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blfuller123
12-28-2006, 09:08 PM
I am really new to the cnc world but I have been lurking around here for a little while and now I'm in the process of building my first cnc router. I am basically copying the one in the CNC Robotics book by Geoff Williams but I am putting my spin on it. I want to be able to use this to cut mainly acrylic and some wood work.

The frame is going to be made of steel and is going to have a cutting area of around 40x30. I now have all of my rails and will be picking up the steel for the gantry in the next week or so. I am using THK rails and bearings for the X axis. I am using Thomson supported rails and bearings for the Y axis and I am using unsupported Thomsom rails and bearings for the Z axis. Basically what I could get good prices on. I still need to get the lead screws for the X and Y axis.

This is going to be kind of a slow project, but here is where I am now.

http://i17.tinypic.com/2nv9d9y.jpg

Mr.Chips
12-29-2006, 09:35 AM
A good start. Fully supported rails are always the best choice. Do you have any drawings of your machine?

Hager

blfuller123
12-29-2006, 10:40 AM
I do have drawings, but they are on good old fashon paper.

Mr.Chips
12-29-2006, 04:32 PM
I do have drawings, but they are on good old fashon paper.


I did that too.. Started with sketches then to full size drawings for some of the areas to insure it would work.

I made a moving table fixed gantry as I determined it would be more rigid. And I could build it with the woodworking tools I already had. Will use it to make my moving gantry machine.

Good luck.

blfuller123
12-29-2006, 05:20 PM
Have any of drawings of your machine?

JIMMY
12-30-2006, 09:40 PM
good start

blfuller123
01-03-2007, 08:53 PM
Well I picked up the steel for the gantry today and took some of it it is over to my buddies house for welding. Hopefully I will have it back in the next couple of days and I can get it put together. I also got the last piece of aluminum for the z axis. MAybe this weekend I will get something worth taking pictures of.

I think I have convinced myself to use one leadscrew under the cutting area on the X axis instead of two screws and steppers.

Mr.Chips
01-03-2007, 10:55 PM
In your photo I see acme thread and allthread.
Why use allthread if you have access to acme thread? Just wondering.

Hager

blfuller123
01-04-2007, 06:43 AM
Nope, no all thread in that picture.

Mr.Chips
01-04-2007, 11:43 AM
Nope, no all thread in that picture.

Thats good.

From the photo the smaller one looked like the threads were pretty sharp, vs flat on top.

Hager

blfuller123
01-04-2007, 09:43 PM
I got the two pieces of the gantry back from my buddy today and here they are. I will bolt the two pieces that go horizontally to these to make the Y axis.

http://i1.tinypic.com/49ab6f8.jpg

I got started on the Z axis tonight. I got the aluminum cut and started drilling it before the kids went to bed. I had to stop because the garage is just below my daughters room and the drill press was making alot of noise drilling the 1.25 inch holes. This is as far as I got. I should finish it up this weekend.

http://i14.tinypic.com/2yx1a50.jpg

Stile2
01-04-2007, 10:57 PM
Looking good so far!! Yeah RC!!

Fellow Reef Tank Guy following along!

Keith

Mr.Chips
01-05-2007, 12:18 AM
Keep at it.
I really like your photos they are so sharp and clear.
Hager

blfuller123
01-05-2007, 06:16 PM
Got a little more done today. Here is part of the z axis. Still need to get it drilled up for the lead screw.

http://i11.tinypic.com/2ezln9i.jpg

I drilled the holes for the y axis rails and test fitted everything. The next thing I am going to do is drill these pieces up and bolt everything together.

http://i16.tinypic.com/2vkdzl5.jpg

acontia
01-05-2007, 08:23 PM
thumps up for a fellow Reefing guy.

i bet u can cut out all the acrylic parts for your DIY build (skimmers, Ca reactor etc ) on a single work piece.

Mr.Chips
01-07-2007, 09:18 AM
Got a little more done today. Here is part of the z axis. Still need to get it drilled up for the lead screw.

