back to the ol drawing board....

Dan Noren

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started the plaque for pop for fathers day yesterday morning. seemed to be going ok. it had generated 447k lines of code, and was cutting rather smoothly, when i left it had gone through over 115k of the code. then i had to go to a fathers day to-do at the wife's :blah: church was putting on. when we got back about 6 hours later, it was still going, but instead of the smooth moves it was doing, it was moving in fits and starts, from a little over 1/8 to 1/2 inch. it was following the path it was supposed to, but real herky-jerky like that. i'll be putting in a call with the shapeoko people today, any ideas here? almost forgot, when we got back it had roughly 206k of code to go before finishing.
 
For the amount of time your machine had been running, it could have gotten too hot. Heat can cause the motors to hesitate; it can also cause the drivers to shut down - all of which can be intermittent and cause jerky motion. As I recall, you mounted the Arduino/gShield in an enclosure with a fan, so the drivers might be OK.

Have you checked the drive current settings? There are different ways to do it and I chose to measure the voltage at the driver. There's a good discussion of the process in this Shapeoko thread.
 
after a bit of looking around, i may have discovered the problem. it seems that the universal gcode sender has issues with files over 250k lines of code. i found this on the github site after using the search 'universal gcode sender non responsive' in google. the writer of ugc said that it would be necessary to increase the amount of memory in the JVM, as ugc loads the entire program all at once. so, i boosted the memory to 3 gig, and i also found that the system stops the hard drive after 5 minutes on battery, and 20 minutes plugged in, if unattended. so i boosted that to 24 hours on plug in. now to see if that works. as for temps, the spindle was cool to the touch, and the electronics were cool as well. now to find a good chunk of time to test the new settings out in...
 
... the writer of ugc said that it would be necessary to increase the amount of memory in the JVM, as ugc loads the entire program all at once. so, i boosted the memory to 3 gig ...

I assume you modified the line in start-windows.bat. What value did you use in place of 256m?
 
no, didn't get into the start windows.bat, went in through the control panel/programs/java and changed the runtime parameters from blank to 3 gig.

OK. The github article you referenced mentioned changing the startup parameter. When I dug a bit deeper, I found that the "-Xmx" parameter can be changed to increase the memory allotted to UGS. The default is "-Xmx256m". I changed mine to "-Xmx1024m" based on the article. I haven't had any issues such as you described, but the largest gcode file I've had so far was about 180k lines.

Where did you get the info about changing the Java settings in Control Panel?
 
after 12 hrs of running, and at a little over 248k of lines sent over, that darned java snake reached up and bit me again. one would think that with 3 gig of space allocated, that would be enough to keep it from going non responsive.
 
Wow, I have to agree with Leo, that's got to be a biggin. Also what is your safe travel height set to in relation to the highest point of the material? I've found setting that to just above that point saves a lot of time having the z axis go up and down between operations.
 
17x8 inch ellipse, 1/8 inch deep pocket with just letters, nothing fancy. Feed rate of 10 inches per minute. Material used is mdf, with eighth inch bit.

You should be able to go to a 20ipm feed rate with no problem using a 1/8" 2-flute bit. Depth per pass could be 1/16" (half the diameter of the bit). I'd use a spindle speed of 8000 or 10000 rpm.
 
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You should be able to go to a 20ipm feed rate with no problem using a 1/8" 2-flute bit. Depth per pass could be 1/16" (half the diameter of the bit). I'd use a spindle speed of 8000 or 10000 rpm.


Yes 1/16 deep

OK on 8k - 10k RPM on the low feed rate

Definitely no more than 2 flute.

Feedrate wise - you should be 60 to 120 IPM --- 10 or 20 is WAY too slow - you are burning the bit.

If you are pocketing - use the largest bit you can fit into the spindle with a 75% stepover and 1/2 bit diameter for Depth of cut. Then you can easily cut the pocket in a fraction of the time.

After the pocket is completed - change to the cutter you need for the text.

So in this you will run 2 separate programs - one for pocketing - one for the text.
 
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