have been thinking of a vacuum shoe at the spindle, it would be easy enough to fit and feed through the back of the machine. It would also create a negative pressure in the enclosure to prevent ANY dust from getting out. Trouble is, the vacuum is louder than the router, and with the enclosure it will definately be louder than the router. I need a shop! preferably with a central vacuum located outside of the shop. Funny how many years I have worked in loud environments and still I cant stand noise.
Thanks for the compliments on the machine. I have been thinking of drawing up some plans for it. At this point there are no changes I would make to it, perhaps I will find some by the time I am done building it.
co

mvaughn
04-24-2004, 12:56 PM
Originally posted by yukonho
Nother pic with "door" open

Is it a concern about dust and chips collecting in the trough formed by the Y-axis torsion box?

What about the same dust and chip issue collecting in the lower bearing of the Y-axis. It appears that it will wrap entirely around the tosion box, forming a trough of it's own.

You might have addressed this question previously but I didnt' see it when I was browsing this thread.

yukonho
04-24-2004, 11:31 PM
Good questions.
The top of the tortion box can fill up to overflowing and the bearings will still be above it. The pipe adds another inch to the height there. Underneath, again the bearings are above the bottom. I do plan on putting a cap on each end though to try to keep as much dust and chips out as possible. The gap between the Y axis carriage and the torsion box will be only .125" each side, so not too big. I will be using a dremel an then probably a larger trim router as the spindle. My experience with my current machine is that the chips dont ever get that high anyway. Dust will be more of an issue now that it will be contained though. I will have to pay attention to that and vacuum well and often.
The axis with the torsion box will be called the X axis. This is for a couple of reasons. Number one, it is the longest axis on the machine. Number two, it is much easier to visualise it on the machine when I am drawing up the parts in CAD.
Just figuring out tonight how to fit the limit switches and dust covers for the Y axis pipes and bearings. Stationary plastic plates on each side, just below the table and above the bearings. They will be fixed at the ends and should prevent all chips from landing on the pipes.
co

yukonho
04-24-2004, 11:34 PM
On another look, I could also fill up those trough's with some kind of solid filler. Maybe the cement with polymer added or some other solid material. (epoxy would be too expensive) I could do both top and bottom to add even more mass and vibration dampening.
co

yukonho
05-23-2004, 05:44 PM
A little more work done.
I trial fit the table and it fit perfectly! Rolls nice and smooth on the pipes. Also went to Canadian Tire today to get some spring clamps and came away with a two speed Rotozip!@ Regular 140 (CAD) on sale for 80! I plugged it in and it is quieter than the Dremel! So now I will have a much more rigid spindle that can take 1/8 and 1/4 inch bits, has a 5 Amp motor and two speeds, and is quieter! Should have no problems fitting within the enclosure, it is only about 1/2" longer than the Dremel. I will probably get an aluminum bracket made to mount it.
Also got my Acme 3/8-12 lead screws. Just a matter of balancing time to put it all together. Stay tuned pics to come/.
co

yukonho
05-26-2004, 11:27 PM
Here it is as it sits now.
I am super happy with the design still. I would still prefer to use some real linear ways, but the steel pipe will do very well in this setup, especially supported by the torsion box on the long axis. I made supports for the pipes that support the table, but I am not going to use them. I can put all my weight on it, and I cant see any flex. This must be because the bearings are so far apart and never more than 12 inches from the supported ends.
co

yukonho
05-26-2004, 11:31 PM
Here is the table. Torsion box idea here again. Like the X axis torsion box, I will fill this with my ground up rubber (thanks again JB) It will add mass and absorb any vibrations. The middle boxes will remain empty because that is where my Acme leadscrew will go.
The foam you see in the corners is polyurethane glue I used to glue the box together. THere are a whole bunch of screws holding it together too. I want this thing to be rigid and dead!
co

yukonho
05-26-2004, 11:38 PM
And finally, the bearings for the X axis. The torsion box idea rocks. It completely eliminates any and all flex on the longest axis. I could use a better way to adjust the tension of the bearings, but I will have to settle for shims. These angle brackets will be bolted the same way the ones on the table are. I just drilled and tapped a hole in the corner of the angle, and bolt it through the MDF. They dont take a whole bunch of force, in fact, they pretty much hold themselves in place, so I am not worried about stripping the threads.
The torsion box is not bolted in place yet, (have not exactly figured out how I am gong to do that) I have to align it first, and then attach it securely. I left the gas pipe long so I could use the 4 jaw chuck idea if I need to. Hopefully I wont have to.
Up next, leadscrews and leadnuts!
co

drawbar
05-27-2004, 10:34 AM
Can you give us any details on your Z-axis slide?

