Messages

1

General Mach Discussion / Re: Rotary Axis Blues

« on: May 12, 2010, 06:05:59 PM »

This testing was done using a third party parallel I/O card. I would probably not recommend using the built in ones for the reason you suggested. Third party/dedicated cards are not that expensive at all.

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General Mach Discussion / Re: Rotary Axis Blues

« on: May 12, 2010, 05:37:40 PM »

Old PC was 1GHz P4 and 1.5G ram...performance with 3 axis was acceptable...4th axis was a struggle.

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General Mach Discussion / Re: Rotary Axis Blues

« on: May 01, 2010, 04:20:57 PM »

Final Resolution:
Two issues were causing the problems I was having with Mach.

1) Make sure that if your code generates neg. rotary degrees select it the general config. to not allow 360 rollover
2) The A-axis sputtering while moving in the x-axis was caused by my old computer not being powerful enough. It seems the rotary calculations with the diameter, feed speeds etc. require a bit more calculating. If your computer is close to the bare minimum (Mine was an old freebie but within specs), it may have problems doing rotary work.

I used a more powerful computer and all rotary sputtering went away.

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General Mach Discussion / Re: Rotary Axis Blues

« on: May 01, 2010, 02:55:28 AM »

Ok, just finished some more rotary milling and while it works...Mach seems to sputter some when rotating the A-axis and moving in the X-axis.  Does anyone know if this is a Mach issue?  It does not sputter when doing regular 3 axis (xyz) work.

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General Mach Discussion / Re: Rotary Axis Blues

« on: April 30, 2010, 09:56:15 PM »

The code is generated by RhinoCam Pro.  After a bit of testing it seems that I have narrowed the problem down to the ROT 360 Rollover command. Apparently having Mach set to Rollover to 0 after 360 seems to cause the rotary and x axis to not move in sync with the RhinoCam code if the code uses negative rotary numbers.  

Note: Mach will still work with the 360 DRO Rollover, which is what made it hard to troubleshoot. It just runs very very slowly and in odd pulse behavior. Allowing negative rollover numbers in the DRO causes Mach to run at normal rotary speed.

Apparently my Mach was setup with the Rollover and I never really bothered to see what the effects were. I thought the DRO was more for information. At least that seems to be the problem. I will update as I go.

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General Mach Discussion / Re: Rotary Axis Blues

« on: April 29, 2010, 12:11:21 AM »

Never-mind, It seems that the g-code that was generated was incorrect.  It doesn't appear to be related to Mach.  I haven't found out yet why the code was causing problems, but when I do, I will reply to this post in case someone else has the same problem. 

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General Mach Discussion / Rotary Axis Blues

« on: April 28, 2010, 05:51:57 PM »

I've spent several hours reading through a lot of posts concerning the Rotary A-axis and CV. 
My A-axis moves in jerky pulses. Any movement in X or Z while rotating the A-axis seems to make it worse.

I read that including G64 in my code as well as making sure CV is set in the general config should help, but it hasn't. Is this normal?

This does not occur when jogging/homing the A-axis. There is no difference in the amount of jerky'ness regardless of whether
CV or Exact Stop is selected.

It also makes no difference whether G64 is in the beginning code to force CV. I did a search through the gcode and there are no G61's anywhere.

I've tried different accelerations, and increased the CV feed rate but that doesn't seem to help. The A-axis still moves in odd slow pulses.

Any ideas?

As an aside, what I am trying to do is mill wax ring using the rotary a-axis. I am mainly cutting the top half of a ring for testing using rotary positions between -90 to 90.

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General Mach Discussion / Re: X Axis Mill vs Gantry

« on: April 21, 2010, 04:31:25 PM »

Both of you are patient! It works now with the x-axis in reverse and then the neg direction unchecked. That seems to fix it without messing with the gcodes.

Thanks  for the help guys, I appreciate it!

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General Mach Discussion / Re: X Axis Mill vs Gantry

« on: April 21, 2010, 03:41:46 PM »

Thanks elpablito! Right now I am testing. I am doing a run with the x code converted to -x. that seems to be working so far. Adjusting the homing messes up the homing directions.

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General Mach Discussion / Re: X Axis Mill vs Gantry

« on: April 21, 2010, 12:15:22 PM »

I tried the reverse option and it does reverse the direction, but does so for the homing switches as well.  Right now, it homes in the bottom left corner when facing the machine. So the reverse causes it to home on the opposite side and misses the home switch altogether.

Doesn't really fix the issue per se.  Would it be easier, or should I say do most people use a negative X movement for vertical mills?