Thanks for info on multi-pass. Maybe I need to go with that instead. I does seem like the bit is at ease with my ipm at one pass on this lite ply, but perhaps it's not really. My question would be, if the material is being forced a bit, will that cause these issues? I will do multi-pass to see. I'm using a Rocklear 1/16 bit that has a 1/4 drive. Got my Bosch Colt set at speed 5.

Mark, also bought a new USB connection and have checked out all my motor connections. Seems good. Probably will do another test this weekend.

 

I just ran a test piece of pink foam. It was single pass at slower rpm.

Hooked up the new USB cord.

The parts in themselves were accurate except for one piece that showed the same error as before. I checked the G-Code file at the specific location, it looks as though the virtual spindle is doing exactly what it's supposed to do on the path.

What happened this time also were parts running into parts. Not too much distance but still there. Happened about 4 times. These were different run ins than the last cut.

I may disconnect and reconnect all my motor to board wires and try again.

Also, I may swap computers and see also. My PC is vintage 2000, so drivers may be some problems? I DO notice I'm not seeing all the lines when I open my cut file, although the software runs and the machine follows along-generally speaking :roll:

I'll post a pic after I highlight the cut paths on the foam. Hard to see right now.

If you guys think this is a connectivity and signal issue, I will pursue that direction. Which means wire connections and maybe trying a different PC.

 

Here is the pic of the foam test cut. I drew in ink on the foam and enhanced the contrast so its more visible. Seems like all the parts cut accurately except one part. Circled are the parts running together. I'll try multi-path and see, but I remember it made no difference before when I tried it.

Next will be reconnection of all wires, then a different pc if that's no good. Attached files

 

Looks very similar to an issue I had

ref this thread: viewtopic.php?f=253&t=2826

Actually, I sometimes still get this issue. I don't belive it is a software issue.
The problem surfaces when running lenthy programs. I am led to believe this is a actually a stepper driver card issue. I think what happens is the card unlocks then relocks the stepper motors while running the program. Which would make you think its missing steps.
In my case, it started as a few flaws showing up then evolled into the eventual full blown failure of the stepper driver card.
When I run heavier stock like 3/4" foam, the machine's return to zero was off on the Y axis buy as much as 1/4". The machine was returning to zero just fine but the stock was is actually walking in the rollers.

 

Yes, it sounds like this is what's happening to me also. I really only get these failures from larger cut files, after a period of cutting time into the file. I'm going to re-install my wires connecting to the driver card before going on. The only thing I can think of is heat buildup causing issues somehow?

 

20 is a good number for acceleration. Some people turn it down even further but it's not necessary

 

I'm back after more tests.

Frequent things that still happen off and on. It's unpredictable.

Finish cutting a small file. 2 pieces in the file. 2nd piece path doesnt end where it started. off by 1/8.

After file finished. y axis jogg is not smooth at all (don't know the term, like instead of doing 10 steps, does 1 step.) the motor itself is doing this.

x axis motor not working.

turn off machine and on, still the same.

reboot software, then x axis joggs fine. y-axis still rough.

what is the deal here? Sometimes things are good, sometimes bad. I'm sure connections are OK.

Not ready for prime time unfortunately. Back to paying for a laser-cutting service.

 

Try moving the y axis without the machine on. My machine started moving kinda jerky on the y axis. I found the lower guide bearings had clogged up with foam particles. Cleaned them out and the axis was back to running smooth.
I was cutting some 1/4" holes in some parts and they were so out of round it was almost comical. It wasn't the machine, it was the software as you could see obvious jumpy movements. Also the parts had a radius on the corners and all of them had one corner that was smaller. And it was the same corner on every part.
My parts at least now are cutting accurate except anything feature that is a circle,radius or spline.