yukonho
05-27-2004, 10:54 AM
Bought the z slide off ebay. I got two of them, but only use one for this machine. The other one is collecting dust.
Really robust unit, it says MicroSlides, inc. Westbury NY, there is even a phone number on it, not sure of the area code I think 516 or 518 and 334-4180 I am sure it would be easy to look up the area code.
Model # 2060
I might consider selling the one I have remaining. I got the two for 60, (Shipping was a bunch and cross border fee's too)
Let me know if you are interested and we can work out a price.
co

grempel1
05-31-2004, 03:05 PM
Hi,

This is my first post and since I have been following your journey with interest, I decided to intrude on your thread since much of my design builds upon your experience.

First, I just wanted to comment on the discussion about gas pipe and smooth pipe and so on. Seeking inexpensive and smooth, suggests to me another alternative, namely store fixture clothing rail. This is the chrome-plated pipe that host most men's clothing, expecially suits, sports jackets and coats. It comes in 8 and 10 foot lengths and costs not much more than a dollar a foot. At 1 1/4 OD it also exhibits monocoque characteristics. I would assume that its chrome surface would be considered smooth enough for the purposes at hand.

I am in the process of finalizing the design of my FIRST CNC router and unfortunately I am trying to make decisions about things that I have not experienced. So given your thoughtful overview, I though I would solicit your advice based on your experience. [Besides, I just don't have enough time left to make every mistake that inexperience would suggest]

I am looking to build a fixed-gantry, moving-table router designed to cut deep-relief (z > 8') male, foam plugs. While most cutting involves say, blue foam, on those rare occasions where the foam does not sustain details, the surface is sprayed with something akin to a primer and the detail is rerouted with a 1/32 or so offset. That would represent the maximal side thrust.

I am hoping for a usable table dimension of 36 x 24 inches.

Using 1 1/4 pipe, would you suggest skate bearings or cam followers. What size?

Should the pipe be located at the outer edges of the table as per your design or set under the table, set in say 9 inches from each edge? Should the bearings be set at the edge of the table as per your design or should they be set in say 1/4 of the distance from the edge of the moving table. I assume that since any forces generated by the routing will be lateral rather than vertical, that therefore the orientation of the the bearing sets should also be lateral (like yours) rather than vertical (with the "v" and the bearings above the pipe)

Since my activities will be restricted to routing foam, would you see any advantage to the use of your torsion box rather than a simple table? ? ? On the other hand, given the leveraged force that will occur from the 8" usage z on the gantry itself, would you suggest a torsion box made of wood or the use of square or rectangular metal tubing for the gantry structure?

The workable answers to these questions should get me quite a way toward completing the structure of the router.

Thanks in advance.

Rgds,
Gary Rempel

vacpress
05-31-2004, 05:59 PM
yukonho

nice machine. i like that you accept MDFs weakness and make torsion boxes for everything. i build furniture occasionally and have always thought these mdf machiens here were lacking some of the stiffness of a couch with a good cross-support design...

itll look great painted....

yukonho
05-31-2004, 11:39 PM
Well, it lives.
Machine number two roared to life today. It will need some upgrades in the near future, like a better spindle mount and thrust bearing mount for the Z, as well as there is some backlash on the Y axis and some play in the X. By some, I mean a little tiny bit, but noticeable. The hardest part of using pipe and bearings is getting rid of all the play. I ended up using some hard rubber spacers which work OK, but leave a little flex in the system. Will be looking for a better way in the near future. I think the answer for the X will be an aluminum carriage with adjustment slots built in. It is pretty much impossible to do that with MDF.
Looks like I got the alignment pretty good too, I will have to double check it to make sure.
Speed is up, 74 "/min rapids on xylotex board and 3/8 - 12 Acme leadscrew with 24 V going in. I will be cutting my first parts tomorrow ooeeeee cant wait.
Still have to put the door on and all the little things that make it nicer. Cant really see myself taking the time to paint it, we will see.

