Machsupport Forum
General CNC Chat => Show"N"Tell ( Your Machines) => Topic started by: zonian1903 on December 27, 2010, 09:54:46 PM
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Hello everyone!
Here are some pictures of a lathe we use to turn railway wheels that I converted to CNC using Mach3. So far, the servos, drive and control are installed and work very well. I've done a few tests with Mach3 and everything has blown away my expectations. I also found out the hard way why one should install the limit switches before you go playing and testing stuff... This week I am going to start putting the electronics in their proper enclosures and knocking out all the details necessary to get it working (ball screw covers etc.)
Specs---
Year: ???
Max turning diameter to ways: 60"
Max length between centers: 8 Feet
Spindle HP: 25
Spindle R.P.M.: Approx 20 (Low Gear) and 160 (High Gear)
I'd be happy to answer any questions about the setup.
Enjoy!
Frank
(http://lh3.ggpht.com/_pctjkEwJ5BE/TRlOuuXb7jI/AAAAAAAAAA8/qD15pYSLjCI/s800/front.JPG)
(http://lh4.ggpht.com/_pctjkEwJ5BE/TRlOyEb-8GI/AAAAAAAAABc/o6hG4s6uI4M/s800/side_1.JPG)
(http://lh3.ggpht.com/_pctjkEwJ5BE/TRlOyZ2w_WI/AAAAAAAAABg/7EXjwOLClwo/s800/side_2.JPG)
(http://lh3.ggpht.com/_pctjkEwJ5BE/TRlOy5LumjI/AAAAAAAAABk/RDFqtWmhOuc/s512/slide_6.JPG)
(http://lh4.ggpht.com/_pctjkEwJ5BE/TRlOvRwFtTI/AAAAAAAAABE/AVI9q48GWfM/s800/slide_5.JPG)
(http://lh4.ggpht.com/_pctjkEwJ5BE/TRlOzGQqdhI/AAAAAAAAABo/MYIXmf3d0g0/s800/100_0020.JPG)
(http://lh4.ggpht.com/_pctjkEwJ5BE/TRlOza11K4I/AAAAAAAAABs/GwhWqmcH4hM/s800/test_cut.JPG)
(http://lh3.ggpht.com/_pctjkEwJ5BE/TRlOv-X2COI/AAAAAAAAABI/bRlru1w4OJ4/s800/slide_4.JPG)
(http://lh3.ggpht.com/_pctjkEwJ5BE/TRlOwNBR6mI/AAAAAAAAABM/HmRuycUGLPU/s800/slide_3.JPG)
(http://lh6.ggpht.com/_pctjkEwJ5BE/TRlOw5Xxd0I/AAAAAAAAABQ/UZjg0o6F0RQ/s800/slide_2.JPG)
(http://lh3.ggpht.com/_pctjkEwJ5BE/TRlOxDllWCI/AAAAAAAAABU/3WELGF7okmI/s800/slide_1.JPG)
(http://lh3.ggpht.com/_pctjkEwJ5BE/TRlOxjgH3YI/AAAAAAAAABY/b5ImNY6H1Pg/s512/dist_panel.JPG)
(http://lh6.ggpht.com/_pctjkEwJ5BE/TRlOzi7mwyI/AAAAAAAAABw/_M2R6-kOpq0/s800/drivers.JPG)
And this is what happens when you start playing with stuff before you install the limit switches. Luckily, the ballscrew sprung right back to shape with 0 runout, I did have to re-do the mounts for the servo and gearbox. ;D
(http://lh5.ggpht.com/_pctjkEwJ5BE/TRlO0DePuwI/AAAAAAAAAB0/d8o3XVQr3Cw/s800/crash_1.JPG)
(http://lh4.ggpht.com/_pctjkEwJ5BE/TRlO0fo9DhI/AAAAAAAAAB4/BUz18K8V7L4/s800/crash_2.JPG)
(http://lh4.ggpht.com/_pctjkEwJ5BE/TRlO0nzELLI/AAAAAAAAAB8/Rt3erd2iFIE/s800/crash_3.JPG)
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That is really awesome to see Frank!
