Messages

261

General Mach Discussion / Re: MACH3 MachTurn not picking up "Index" on mini lathe

« on: June 13, 2022, 12:31:55 PM »

By the way there is a very good support forum for CNCDrive (who make the UC100) here:

http://www.forum.cncdrive.com/index.php

262

General Mach Discussion / Re: MACH3 MachTurn not picking up "Index" on mini lathe

« on: June 13, 2022, 12:05:44 PM »

Well, I can confirm that the UC100 should see the index pulse because that is how the spindle speed is measured, and my Mach3 Turn instance does show the correct spindle speed!

Clearly the sensor is picking up the slot which is good.  (There is just one slot, right?)  However Mach3 isn't seeing it.  You have set the card for Open Collector output, does it have a pull-up?  You could select TTL output if it doesn't.  Try active high, as the effective pulse length can be short or long depending on how the pulse is interpreted.  For debounce, as I said you shouldn't really need it with an opto so set very low.

263

General Mach Discussion / Re: MACH3 MachTurn not picking up "Index" on mini lathe

« on: June 13, 2022, 01:40:39 AM »

When I upgraded my shop with a new PC I chose the UC100 for both lathe and mill (separate units).  I asked a lot of questions of CNCdrive including about UC100 threading support and got this reply.

"3.) The UC100 works with the UCCNC, Mach3 and Mach4. The UC100 does
> not support thread cutting with Mach4. It supports thread cutting with
> index sensor with Mach3 and it supports syncronous thread cutting with
> encoder feedback with the UCCNC."

I haven't yet tried threading but every other function operates and it certainly picks up the index pulse from the opto on my spindle as it correctly displays spindle speed.  Does yours display speed?  If not there is probably an issue with the pulse signal.   It could be that the polarity is set wrong or the debounce setting is wrong (too large).  If you have an opto sensor debounce shouldn't be needed.  Have you looked at the signal on the diagnostics screen to check you can see the state of the input change when you slowly rotate the spindle by hand?

264

General Mach Discussion / Re: Dial indicators show random amounts after retuning to start

« on: June 11, 2022, 06:54:21 AM »

Not that I have noticed.

265

General Mach Discussion / Re: Two problems with Mach 3 - may be related?

« on: June 09, 2022, 12:43:21 PM »

Maybe missing steps on rapid moves on the Y axis?  Try slowing down rapids.

The other one I have never seen but I have read that the saving as .mcc works.

266

General Mach Discussion / Re: Touch plate question

« on: June 07, 2022, 02:47:59 AM »

Surely it's obvious that it doesn't!  If you mean the angle of the surface relative to the spindle axis, you can determine this by doing multiple measurements at different x and y positions and doing some maths.

267

General Mach Discussion / Re: Dial indicators show random amounts after retuning to start

« on: June 05, 2022, 06:59:13 AM »

Me too,  but my lathe has an 8 tpi leadscrew so steps/unit is an approximation, it works out to 2015.748 steps/mm taking account of pulley ratio and microstepping.  Since Mach can only generate integer numbers of steps the Z axis at least often shows very small errors like you describe.  Cross-slide uses a metric ballscrew directly driven from the stepper so that one is 1280 steps/unit - but still one step is 0.00078125 mm and since again it can only do integer step numbers you can get small "zero" errors. 

Another factor comes in when homing - if I home the X axis and zero the m/c coords, it usually will "rehome" very accurately (I have a hard contact home switch).  But after it's switched off but then switched on again when I home the new home position is often very slightly different and I think this is because steppers lose their microstep sequence when powered off which introduces a small error.  It's not a problem but it does mean that for accurate working one has to re-home every time the machine is powered up.

268

General Mach Discussion / Re: Dial indicators show random amounts after retuning to start

« on: June 04, 2022, 02:59:20 PM »

Do you work in mm and are one or more of your feedscrews Imperial?

269

General Mach Discussion / Re: Limits

« on: June 03, 2022, 01:39:51 AM »

Hello Rab, welcome to the forum.  I guess you maybe like me of an age where printed explanations are more useful than videos so I second TPS' suggestion to get a copy of the manual.  It could be useful to carefully save the xml backup file of your machine (read the manual) and then go right through the Mach3 setup process to make sure all the settings are correct, and you will learn a lot in the process. If an existing gcode file like roadrunner works though that should indicate that the setup is OK.  Could you post some gcode from Carvco that doesn't work?  BTW, it is worth buying a licence even though the cost for a piece of software that isn't supported except through a user forum is a bit steep.

270

General Mach Discussion / Re: multiple depth cuts

« on: June 02, 2022, 01:24:24 PM »

Not a problem, just that the expertise probably isn't here.