yukonho
05-31-2004, 11:54 PM
Grempel1,
If you are going to have such a big table (and that is BIG) you will need to support your rails. I cant think of anything wrong with laying the pipes on the bottom and having your table ride on top of it. If you have a heavy enough table, and you will, it is unlikely to lift. I have a small enough table that I dont have to have the slides underneath, but it would provide more even support for a bigger table.
I cant say enough about the torsion boxes. My first router, the flexomatic 2000, had a 36" long X 14" wide MDF table made from 1 piece of 3/4" MDF and it flexed EASILY. I can stand on this and cant see ANY flex at all.
By the way, the torsion boxes are filled with ground up rubber to add mass and absorb some vibes.
The pipe you suggested should be fine if it is rigid and hard enough not to dent under the pressure of the bearings. You will need to support it over the lengths you are talking about. My concept for the X axis with a pipe on top and bottom (not my concept, I borrowed it from somewhere else on this forum, just my execution of someone else's concept) pinched by the bearings on the carriage, works great. There is no flex at all, and it was simple to build. I just got the wood cut at Home Depot on their panel saw when I bought it. If you are only doing light cutting, this will be more than rigid enough, no need for metal I would think.
I am not up on the Cam followers concept, so I cant comment on that, sorry. Honestly, if I had another hundred and fifty bucks to throw at this thing, I would use DriLine (sp?) linear slides. Really, the pipe and bearings can be a pain but it is cheap.
I hope I touched on all your questions, please feel free to throw more at me.
What are your foam plugs going to be used for?

Thanks for the compliments VacPress. I am super happy with this one, now to see if it will do everything I want it to.....
co

johntbyrne
06-01-2004, 06:05 PM
Of course I'm interested in how the rubber worked out. May be no way of knowing improvement unless you built one without rubber but what do ya think now that you have it up and running?

Cheers
John

Hobbiest
06-01-2004, 08:20 PM
Gary...I would be worried about the clothes pipe denting along its length where the bearings ride. I is usually pretty thin wall stuff.

Cold Fusion
06-01-2004, 08:36 PM
The insides could be filled with some sort of concrete or resin?

yukonho
06-01-2004, 09:19 PM
Well, JTB, you are right, I cant compare it to the same machine without the rubber in it. I could take the rubber out of the table, but not out of the X axis torsion box.
Here is what I CAN say though.
I did some cuts today. HOLY CRAP! this thing kicks butt! The Z axis is a bit weak still, I have not got a solid spindle mount, the one on there is made from Delrin, and there is some obvious flex. That being said, this thing rocks compared to my other router. NO chatter at all in any cut that I have done yet, and I can take much deeper and faster cuts than before, no worries!
I believe that the added mass of the rubber is having some effect. Maybe not drastic effect, but something.
Yes, the design is far better than the first one, and I am using a much heavier spindle now, a 5A rotozip instead of a Dremel tool, so it is impossible to even compare the two on even ground.
Cant wait to get the spindle mounted better and get the lid on it.

I guess one could fill the cavities with Concrete or Resin, If you were using the machine to make heavier cuts then sure. But I am sure that this will be able to cut Al at reasonable feeds. (I probably wont, due to the mess factor and the oil/MDF combo not being such a good idea)
I could not be happier with this machine, I love it!
co

johntbyrne
06-02-2004, 11:31 AM
Any chance for a short movie of her in action? BTW, nice work! Looking at August to complete my house and then I'm going to build by router. I'm watching your progress with interest and may copy much of your design if you don't object.

As always Cheers
John

yukonho
06-03-2004, 08:37 AM
I keep going to take pictures, but everytime I think of it, my girlfriend has the camera at work.
Copy away! If you can replace the pipe and bearings with "real" slides, you will be a cut above this one.
Have I said how much I love this machine?? Really, probably the coolest thing I have ever made, and I have made a bunch of stuff.
co

javamatte
06-03-2004, 10:59 AM
Yukonho, I've got a couple of questions :)

I am "emulating" (read: copying) your design for a similar sized machine. I've looked around, and this seems to me to be the most mechanically sound machine that I could build given the tools at hand. One thing I haven't seen, though, is how you are driving your x-axis (gantry). In one of the earlier CAD drawings, you had what looked like holes for the acme rod near the bottom-rear corner of the gantry slide.

