Second machine design process

[Mr.Chips]

Think you may be refering to his other thread, I gave the same comment on both threads.
Hager

[yukonho]

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
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]

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]

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]

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]

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...=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]

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]

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]

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]

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]

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]

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]

cool and COOL

[yukonho]

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]

I'd like to see a picture of you IGUS rail system, looks pretty nice from their website.

[yukonho]

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]

barkster, I am making my first cnc router with igus rails. See http://www.cnczone.com/forums/showth...&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]

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]

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]

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