Messages

21

General Mach Discussion / Re: C3 - Index Pulse Card

« on: January 12, 2013, 12:31:35 PM »

I've got a thread started over at warp9 to see whether greg has any ideas. In the mean time I guess I need to break out the scope
 

22

General Mach Discussion / Re: C3 - Index Pulse Card

« on: January 12, 2013, 12:15:21 PM »

I just recently downloaded the released version. I think it is the latest release.

23

General Mach Discussion / Re: C3 - Index Pulse Card

« on: January 12, 2013, 11:04:48 AM »

Hi!

I have tried alot of differnt threads now and they are getting better and better . I tried lower Index Debounce numbers and I think that was a good thing for my equipment.
GBut if a do a long thread, 50mm with 1.5mm pitch, the first 20-30 mm will be perfect but the rest can be a bit off. The pitch seems a be increasing towards the end om the thread...
Any good suggestions for this?

Per

I have been having this exact issue. The thread is perfect for the first 20mm and then it deteriorates.  Did you ever fix this problem??

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General Mach Discussion / Re: Mach Turn Index Pulse and IPR question

« on: January 12, 2013, 09:48:17 AM »

Thanks for.the, comments all. I would agree with potential noise from the vfd but i have taken special care to isolate thee vfd and index leads. The motor power wires are not grounded however so I suppose I could  look into this. What other options should I look into for an alternate to the C3 board? What is the most robust index.pulse solution out there? I'm not abig circuit board soldering guy so a canned solution would be preferable. In the mean time I'll see what options I got on the motor shielding front. Thanks all.

25

General Mach Discussion / Re: Mach Turn Index Pulse and IPR question

« on: January 12, 2013, 02:38:07 AM »

 Correction: The Index LED in the mach diagnostic screen is sporadically being triggered. The LED's on the boards appear to trigger very consistently but the Mach LED is getting maybe 1 in 10 when the spindle in running @ 500 RPM. I've tried all sorts of debounce settings but I don't think that would have any effect on this anyway.

So, index signal getting to the BoB but inconsistently being reported to Mach through the ESS. The RPM readout on Mach is getting its info from somwhere, but if the LED needs to be very consistent for threading to work than this is my issue. 

26

General Mach Discussion / Re: Mach Turn Index Pulse and IPR question

« on: January 12, 2013, 01:51:31 AM »

 I'm STILL messing with my index pulse on this lathe conversion of mine. Per some recommendations off this board I converted the signal from the C3 into differential to the BoB due to some potential noise issues. I painted the index wheel flat black to avoid any optical errors. Mach is configured to allow syncing and has spindle speed averaging. The RPM readout seems to be very stable and doesn't hop around at all. I tried to thread for the first time tonight. The test piece was delrin and I was attempting to cut a RH 1x8 UNC thread 2" long. The first 3/4" or so of thread looks great, but then it looks like maybe one of the index pulses got dropped and the rest of the pitch is shifted over 1/2 of the thread pitch. It seems to correct at the beginning of each new cut since literally the first 3/4" or so looks perfect. It seems to be exactly half the pitch so a dropped index signal makes sense except for the fact that I've got averaging checked. It seems like the first few passes are great, but into the 3rd or 4th pass the thing starts buggering up. It has consistently done it 3 times now. I have noticed that I am getting a very consistent pulse out of the index LED on the C3 board and on the input in the BoB LED, but often times when I'm rotating by hand the LED on the diagnostic screen misses pulses here and there. I suspect there is something going on related to this but at this point I don't know where to look. I'm really desperate to get this machine threading due to a job I need to get out of here ASAP.

AAAAHHHHH!@#!@$!

27

General Mach Discussion / Re: Mach Turn Index Pulse and IPR question

« on: January 03, 2013, 08:35:17 AM »

 I seemed to have fixed the issue last night. I ended up rewiring the optic sensor with shielded cable to the C3 board which actually made the problem worse. I then rerouted the data cable which was running in the same cable way as the spindle VFD output (I know....stupid) and with some debounce I was able to get a very steady RPM signal in the DRO. I monitored the spindle running for half an hour or so without a single spike in RPM, and the threading cycle which was hessitating now cycles smoothly. I'm hoping to actually do some cuts on metal tonight to confirm, but I suspect I'm all good. Once again, improper machine wiring protocol to blame.

SG

28

General Mach Discussion / Re: Mach Turn Index Pulse and IPR question

« on: January 02, 2013, 09:57:54 AM »

 Good info Hood. I'm using a CNC4PC C3 index pulse board with a H21A2 phototransistor and a slotted disc. I've done the slot calcs and I'm at around 600us pulse width at 3000rpm. The sensor comes with a 6' lead already soldered on which is touted as being shielded, but it isn't. I need to swap it out for a shielded wire and ground it to the star point. The sensor wire is running right next to a bunch of power wires between 12V and 200V, so this is an issue. Thanks

SG

29

General Mach Discussion / Re: Spindle Index Pulse Problem

« on: January 02, 2013, 09:50:37 AM »

 Did you ever get resolution to this issue? I'm experiencing similar issues.

SG

30

General Mach Discussion / Re: Mach Turn Index Pulse and IPR question

« on: January 02, 2013, 08:33:12 AM »

 Interesting. So when threading it is also just looking at the speed at the beginning of the cycle or is it looking at it with a higher sampling rate? I was playing around with threading last night as well and during a 10 pass threading cycle I noticed the Z axis was stuttering from time to time. I was once again cutting air but I'm certain these hessitating moves would have trashed the thread. The Z axis doesn't demonstrate this behavior any other time. I have noticed that my index readout on the screen periodically blips to a much higher RPM reading, and then quickly returns. I suspect I have noise somewhere but also need to make sure the slots in my disc are wide enough.  Debounce doesn't seem to help the issue in any significant way. If what you're saying is true than maybe I have something else going on because once the threading starts a blip on the RPM readout shouldn't have any effect on feed rate.

It is remarkable how different Turn is from Mill given that they are technically the same program. I feel like a newbie even though I've been using Mach Mill for nearly a decade.