1) Is this where you ended up driving it?

2) Does it have any binding problems being driven off center (I don't see any way it could be driven from the center given that the fixed torsion box occupies that space)?

3) Just how "snug" are the bearings on the gantry? It seems to me that the whole gantry slide (box?) would be able to "rotate" (rock toward the front or back) around the torsion box and pipes? Does the box keep things that inflexible?

(that last one was cheating! :) I crammed about 3 questions in there...sorry!)

By the way, congrats on making a GREAT machine. It looks like this design should be a much more stable MDF machine than any of the moving gantry MDF ones I have looked at. BTW, my father (a wood worker of many years) laughed when I told him about the "new" ideas I had come across for a torsion box. He the proceeded to show me about 5 boxes used as tabletops or in various structural members around his shop. Ahh the joys of interdisciplinary learning! Looks like we all still have things to learn from one another...

-Matt

yukonho
06-03-2004, 12:10 PM
IT works!
The enclosure is done and it really makes a huge difference! Noises are now down to a point where you can stand beside it and talk to someone in a normal voice. Going to hinge the lid now wooheoooeee

java.
I ended up running the x axis motor on the bottom/back of the torsion box, pretty much where I drew it. I think it is probably better than having it in the middle because the load is at the tip of the bit, and this puts the lead screw about half way between the bit and the top of the slide.
No binding issues at all.
Adjusting the bearings well is a challenge. I think the best way would be to make the Z carriage from aluminum and slot the bolt holes so it could be adjusted. It is just not possible with MDF.
The bearings are pretty snug. I used some hard rubber under the angle that holds the bearings and it keeps the pressure on pretty good, but not perfect. Linear slides are the way to go. I will think about some driline or IGES slides in the future.
The torsion box keeps those rods damn stiff. There is no flex at all, I mean 0, of course there is probably a bit, but none that I can measure. Maybe a bit in the carriage though, but not too much.
Good luck with your machine and thanks for the compliments.
co

yukonho
06-03-2004, 09:51 PM
pictures

yukonho
06-03-2004, 09:52 PM
nudder

Mr.Chips
06-08-2004, 11:24 PM
Good job Yokonho, its a well thought out machine with all the bases covered.
Mine is on hold for now. We just sold our house in Austin Texas and will be moving to Tucson AZ the end of this month, so hopefully by August I can get back at mine.

Eager to see the video.

Keep up the good work.
Hager

yukonho
06-08-2004, 11:57 PM
Thanks.
Good luck with the move.
One week and about 30 hours of running, no problems yet. I love the enclosure. I can sit beside it with it running and carry on a conversation without raising my voice, and the dust all stays inside.
co

buscht
06-09-2004, 09:09 AM
yukonho,
You have made one sweet machine. I might just have to modify my router to utilize an enclosure just like yours. I can only run it now when my wife is gone, the noise gives her a headache.

Great job.
T

yukonho
06-10-2004, 12:11 AM
Thanks.
I live in an apartment and actually run this router for hours each day! No louder than a vacuum cleaner!
Some designs lend themselves to an enclosure better than others, and, of course, the smaller the better.
Cut some heavier G-10 today for the first time. My old machine would scream like crazy with the bit chatter and resonance in the machine. This one made no more noise when cutting than when not!
Stoked.
Still!
co

robgrz
06-10-2004, 01:09 AM
Is that G10 circuit board? Are you doing some microwave work? I'd be interested in what kind of detail you're able to hold for that type of work.

