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View Full Version : Time to wade in ready or not.



fair451
06-29-2004, 03:09 PM
As mentioned in another thread by someone else " I have been lurking in the background" like him for several months now trying to put it all together. While I have learned much I am far from getting it all straight. Especially when it comes to ending up with g-code for what ever I may want to do. Thats been really frustrating. I'm sure I will get it at some point and as time allows for me to work on it. I have successfully written simple straight line and circle code as learned from the example of others. So I know I can at least get some work done on my machine till I figure out to get sophisticated code.
Here is my machine that I had a hand in building but the skilled aspects of it were done by a retired with machine shop engineer/machinest. I brought all the elements together and he made it happen based on the parts I brought in. The machine cutting lengths are designed around the THK BLK 1616D ballscrews I have. Which were just under 24".
This the link to the large photo...
http://home.att.net/~fair451/cnc/c2.jpg

Now that I have waded in I look forward to continuing to read and learn, plus for once I will free to ask the so very many questions I have.

Thanks,
Mike

Patrick2by4
06-29-2004, 04:48 PM
nice looking machine mike, I see you went with stepper motors. do you have any pictures of the electronics?
I'm in the process of acquiring all the electrical components myself. I'm also building a machine presently and I hope it turns out as nice as yours.
http://www.cnczone.com/forums/showthread.php?s=&threadid=4752

fair451
06-29-2004, 06:46 PM
Thanks for the complement Patrick. Nice of you to say. A lot of effort has gone into it to get us this far. Plus I see you are the one I found to quote. :D
Since I am new at posting I can only hope the image shows up here as it should. That is if attachments automatically show themselves. Not sure all that works just yet.

This is a picture of the drives and power supplies a few days before I completed that task.
Thanks,
Mike

arvidb
06-30-2004, 01:12 PM
Mike, very professional looking machine!

Have you had a chance to measure its accuracy? Have you tried to mill aluminum? How much did the parts (mechanical and electrical and everything else) cost you?

Arvid

fair451
07-01-2004, 11:18 AM
Arvid,

Glad you like the machines appearance. Nice feedback to have.
Yesterday the machines accuracy was checked with a dial indicator. At its worst point the measurement was .003"

Have not cut anything but MDF so far and that was just a few test cuts.

Machining and layout costs were $600.00. Aluminum for the frame came in at about $120.00. Parts were reasonable as they are the very ones I buy to resell.

For project log I in the process of trying to come up with a table top. I have made one already out of .75" MDF but have found I need to make it over again.

Priced mic 6 .50' x 22.5" x 30" @ $250.00.

Mike

Dan S
07-04-2004, 03:25 AM
Mike

thats a great looking machine. I seem to rember wining my y axis rails from you :D

where did you get your aluminum from? I have been looking all over the net, and saving links for when it comes time to buy mine.
and from what i have seen the aluminum is going to be the most expensize part of the frame.

fair451
07-06-2004, 01:42 AM
Dan,
Do recall selling you some rails. Hope they are working out for you! See you shared photos of those most excellent rails.
:D Your doing so probably helped me out a bunch. Thank you!!!
For aluminum frame materials I went local dealer through one of the machine shops I do business with. Some of the material I already had. For the first machine anyway. No sense pitching the good stuff I'll only have to hunt up later. Coldfusion posted a note where a ebay seller has some stock for sale. I was thinking of getting some stuff from them but got no return answer to a note I sent. Probably a glitch. If you have a scrap yard local to you go browse what they may have. Always worth a peak on a regular basis. Did I mention that is my best advice out of any advice I might have to offer which ain't much? :rolleyes:

Mike

Dan S
07-06-2004, 03:34 AM
I have been watching eBay for aluminum but the prices seem to have a great range, and so does the quality of the aluminum.

Your rails are setting behind me as I type this. Good news it I'm moving out of my college apartment and into a nice quiet duplex with a garage to work in :D . Bad news is I have some other large house hold purchases I need to make before I can devote the extra discretionary cash to the cnc project :( . I need to hold my self back and not go crazy on eBay with the credit card :nono: .


If you get any shorter rails in the 12-18” range say SR20 or SR25 let me know, I’m looking for some larger longer rails for my z-axis, because I’m not happy with the ones I currently have :rolleyes: .

I understand the not having allot of advice when it comes to cnc, I’m in the same boat. Now if you have any physics or computational physics questions, those I can answer .:D

fair451
07-06-2004, 07:51 PM
Dan,
Best I can come to your rail needs is either 11" THK RSR20 or 25" SR20W. Either one comes in pairs and both are excellent.

