Messages

181

General Mach Discussion / Re: ATC for lathe

« on: September 08, 2007, 10:05:16 PM »

It has a tapered pin in the rear of the turret, driven by a large electric solenoid. The design of the pin is a copy of an italian turret that  a Clausing Clochester Storm lathe uses. One important detail is to have the software 'vibrate' the turret a very small amount to help the pin settle in it's home, this design uses a stepper motor, so I would forward/ reverse the pulses just as the pin goes in to lock it. I haven't built it yet, but have all the materials and hardware ready to do it, probably will happen in six months or so.
   DaveA.

182

General Mach Discussion / Re: ATC for lathe

« on: September 08, 2007, 09:09:47 PM »

I talked about this awhile ago here http://www.artsoftcontrols.com/forum/index.php?topic=304.0
   DaveA.

183

General Mach Discussion / Re: Losing track of the Z height - gouging table

« on: August 25, 2007, 01:51:19 PM »

Might be better to set your Z height above the workpiece before doing any testing, certainly when you have had known issues with problems, saves having mechanical damage done to your equipment. CNC work requires a certain level of confidence, that is, you having confidence with the machine and that it will, in fact, do EXACTLY as you programmed it to do. When that confidence is not there, you have to play the safety routine to protect the machine.
       Dave.

184

General Mach Discussion / Re: Z Axis Problem Need Help Badly

« on: August 21, 2007, 07:56:41 PM »

Sorry Brett, I should have refreshed before posting, you got there before I did!

185

General Mach Discussion / Re: Z Axis Problem Need Help Badly

« on: August 21, 2007, 07:54:17 PM »

Plunging into aluminum at close to 20 ipm is pretty fast, I try to plunge at half the speed I cut at, and for a non flood coolant machine you are working it, must be a pretty rigid machine. But, you now have half the thrust you had with a .1" pitch leadscrew, the ballscrew being .2" pitch, this is a large difference I'd say, and the source of your problem.
                           Dave.

186

General Mach Discussion / Re: I NEED SOME HELP // DOES ANYONE HAVE A ROUTER LIKE THIS?

« on: August 13, 2007, 12:55:33 PM »

It doesen't seem to round corners off very much. Interesting to watch it run over a complex contour, accelerates and decellerates but not jerky at all. You can change that in the setup but I have left it as it was sent. Control also has a "broken Point" feature, if you need to change a tool during a cut you can stop it and have it save where it was, jog away and change the tool, etset the length, and it will restart where it left off. Also will do multiple parts in an array, you tell it the X and Y spacings and how many parts in the grid. Hardest part of it is the converted chinese instruction manual...
                        DaveA.

187

General Mach Discussion / Re: I NEED SOME HELP // DOES ANYONE HAVE A ROUTER LIKE THIS?

« on: August 09, 2007, 11:02:46 PM »

I have a similar router, larger, more rigid model than that. I have the DSP controller and use it. It is a very nice control, very reliable, machine easily cuts at 800 in/min, rapids over 1200. Yes, there is no graphic display on the control, but if you are so inclined to need to see one, you can leave it plugged in to the USB on a PC and watch the thing on screen. I use my CAM for the graphic cut display normally. Storage is a huge 32 meg, I have ran files as large as 4.2 meg, this is a text file, remember, and I have run it non stop for over 100 hours without problems. Servo drives are 90 volt on mine, which is part of the reason it has good speed. I have never had a problem with CV. I imported mine directly from the factory in China. I can help with issues, questions if needed, let me know.

188

General Mach Discussion / Re: Lathe Threading With Backlash

« on: August 07, 2007, 09:59:18 PM »

True, and I do that if time permits it (often doesen't!) but the groove is no weaker than the thread that the same tool cut, only difference is that the thread is a helix so has one pitch of the thread higher than the root, but the root is still the stress riser anyway. Main point here is still, not a lot of major advantages to the CNC tool pullout as far as strength, but it is really cool and has a neat appearance.

189

General Mach Discussion / Re: Lathe Threading With Backlash

« on: August 06, 2007, 10:53:53 PM »

Whenever I manually cut a thread, screwcutting, or single point as it's called, I machine that grove you are talking about in before doing the thread itself, this is typical in this operation I believe, and doesen't weaken the stud as long as the groove is no deeper than the root of the thread. When cutting threads the easy way, with a CNC lathe, it does the tool retract as you are talking about here automatically, which is a cool feature, but really doesen't improve the thread in any way, or the strength of the stud. So, unless it has major drawbacks to the operation, I say don't worry about it too much. Another thing to look at is, what RPM are you running these threads at? For a pitch of, say, 24tpi I would turn the spindle at maybe 300 rpm, this is tied to the acceleration your machine is capable of, and not so much the diameter because you try to not work the tool too much in case of breaking it, quite common with screwcutting. Too high of an RPM and you leave the control no time to try to retract the X axis.
                                   DaveA.

190

General Mach Discussion / Re: Lathe Threading With Backlash

« on: August 04, 2007, 11:06:52 AM »

Wes, G76 doesen't work like that, it's a canned cycle with it's own retract, pull out distance, etc figured in. Problem here is the machine backlash, as are many of the problems reported on this forum. As Brett said, you need to enable backlash in Mach, but this is only for "reasonable" amounts of backlash, if you have a half turn on the X axis leadscrew, not much here will help you. Time to invest in a ballscrew probably.
     DaveA.