So I am getting really close to having a solidly working machine.
However the issue im dealing with now has to do with the initial move commands.
The move from Home to the start of the project. Its Z move and X and Y are very fast, way too fast and causing the steppers to grind.
Im using the default firmware (latest) but I edited a few values to see if those would work… Clearly they didnt.
Here is what I changed (i have the old values to change them back if need be)
I can only assume these values are NOT the right ones to change.
ANy help would be greatly appreciated.
changed MPE_FAST_SPEED from 9,000 to 1000
MPE_SlOW_Speed from 2500 to 1000
Define MAX_ACCEL_EDIT_VALUES - 6k, 6k, 200, 20k
to 1000,1000,200,1000
Default Acceleration - 400 to 200
Retract - 3000 - 500
Treavel - 400 to 200
literally the latest marlin firmware on the guide page.
So using repetier prior to cut from laptop, then gcode from the lcd to kick off the job
Vcarve has the ability to set the max feedrates, which I set to 8 and 5 for max movement and plunge speeds. However its moving MUCCCCHHHHH faster from Home to Start…
If I can change that in FW, it will always be there vs changing it in the gcode.
BTW, that is from marlin site, not from my arduino although feedrate only kicks in when the cut starts, which seems to be ok… So its a Pre job movement command thats getting me in a tough spot
What setting in the Marlin FW would I want to change to slow this movement speed down? Max feedrate or some other setting because clearly vcarve isnt modifying it or if they are, its not apparent
BTW, many firnwares assume G0 commands are always safe at any speed, because the firmware limits it to the max feedrate. Marlin doesn’t see a distinction between G0 and G1 (by default), so it is safer to set the max speed rates to something achievable, or define a speed rate on each command.
I re flashed it with the original FW again, and now, its moving from home to start of print at a SNAILS pace lol… after that it seems to be good.
This thing has a mind of its own
OMFG I wanna kill this thing…
So I think "ok its just slow getting to first movement, fine. "
first movement goes, first cut goes ok (its off center, which is strange, because pretty sure my holes are aligned… maybe im wrong. ok
After 2nd hole, the thing just takes off and slams in to the top Y, does that for a bit, then slams back to the other Y.
This thing is seriously possessed.
Then I decided to go back in to Vcarve and just delete ALL my toolpaths and start again… of course this led to the Move command pre job to just be fast and both x and Z missed steps like crazy. I know im not far away, but every second i feel like im further lol
so im getting things better
that move command was
T1
G17
G21
G90 G0Z20.320F100
G0X0.000Y0.000
S16000M3
G0X63.500Y52.089Z5.080F600.0
G1X63.500Y52.089Z-1.905F600.0
G2X64.789Y50.800I0.000J-1.289F600.0
G2X63.500Y49.511I-1.289J0.000
G2X62.211Y50.800I0.000J1.289
the bold… So I added the F100 after that move to slow it down .
Reasonably I can easily go to F400-500 without issue…
Im about done with 1 tile of the spoilboard. making headway. ONce I have my spoilboard done, I can test all day long
Also keep in mind that feedrates are “sticky”. If a move command doesn’t specify a feedrate, then the move will be made at whatever the last specified feedrate was. It seems possible that the weird behavior you had on the previous run might have left the feedrate set at a very high value that is being picked up by the start of the subsequent job.
Perhaps… I do know since inputting those F values I am getting consistent results.
However I realized (after trying and failing a lot) on my spoilboard that you MUST do both the engrave shallow spot for the T nut AND the hole in the same job.
If you try to get back on perfect Zero you wont… haha
Yeah its strange why the X and Y return, but Z stays elevated… oh well im running a combo job on this spoilboard to ensure the holes plus depression are good… ive jacked this spoil up so much I may just need to go buy another one haha
Most machines leave the Z elevated so that it doesn’t accidentally drop into the top of the workpiece when the steppers are turned off. It also leaves room for you to remove the work piece without having to move the tool… Think ‘big cnc machine’ where x0 y0 is the back corner of the work piece and you can’t move it easily by hand. Saves time if the tool parks itself out the way.
Yep. does make sense when you think about it that way…
BTW spoil board is done… Need to engrave the one side now, but its great in the place I did both cuts at once, and a mess where i didnt.
may get be by for a bit
btw, what would cause this? lines left to right were cut first.
Front to back, last… Did the bit drop? it started happening midway through, and got worse over the cut.
Probably skipped steps on the Z, as it was climbing out of a hole, carrying the router. If there was a fast Z command somewhere in the gcode like this:
G1 X200 Y200 F1200
G0 Z10 ; Oops, just tried to lift Z at 20mm/s.
Estlcam, with the right settings, will fix a lot of these problems for you.
If you still want to use vcarve, is there a better post processor for it? I know one is linked at the bottom of milling basics. I don’t know more about vcarve.
You can also set the max Z speed with M203 Z400 and then save it with M500. But there may be other problems not using the Marlin post processor.
Ive looked at that milling basics and the corresponding thread regarding vcarve etc. I couldnt make heads or tails of ANY of it haha. It was more confusing than calculus haha.
Vcarve is just a lot more featured for what i want to design… I guess technically i could just export the DXF and use estlcam to cut it.
Although id have to learn estlcam again
although feedrate only kicks in when the cut starts, which seems to be ok… So its a Pre job movement command thats getting me in a tough spot