Robert

turmite
06-10-2004, 02:03 AM
yukonho nice machine and enclosure. I have been following the build of this machine and I can almost see the northern lights in your eyes!:D

Mike

yukonho
06-10-2004, 11:48 PM
Thanks turmite.
mmm northern lights .....
robgrz,
No microwave work here. The G-10 I was cutting was parts for R/C micro helicopters. I designed this machine around the needs for my business.
Small, Rigid, Quiet, Accurate, Fast, (Funky) in no particular order, I needed all these features.
I have not done any real measurements yet because the machine is not finished. I am going to have an aluminum spindle mount made up, and I just decided this second that I am going to ditch the pipe and bearings for some "real" slides. This machine is worth upgrading, my first one was worth..uh.. replacing.
The repeatability, accuracy and precision definitely meet my needs, my parts have never looked better.
co

turmite
06-11-2004, 02:01 AM
yukonho I couldn't spell "aroura boreallis"! I still can't!:D I need to build an enclosure for my machine but the size kinda scares me. My cnc would need a enclosure that measures 9X13X3! That's feet too. Can you imagine trying to lift the lid on that puppy?

Mike

yukonho
06-12-2004, 12:07 PM
turmite, that size of an enclosure is typically called a garage! And it can be equipped with an automatic door opener too! Sounds like you have a new project.....
Aurora Borealis
Aurora Australis is the same phenomenon in the southern hemisphere.
Never seen the australis, but have been lucky enough to witness Aurora Borealis that still makes my spine tingle when I think about it.
Truly among the most memorable experiences of my life!
robgrz, I just drilled a bunch of circuit boards. Happy to report that the holes were all bang on. Again, I have not measured the accuracy or precision, but to guess I would say positioning within .007" will be better no doubt when I go with linear slides and better anti backlash nuts.
co

mvaughn
12-20-2004, 02:37 AM
Yukonho,

I'm curious to know how your machine is holding up. Do you have any know comments about your design, any regrets?

I really like the design and would like to build something similar for my second machine; if I ever finish my first...

Do you plan on releasing any plans or drawings?

yukonho
01-16-2005, 12:33 AM
I plan on updating the machine soon. Going to make some better nuts and going to scrap the gas pipe and rollerblade bearings and maybe try IGUS slides or something else.....
I would love to do plans up, and I am in fact playing with CAD these days to update the design a bit, hopefully I can dedicate some real time to it over the next month.

As far as holding up, I must say that this thing is the bomb! I run it nearly daily, and have only a couple things that I need to take care of. The lead nuts I made are sloppy, so new ones are on order. I used 3/8-12 Acme, and it is difficult to get nuts for this pitch, so I would probably go with 1/2-10 next time. The thrust bearings need to be doctored up a bit as they are not well designed (by me :) ) My rotozip spindle exploded (literally, the fan blew apart!) so I bought a porter cable trim router. WAY better in every way except that it only accepts 1/4" shank bits.
This design is so rigid, the torsion box concept is the heart of the machine and really works better than any other concept I have tried. I couldn't be happier with it, honestly.
I was thinking of some kind of door that more rotates into place instead of swinging up like this one does, but that would be a lot of design work, and opening and closing the door is no big issue really. The door is not heavy, and it is very rigid, doesn't wobble at all. Mainly I run two cycles on the machine, one is 1:30 and the other is 0:26 seconds, and opening and closing the door that often isn't a big deal, so if you have longer cycles, it wont be an issue at all. The windows provide super clear view of what is going on inside. I may add internal lights in the future too.

colin

yukonho
01-19-2005, 06:57 PM
I just received word from IGUS. It looks like their DriLin slides will work well on my machine, so off to the drawing board I go.
I plan to do a full retrofit and lose the steel pipe and ball bearings that I now have (kinda wobbly) as well as some better lead nuts.
co

Mr.Chips
01-19-2005, 07:31 PM
That sounds like a good move. Can't say you didn't give the gas pipe and ball bearings a fair try.

Keep us posted with drawings and pictures.

Regards

Hager

Jay C
01-21-2005, 12:16 PM
Guys, I talked Clin into making a video of the beast in action. He sent me a 2minute 27MB quicktime file :eek: I converted it to a windows media file (3.5MB) and zipped and uploaded it here (http://www.rchomepage.com/~jcouture/). If CNCzone would host it, that might be better as rchomepage might change their mind ;)

Jay

Jay C
02-20-2005, 02:58 PM
Guys, does te video download for you? I haven't seen any comments on it since I've posted it and I think it's a great demo of Colin machine :conf:

Anyone reading this???