Thanks for the great photos and explination of what it's used for. Very interesting. :)
Kerry Harrison
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Wow, now aint that somethin! The original purchaser would likely be amazed at an electric motor hooked to it for power, much less a machine that makes cuts all on its own. Thanks for sharing it with us!
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That is some machine.
Thanks for sharing the pictures with us Frank - please update this thread with your future progress.
Tweakie.
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Looks great :)
What size servos are they and is that a gearbox between servos and pulley?
On a side note I have never understood why old lathes (American especially) have such small wings on the saddle compared to the centre height, I would imagine it would make it difficult to take a decent cut without chatter.
Hood
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Thanks!
I believe the machine is from the early 1940's, it didn't have a motor when we recieved it, but I am pretty sure it was electric. The machine came to us from a shipyard (the original owner) and was exclusively used for straightening prop shafts and had been replaced by another machine many years before. Other than a little clean-up it was ready ready for use... its amazing how excellent old fabrication is.
The servos are Panasonic 750W (1 H.P.) 3P 230V units with matching drivers. I am using Parker 50:1 gear boxes on both axis. Because most of the cuts on this machine are slow (20 R.P.M. low gear and about 164 on high gear) and deep (we regularly did 15mm cuts manually before the conversion), we decided to add the 50:1 gearboxes to increase the feed torque at the low feed rates required (approx. 15mm/min low gear and up to 40mm/min in high gear). So far it looks like that was a good idea, the only draw back is that my max shuttle speed is roughly 25 cm/min on X and 50 cm/min on Z. But even at that speeds its WORLDS better than the 5 minutes it would take to shuttle the saddle BY-HAND from one end to the other! ;D
The ballscrews are .75" diam/5mm pitch on X and 2.5" diam/10mm pitch on Y.
The timing belt and pulleys were a last minute thing, my father was concerned that having the X axis servo and gear box straight out from the saddle would risk it being ripped out by a careless forklift operator, falling part etc.
Hood, you are certainly right about the chatter being a pain, but its not from the saddle flexing, its from the play on the ways when the X axis out past the Z ways, the way guides need to be very well adjusted for play. It doesn't happen very often, but when you start to see chatter (see pic) its almost always because the X or Z way guide needs to be tightened. We also fabbed the tool post and holder ourselves because the original one wasn't sturdy enough for the wheels (another thing that caused chatter). I'll post a pic of the original tool post in the afternoon.
Frank
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Sounds like you should have plenty torque there :) 50:1 will be giving you 100 or so Nm I would imagine.
Hood
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I'm sure Sam(moderator) reply only because you have include a picture with a bottle of WD-40 ;D ;D
Could not resist.
I love this picture
Jeff ;)
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Darn right. We hillbillies use the stuff as cologne, before a night out on the town.
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Sam,
Did you say, "Hill Billie"? If so "wer u from", I am just a little north of "Knox-vagus" (knoxville, tn).
scott
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Frank,
Looking at the cross slide and position of the tool post was the lathe originally operated from the back, so to speak ?
Tweakie.
btw. Just found Sam's Christmas present - thanks Sam.
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Nice little lathe ;) Amazing how well it's preserved. It's 70 years old and looks better than some 10 years old machines I've seen.
0.75" diameter ball screws..? Sounds to small for a lathe that will cut 15mm per pass. Would expect twice that. At least for the Z.
Dan
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What a BEAST !!! Cool old IRON, I love it.
JH
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That's way to fancy a bottle, Tweakie. We gotta get a 'lil bit of dirt and grime on us when we apply it. Scott, I live close to Athens. I missed you guys at the Athens diner get-together a few years back. We've actually had this discussion when we spoke about Unitrac a couple years back. I'm thinking you done some machine work for their railroad equipment, if memory serves. Retrofit maybe?