I drilled the holes for the y axis rails and test fitted everything. The next thing I am going to do is drill these pieces up and bolt everything together.

http://i16.tinypic.com/2vkdzl5.jpg

You have really good seperation on your "Y" Axis it will support your "Z" Axis really well.
The two bottom tubes connecting your vertical pieces to your "X" axis seem kind of short, but not seeing a drawing or understanding how these work I could be completely of base.

Hager

blfuller123
01-07-2007, 02:15 PM
You might be right Hager. I went back looking at my book that has the router I am copying and sure enough, the feet on his gantry are 12 inches long and these are 8 inches. Do you think that will make that much difference? If so, I dont think it will be that big of a deal to change. I think I can put a piece of plate between the bearings and the gantry feet and extend the feet by a couple of inched on each side.

-Brett

Mr.Chips
01-07-2007, 06:40 PM
You might be right Hager. I went back looking at my book that has the router I am copying and sure enough, the feet on his gantry are 12 inches long and these are 8 inches. Do you think that will make that much difference? If so, I dont think it will be that big of a deal to change. I think I can put a piece of plate between the bearings and the gantry feet and extend the feet by a couple of inched on each side.

-Brett

I don't know for sure but I see quite a few machines with a longer base, but many of them are using skate bearings. You have a really sturdy box construction, so I would not suspect it would rack much when the router was cutting down. Plus you have excellent lineral bearings, to hold everything rigid.
At 8" it is probally fine. It was difficult to guess the length from the photo.
Hager

blfuller123
01-07-2007, 08:04 PM
Hopefully I dont get any racking. So far with just the top piece bolted up, everything is really sturdy. The bottom piece isnt drilled up yet, but hopefully that will be done soon.

blfuller123
01-12-2007, 07:24 PM
Here is the gantry all drilled up and painted awaiting installation of the rails.

http://i16.tinypic.com/2cp3uoy.jpg

blfuller123
01-12-2007, 11:08 PM
Here are a couple of pictures with the rails installed. I guess I was playing around more than anything, but I was also figuring out how to mount the Z axis. In the pictures, that is just some scrap acrylic with the paper still on that is between my Z axis and the bearings.

http://i11.tinypic.com/2sb8tw9.jpg

http://i13.tinypic.com/3yq8qa1.jpg

Mr.Chips
01-13-2007, 12:06 AM
Good looking Brett,
It is starting to take shape.

I started fooling around with Mach 3 today but just on the PC not connected to CNC yet.

Hager

Stile2
01-14-2007, 12:04 AM
Sweet looking so far! Congrats

blfuller123
01-18-2007, 09:36 PM
I got a good deal on some aluminum tubing yesterday. I am out of town, but hopefully when I get home, the tubing will be waiting to become my X axis.

blfuller123
01-22-2007, 01:32 PM
UPS showed up today and got the metal for the x axis. In the picture nothing is bolted together yet, but it is almost taking shape.

http://i13.tinypic.com/4hlc9z8.jpg

blfuller123
01-25-2007, 03:06 PM
I got the frame done for the X axis. I ended up standing the tubing up because it seemed to be a little more rigid this way. I butted the ends together and used some angle aluminum to bolt it together.

http://i12.tinypic.com/2vl7lhx.jpg



I made up a jig out of some scrap acrylic to mount the bearing trucks to the gantry feet.

http://i18.tinypic.com/4byy6wz.jpg

http://i12.tinypic.com/40bgxnn.jpg


Then I transferred the holes to the first gantry foot, drilled it up, then bolted the bearing trucks to the foot.

http://i11.tinypic.com/2eeeukw.jpg

I will bolt the first rail to the x axis frame and get the next rail parallel before I drill up the other foot on the gantry.

http://i10.tinypic.com/2upsql4.jpg

The wife is out of town for a couple of days and I am working between the babies naps so maybe I will get a little more progress done in the next couple of days.

-Brett

Mr.Chips
01-25-2007, 07:44 PM
Looks good Brett. Nice sharp photographs, super detail.

keep up the good work.
Hager

blfuller123
01-26-2007, 11:44 PM
Thanks for the kind words Hager.