Jay

gmfoster
02-20-2005, 10:22 PM
Guys, does te video download for you? I haven't seen any comments on it since I've posted it and I think it's a great demo of Colin machine :conf:

Anyone reading this???

Jay

I watched it back when you posted it. It a pretty clean looking machine...

Garry

edbo68
02-20-2005, 11:35 PM
Yes!The video downloaded fine.

Love the Machine! Great Job!!!!

Jay C
02-21-2005, 10:57 AM
Just wanted to make sure that the vid was working and that Colin got the props he deserves ... thanks guys.

Jay

JavaDog
02-21-2005, 12:14 PM
Just wanted to make sure that the vid was working and that Colin got the props he deserves ... thanks guys.

Jay

Very cool video, and nice machine too!
Can never get enough of those CNC videos!!

Mr.Chips
03-02-2005, 10:55 PM
Yokonho,
Hows the progress, havent seen anything lately.

I see Ger21's building a CNC using the torsion box system. Being an old wood worker, I like the feel of this type.

Hope to see more of your work soon.

Hager

lurch
03-03-2005, 02:08 AM
Great machine! I love the design! Do you have any plans or drawings you would like to share for those of us who would like to emulate(copy) your design??

Tell Colin, great video, I watched four or five times with a big grin on my face!!

Beutiful setup, congratulations!!!

yukonho
03-09-2005, 02:03 PM
I am working on an update to the machine.
I have nearly got it completely laid out to be CNC cut, but I am short on time these days.
I am considering making it compatible with both Steel rod and bearings and IGUS linear slides (which work very well in this design) but it is a bunch of work, and I think there would only be about $80 dollars difference in price between the two systems. Currently it is designed for just the IGUS slides.
Any thoughts?
colin

lurch
04-28-2005, 05:22 AM
How goes the refit??? Drawings finalized with the slides? I'd love to have a look see. I've nearly got my 1st router up and running, but it is too big for the room I have to use it. A smaller more, finished looking, quieter unit is in order. Again, a great design, well worth imitating!!

yukonho
04-29-2005, 02:09 AM
Hi Lurch.
Just got back on this actually, life got in the way......
Drawings very very nearly finalised, slides on order. Once the slides arrive I will check actual measurements to my drawings, and off to the CNC router they go. So, with any luck, I will have everything ready to start assembling within 3 weeks.
The major part of the redesign was making everything key into place. This will make it easier to build true, and hopefull go together quicker.
I will post pictures once everything starts to roll.
Thanks for your interest, I still pat myself on the back for this design, still very pleased with it.
colin

lurch
05-12-2005, 02:56 AM
What is the distance between your y axis rods? I'm trying to work this out, see attached bmp. I've got a distance of 5.5 inches between rods on the y axis.....

ynneb
05-31-2005, 06:52 PM
I cant believe how I can completely miss some threads.
Thats a fantastic machine.
Great video too.

I love the way its is enclosed. That must make a big difference to the noise factor.

yukonho
06-01-2005, 05:08 PM
Noise and dust are greatly reduced, it is far quieter than my shop vac, you can talk at a normal level easily with the machine running, no hearing protection required. Dust is also non existent outside of the enclosure. The design is also particularly rigid.
V2.0 is almost ready to go to the CNC shop (and V2.1 is hot on its heels!)
co
thanks for the kudos

mvaughn
06-01-2005, 07:19 PM
Yukonho,

When you get your drawings finalized will you post them in a new build thread?

yukonho
06-01-2005, 09:47 PM
I found out today that I have a new home to move into in July. I will have a real shop! It may take some time to organise it like I want though. The point is I will actually have the space to do a proper build and document it.
The plans are not plans as such, they are toolpath type drawings ready to be programmed for a CNC router to cut it out. I have considered offering kits of the wood parts, depending on what the CNC shop cost ends up being. It is my old workplace, and we have a good rapport, so maybe I will get a preferential price, but I am not counting on it.
co

hsgreer
10-05-2005, 10:58 PM
Yukonho,

I tried sending a PM, but your mailbox is full. I'm a newby here and I've been reading the thead about your torsion box design. I want to build one. Do you have any plans I can purchase along with any precut parts?

Thanks,

Steve

johnathan
03-28-2007, 11:07 AM
good machine