For aluminum frame materials I had to shop the local outlets as I was not finding what I needed on the net or elsewhere.

Understand your issues. We just did a move and that has presented us with some challanges like yours. As for the credit card I am trying to stick with the rule that if I can not pay cash then I can't afford it. :D Its a good rule when I can put it into practice.

Mike

Cold Fusion
07-06-2004, 09:12 PM
Hey Mike, did you ever find that email containing the instructions for the stepper setup?

fair451
07-07-2004, 01:12 PM
Andrew,
I think this may be it. For Turbo cnc go to Set up machine - Motion set up. Then for a place to start change the defaults to...

1. Max Speed (Hz) 12000
2. Accel (Hz/s) 14000
3. Max Start Speed (Hz) 1500
4. Pulse Width 1

These values really settled my motors down. I have not fooled with these numbers yet to see what changes.

Mike

Dan S
07-07-2004, 01:26 PM
Mike

I sent you an e-mail, let me know if you don't get it.

fair451
07-11-2004, 01:22 PM
Andrew,
I did find the info and sent it. Did you get it and are you beyond those problems now?
Mike

Cold Fusion
07-11-2004, 02:55 PM
Actually I did. It turns out the drivers need a line between the ground on the 5v power supply and pin 25.

fair451
07-12-2004, 12:34 AM
Length has been added to the Z axis from a short 1.5" to 3.5" +/-.
We were really wasting the total travel of the KR33 being used to keep it at the short 1.5".
Heres a picture of where we are with it now. Lots of room to work.

fair451
07-12-2004, 12:41 AM
Detail of the new parts shown to the left and the old ones to the right. Only part used again was the single black horizontal motor attachment plate.

fair451
07-12-2004, 12:46 AM
Detail of the Y Axis bearings and ball screw before remounting the Z Axis.

fair451
07-12-2004, 01:31 AM
Detail of the KR33 and the Dewalt Laminate Trimmer. I picked the Dewalt for its narrow profile and nice round cast aluminum head just behind the collet. Easy to make a mount for. Plus the power potential to do serious cuts. Feed rate of F20 with .25" double fluted carbide bit doing a .25" depth cut seems to be no problem.

fair451
12-16-2004, 11:20 AM
Thought it was about time to post my progress. Have changed my table top and went with t-slotted backboard. Made my first table table top wrong. The daddo cuts I made on the bottom had inconsistant depths along the cut path and I thought this was why I was getting inconsistance cutting depths anytime I tried to cut something with the router. That didn't change when I started using the new table top. Concerning my thoughts on this type of material for a table top. I can see where it has promise but have found that it needs lots of support in order to remain truly flat. Because I have not installed that support yet I have found that I can only clamp down parallel with the t-slot. Any time I clamp down at a right angle to the t-slot the clamp lifts to board away from the machine frame. Just when I thought I was there I wasn't! The other part of the story is those inconsistant cut depths. The problem was/is driving me nuts.
So I have learned from others what I couldn't discover myself. I don't have enough power supply to work the system as I have it wired. Now to solve that if I can and still use the power supply I have. Go from parallel connection on the motors to series and back off the amp draw the drives where set at. Hope that works cause I am close to losing faith. ;-)

ViperTX
12-16-2004, 12:27 PM
fair451,
Looks like you did an excellent job...congratulations and thanks for sharing!

For the x-axis...did you use rails or the linear bearings?

fair451
12-16-2004, 03:27 PM
I think this is sort of funny once I discovered it, though I hate to disclose it world wide, but I had my x an y axis incorrect in my reference to them. Well that issue is squared away now. Where I refer to my y axis in this thread it is actually x. I have some sense of humor left so I can poke fun at myself about it. Both y and x are THK 20mm rails.

santiniuk
12-16-2004, 03:52 PM
Great looking machine !

ViperTX
12-16-2004, 04:21 PM
I think this is sort of funny once I discovered it, though I hate to disclose it world wide, but I had my x an y axis incorrect in my reference to them. Well that issue is squared away now. Where I refer to my y axis in this thread it is actually x. I have some sense of humor left so I can poke fun at myself about it. Both y and x are THK 20mm rails.

I saw your first pic of the y-axis and you also used linear rails.....I like the way you mounted them.

fair451
12-17-2004, 08:17 AM
Thanks for your recent feedback ViperTX & satiniuk! Mounting the rails went fast once assembly began. Just resized these pictures to post here.
Michael

ViperTX
12-17-2004, 11:14 AM
fair451....that's cool and slick looking...nice work!