I got the x axis rails squared and mounted and the bearing trucks mounted on the other foot. It turned out to be a little easier than I expected. I also started making my jig to mount the Z axis to the Y axis. I got it drilled up and test fitted on the top half. I still need to get the bottom bearings located and drilled up. Where you see the acrylic, it will eventually be aluminum. I dont have much scrap aluminum, but have a lot of acrylic.

http://i11.tinypic.com/2nqtqps.jpg

Here is a better picture of the Z axis.

http://i13.tinypic.com/4ddlf08.jpg

I need to get to work on getting the bearing mounts made for the lead screws.

Mr.Chips
01-27-2007, 01:50 AM
Hey Brett, it's starting to look like a real machine now. Nice separation on the Z axis mount, both horizontally and vertically. You have plenty of support there.

Isn’t it about time you sit it up on a bench or something, your back has got to be killing you.

Keep up the good work and pictures. Even if they are BIG He He.

Hager

blfuller123
01-27-2007, 03:20 PM
I should do something, its starting to get heavy.

Greolt
01-27-2007, 04:54 PM
Brett I am enjoying watching your machine come together. Looking good.:cheers:

I don't know if anyone else has sugested this but instead of "insert image" go to "Manage Attachments" and upload your pics that way.

This makes a thumbnail appear in your post which interested readers (like me) can click on to see the full size pic.

Makes it easier for readers to load your posts. :) Keep it up. Well done.

blfuller123
01-30-2007, 01:36 PM
Thanks Greolt, but I have never used the insert image function. I have just pasted the "IMG" file to the thread. Where is the Manage Attachments button?

I was looking around at electronics and have a question for someone. I am considering using a Xylotex three axis kit with the 497 oz motors. Does this seem sufficient? I will be using acme 1/2 10 thread for the lead screws. With this being my first machine, I would really like to get the electronics part as a kit if possible. If not, any other suggestions?

-Brett

Buzz9075
01-30-2007, 01:41 PM
You might want to review these threads:

Last pages of this one:
http://www.cnczone.com/forums/showthread.php?p=249911#post249911

http://www.cnczone.com/forums/showthread.php?p=249810#post249810

Greolt
01-30-2007, 04:25 PM
..... Where is the Manage Attachments button?
What I do is. :)

Make the image a jpeg. That is a good format to keep image file size small.

Make it a max of 1000 pixels across the largest side. Use your favourite imaging program to resize if needed.

Upload as an attachment.

Hope this helps. :wave:

.

Rance
01-30-2007, 05:55 PM
...Make it a max of 1000 pixels across the largest side. Use your favourite imaging program to resize if needed...


I wouldn't hurt to crop out some of the insignificant areas on the edges too. :) It would help to conserve some of the disk space on our sponsor's servers. :)

Nice work, keep up the posts.

blfuller123
01-30-2007, 09:13 PM
Just doing a bunch of reading, I am wondering if I should use 2 drive motors on the z axis? The gantry is pretty heavy and it doesnt have the router motor, lead screws, or the y and z steppers on it yet.

LeeWay
01-31-2007, 06:40 AM
Looking good.
I have a couple things to consider before you make the decision as to one or two screws.
So far, there is nothing wrong with the design you have, however it looks like it might dictate the need for two screws. You could easily run the screws through the feet on both sides.
A single screw would best be done under the center of the table IMHO. You have a lot of weight for your gantry and a single screw on one side will tend to want to rack.
I have a heavy gantry as well, but I used only one screw. I do however have something that I don't see on yours and that is adjustments for both in and out at all four corners of the gantry feet. I am using skate bearings and this lets me preload all the bearings to ride on my steel rails and thus I have no racking.

I actually thought you were going to slip the bottom feet around your rail. This would give you somewhere on the bottom of the machine to add a third cross member and more area to mount screws to underneath. As it is, your design should work fine, but I think you may need two screws for sure.
Keep up the great looking job.

