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The second issue is a little more concerning. Every once in a while, when my machine is making a linear interpolated move at g0 speed, ie rapids, which in standard tuning is 15m/min with pulse rates to the servos of 250kHz, the machine does a stutter. It sounds bloody awful, with a hell of a thump. You'd swear that the machine has just crashed and that steps would surely be missed....but no. The machine resumes without losing steps and maintains perfect reference. This 'stutter' might happen once a week, and I use my machine daily.
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Craig
Thank you all for info everyone!
It helps a lot when sitting alone up in Norway and try to figure things out.
I got hold of an old Multicam 1000 router during the pandemic and replaced all the electronics except the steppers, the drossel (choke coil in English?) and the RC filter.
I put in an ESS, 4 x MA860H and a new power supply.
Since the original power supply was around 36V and I was afraid of too high voltages I picked a power supply of 48V 1000W.
I had no clue on what to set the Microsteps to on the drivers, so I picked 1000 Pulses / rev.
Setting the standstill current to be reduced to 50% to reduce heating sounded smart so I turned on that function.
Tuning the motors was ok when it came to speed; just turn up until they failed and the reduce some 20%. But for the acceleration, again I had no clue and just guessed; Turning it up until it failed and then turn it down.
It all looked very well, and I start running jobs and enjoying my new big work area.
But sometimes I could hear a “clunk” in the machine and the tool skipped a few steps and ruined the material. There seems not to be any pattern on when it was happening.
I replaced the NUC with a fast workstation with lots of RAM and power, but the error kept coming at random times.
Most of the times it failed when lifting the Z axis so I tuned down the feed and acceleration and it got better but not good.
I suspected that there was not enough power when all the axis was moving at the same time, so I mounted a huge capacitor across the power supply
but no change.
Then when I loaded a huge job, I noticed that the “clunk” also came when jogging and it happened every time and was easy to recreate; just load a huge file (35Mb / 1000 000 lines) and there it was, every time.
This problem was “solved” with a tip from Tweakie by turning off the screen update. Happily, I now turned off the screen update and turned up my feed again but ups the “clunk” was still around when running jobs.
I guess that big files and screen updates is a separate problem that comes in addition to my fundamental problem.
As I am creating wood decorations (Viking / stave church style) for doors and windows on Norwegian cottages (see facebook.com/hyttedekor) , and the jobs typically runs a raster of 0,3mm for 12-18hours, I would really like to avoid turning down the feeds “just in case” and be sure that I run on the optimal, safe, feed to minimize job time.
I have found that running the raster along the longest side of the wood, minimizes the chances for a “clunk” but this generates a lot of sanding afterwards. I 45-degree raster is much better.
When creating a small sign and running 45 degrees I experienced that the Z axis was continually losing steps for every cut. The cut was “sloping” downward into the material.
One of the suggestions from Mac tech support was to increase the ESS buffes size from 0.180 to 0.200 sec, I tried that, and it solved that problem.
The problem with big files is still there so I guess that it is a separate problem.
The “cluck” however is also still there at “random” times so I guess that my machine have many separate problems.
What is wrong with my setup?
I really need a setup that I can trust 100% as some of the wood I am using is very big and expensive and it’s a catastrophe if the tool is running off.
• Should I drop the micro stepping?
• Should I increase the power voltage to 70V?
• Should I stop using a common power and give each stepper a separate supply?
• Are windows 11 a problem?
• The PC is on a network (2 network cards) to be able to transfer files to it, must it be disconnected when I run jobs?
• How do I tune the acceleration to optimize it but keep it safe?
All tips are appreciated!