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Sam WD is good fufu, but it make a better mouth wash ;D
Tweaky -- You know, I 've been around this machine for over 15 years and I never thought about that! But you are right, the tool post is on the "wrong" side DOH...wait, maybe its from the U.K.! :o
Dan -- The original ACME screw on the X was also .75" and according to spec its within spec as its pulling from the axis inwards. Remember that the heavy feed is actually being performed by the Z as the tool cuts heavy across the profile at the prescribed depth... shooting your tool into (as opposed to across) the profile 15mm at a time would make for a bad day to say the least. Take a look at the Z screw again its at 2.5" diam its actually 3.33 times larger than the X ;D
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Ah... OK. That makes sense. I was bothered with the Z axis as I said. Being 2.5" diameter, I see no problem ;) Somehow I missed you saying the Z was 2.5" and it was only the X with the 0.75".
Dan
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Hey Sam,
Oh, ok, I am sorry, my memory and me, is old..... Yes, I did the Screen set, and Brians for the Uni-track machine, but I did it for Derrik "Hillbillie" Ashburn. He did ALL the rest of that machine, and really only needed me, just cause he was under a time constaint and I could crank out a screen set/brain faster. He did a Superb job, on that machine. It had Two Z axis Heads and Two Y axis (one for each head), I had to make some custom controls so that you could slave and unslave Y's/Z's, plus it had a W axis as well. In total it had all 6 axis being used. If memory served since it was a MASSIVE planner mill, he had to use a 30 hp. Baldor motor for the X axis. The machine cut Switch Track rails for the railroad, so the overall tolorance wasnt that critical in the X, I think it was within the envolope of the normal gearing "slop" of the machine.
At any rate, I was wondering, since you live so close to me, if I could come and see that lathe!! Could you give me a call on the phone if it is a do-able thing?
865 four two six 9728.
I would LOVE to find some old iron like that, that is even close to that good of shape!!
scott
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:) This is not my post about the lathe. Its Franks lathe (zonian1903). His location is not set in his profile, but I doubt he's close to us. Bummer. I'd like to see it turning some parts.
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I'm working over-seas in Panama, however I'd be more than happy to have y'all over for a beer or two or three if you're ever in this neck of the woods. Today, we've been putting the finishes on the machine: covers, closets, pans etc. I think that by Tuesday I should be ready to turn some wheels after I do some test runs. I'll be certain to post more pictures and some videos once I do. Question: Can I embed a youtube video on the forum? If so, how?
Frank
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Hello everyone!
Last night I did the first tests of the lathe using lazyturn and machturn. I gotto tell ya lazycam is much more functional than I expected. The video was done at night, so its a little dark and grainy (sorry about that) but I couldn't wait till today to test it. ;D In the video, a 50mm radius bar stock has already been brought down to 47mm in one pass and the video starts at the next pass which is 3mm deep with a 15mm feed rate at 164 spindle rpm. The tool is a 1" high speed steel blank I had laying around (I didn't want to test on $100.00 inserts ;D). I did a quick and dirty groover grind on it and slapped it on with a little angle to hide the face and cut with the leading corner as if it were the tip on a bit. There was a little chatter, but I attribute it mostly to the small tool (we usually use 2x2 and 3x3 tooling) and that my grinding was piss poor. I haven't installed the coolant system yet so I just cooled down the work with a little 140w when the chips looked like they were coming out too hot. Even though the tooling wasn't even close to being the right one for that type of cut and had no coolant, I did 2 more passes and pulled it to see and it was still pretty sharp. I was guessing it would last one or two passes at most.
http://www.youtube.com/v/D3JaiqHLLeE?fs=1&hl=en_US&rel=0
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There is an enormous amount of satisfaction when something works as anticipated and it looks like you are well on your way to completing this machine now.
Brilliant work (and video).
Tweakie.