RyanS
04-01-2007, 03:21 AM
Bumpin this back up. Looks sweet. Any new updates?

blfuller123
04-01-2007, 11:06 AM
Nothing new. I have been busy trying to sell the house and the wife gets mad when I make a mess in the garage. I am shooting for this summer.

guido_kp
04-03-2007, 11:23 AM
best of luck selling the house. maybe you can convince her that shes seeing it all wrong. its not a mess its creating, its going to be saving you money since you can diy most of the expensive reef trinkets and maybe sell a few to finance itself. :)

so what have you decided to do as far as single/dual screws? what about screw mounting? i've decided to graduate up to a metal based machine. i would like ballscrews but after i just dropped a grip on 3 axes worth of thk linear slides, ballscrews are kinda out of the question for now. i think my acme rod and dumpster ab nuts are gonna find a new home on this machine. im kinda thinking about using your design but want to keep it under the table/single screw.

blfuller123
04-05-2007, 08:01 PM
I am still going back and forth on the screws. I will probabaly end up going with two of them, if for nothing else, for the extra juice. Who knows, I might still end up using an under the table single screw.

Yea, she doesnt see things like I do.

-Brett

blfuller123
04-16-2007, 07:53 PM
Alright, I think I have the go ahead to get my electronics from the wife. I have decided to usa a 4 axis kit and use 2 screws on the x axis. I am looking at the Keling with the 495 oz motors. Any thoughts?

blfuller123
04-18-2007, 04:19 PM
Anyone???

guido_kp
04-19-2007, 05:37 PM
havent used them, brett. but it looks like a good deal. i like the fact that its three separate drivers. so if one axis grenades its just a matter of swapping the offender out versus my hobby cnc board - all the bad components would have to be unsoldered and new ones resoldered in. i hope that i dont have to do that ever but it is a possiblity. also, the bob usually protects the pc from getting voltage back into the parallel port, unlike an all-in-one board. the powersupply is the part that i would have questions about. 24v is probably not the max the drivers/motors can handle. i am running my hcnc at 36 volts 10 amps total. so i would think these guys could handle more which equates to more speed. i dunno, tho, i am no expert. also look at the torque charts for the motors. these bigger guys, i think they are more efficient at lower speeds, so keep that in mind when deciding on leadscrew tpi.

kris

blfuller123
04-20-2007, 05:08 PM
Thanks Kris. What pitch screws would work best using these?

blfuller123
04-30-2007, 08:04 PM
Finally!!! I got my electronics ordered today. I ordered the 4 axis kit from Keling with the 495 oz motors. I also ordered my acme thread since Enco has it on sale right now. That will give me something to do for a little while.

blfuller123
05-08-2007, 06:33 PM
I have a question for someone. The stepper drives are rated for 24-40 volts and the power supply I have is 24 volts. Will it make a difference is I use a 36 volt power supply?

blfuller123
05-12-2007, 06:58 AM
I went a head an ordered an additional 12 volt power supply so now I have a total of 36 volts supplying power to the motors. Here is a picture of everything wired up.

http://i7.tinypic.com/54j7hwi.jpg

blfuller123
05-27-2007, 08:37 AM
Spent a couple of afternoons at a friends house making these anti-backlash lead nuts. Got 4 made now. Just have the screws left to turn and make the bearing and motor mounts and it should be up and running.

http://i12.tinypic.com/6coodog.jpg


http://i15.tinypic.com/62x9cso.jpg


http://i14.tinypic.com/54boqki.jpg


http://i7.tinypic.com/68h360z.jpg

ger21
05-27-2007, 08:59 AM
I have a question for someone. The stepper drives are rated for 24-40 volts and the power supply I have is 24 volts. Will it make a difference is I use a 36 volt power supply?

Useable rpm is roughly proportional to voltage, so 36V should give you up to 50% more speed.

Oldmanandhistoy
05-29-2007, 01:43 PM
Hi,
Very nice job on the anti backlash nuts. Do you have any info on the springs you used or a link?

John

blfuller123
05-29-2007, 05:23 PM
Thanks John, we ended up using springs from a 4130 transmission. We cut the nut 2 inches to start with. Then the flange is half an inch wide. The remaining 1.5 inches was turned down to 1 inch in diamater. Then we cut a 4 degree taper .5 inches from the end down to .93 inch. That made the od of the nut 1 inch at the largest part and from the taper to the flange, it is .93 inch od. The other piece we turned down to fit the spring for the od and the bore is 1 inch with a matching taper. Does that make sense? No link, just played around with it until we found something that worked.

Oldmanandhistoy
05-29-2007, 07:26 PM
Thanks John, we ended up using springs from a 4130 transmission. We cut the nut 2 inches to start with. Then the flange is half an inch wide. The remaining 1.5 inches was turned down to 1 inch in diamater. Then we cut a 4 degree taper .5 inches from the end down to .93 inch. That made the od of the nut 1 inch at the largest part and from the taper to the flange, it is .93 inch od. The other piece we turned down to fit the spring for the od and the bore is 1 inch with a matching taper. Does that make sense? No link, just played around with it until we found something that worked.

Thanks for the detailed reply:)

I was just wondering if you had made any calculation to work out the spring pressure required based on max cutting forces. From your description I realise you are using the nut compression method so presume it was a case of adding/reducing pressure until you were happy with the drag of the nut. The last anti backlash nuts I made worked on the same principle but all I did was split a nut three quarters the way down its length and used an O ring to apply the pressure (original idea came from another member) it worked very well.

Another method I have used to good effect was to use two standard nuts; one against the other to remove backlash. Trouble with this method was that manual adjustment was needed as the nuts wore. I would think making a nut like this which was self adjusting would need to take the cutting forces into account. Too much force the nut would wear to quickly and add unnecessary drag; too little and the nut would not remove the backlash effectively. I would be interested to know which method is the most efficient as a self adjusting nut. I do know that using two nuts without self adjustment adds very little friction to the system which is beneficial if you are short on torque because of under power stepper motors.

Sorry for rambling on it just happened so I thought now I’ve typed it I might as well post it.:p

John

blfuller123
05-29-2007, 09:37 PM
It was no real calculations. Like you said, until they felt right. These are self adjusting in a sense. They should keep the same pressure at all times. If I ever think they need to be adjusted, I should be able to just make another sleeve, but make the bore taper smaller/larger accordingly. Wont know anything definately until my machine is finished.

I am going back and forth on redoing the gantry;maybe a little shorter and using all aluminum. I have done as much work as I can on the machine for now. My wife is having a c-section this week and we will be moving shortly after that so my plate is pretty full. Who knows, I might just try it as is (like I said, back and forth). I keep looking at other peoples machines and keep getting tons of ideas.

-Brett

blfuller123
08-16-2007, 10:23 PM
Well, we finally got moved and I got started on my machine again. I built a wood stand with wheels so I could move it around. I got the screws turned down this past weekend and I my lovejoy couplings came in today. I pretty much have the z axis complete just need to mount the motor. I got the mounts done on the y axis too. Here are a couple of pictures of my progress before the battery in the camera died. Any luck and I will have her up and cutting in a couple of weeks.

http://i11.tinypic.com/5xqg7ph.jpg



http://i16.tinypic.com/669r4ep.jpg

greenb_60097
08-16-2007, 11:46 PM
Hi,
cool build. I was just about to order exactly the same motor kit and I figured that the power supply would have to be upgraded eventially. How do you have these wired so the voltages are added? What is the amps of the 12v. Have you noticed a difference between 24-36v?

Keep it up its looking great. Ger and other may chime in here but I often see them recommend a 1/2-8 2start acme screw, since ballscrews are out of the budget for me at this point I was leaning this way, my hope is that the 1/2" twin x drive is stout enough. I was thinking about using a 3/4" 10 2start (the biggest that will fit my lathe but I'm having a hard time locating a source for them.

How did the other poster pick up on the reef tank hobby? There's another expensive hobby, I've seen some cool pics over on reef central.

Brian

blfuller123
08-17-2007, 06:21 AM
I think I have a total of about 15 amps available with the second powersupply. It was easy to add a second one. I just found a 12 volt powersupply and wired the two in series to give mt 36 volts. As far as making a difference, I am sure it has but I dont have anything to compare it against. I wired up all the electronics when I first got them, and then wired up the additional powerw supply, but the were not driving anything.

blfuller123
08-30-2007, 08:43 PM
I got the screws mounted up and the motors mounted. All I have left is to connect the leadnuts to the axis's and wire everything up. Here are a couple of pictures.

http://i3.tinypic.com/4ml51sx.jpg


http://i9.tinypic.com/6b9lowo.jpg

reeftoker75
08-30-2007, 08:49 PM
looking good