I’ve been doing a lot of cuts through solid maple lately. It looks like I’m losing steps on both my X and Y axis when I’m cutting front left corner. I’ve checked all my belts and v-wheels and they seem to be good. Any suggestions/guides to sort this out?
You’ll need to decrease forces on the cutter.
Can you share your endmill specs, feedrate, rpm, depth of cut?
2 Likes
1/8 - 2 flute down cut (I’ve used an upcut with the same results)
60ipm
10k rpm (makita router 1.5 setting)
1/8 depth of cut
I actually think I’m losing the steps because of rapids. I don’t lose steps anywhere else on the machine. My cuts are the entire size of the bed.
That’s a 0.003" chipload at 100%DOC…which is a bit aggressive for hard wood in my book. The poor chip evacuation of downcuts probably does not help, especially if you are slotting ?
I would reduce DOC to 50% (1/16"), which is the most direct way to reduce cutting forces, and see if this changes anything.
Any chance you might be positioning the stock too far left/front of the work area, and at some point during the cut the endmill reaches the limits and you lose steps there while contacting the left rail/front plate ?
1 Like
I should mention this is an S3 XXL with a Z-Plus
I can try the 1/16, but i’ve run at 50% and it still does this. The part where I am losing steps is 9 small .25" circle pockets that are only .125" deep.
I’m definitely not going too far left with my stock.
I really think i’m having an issue with the machine not being square/belts/v-wheels.
You could try dropping the max speed for rapids down a bit through the MDI page. I think the default rapids speed for grbl ‘v1.1f’ in the shapeoko is 10,000 mm/min (it used to be 5000 mm/min in grbl ‘v0.9g’).
I just installed Carbide Motion v5.21 a few days ago (from 2 years on v3.68) and dropped my max speed to 8000 mm/min, I am much happier with the sounds of the steppers at that speed…
To do that first open a log window, then type $$ in the MDI entry field and click on send. Make note of the values (copy and paste them into microsoft notepad and save it as initial values).
Then, in MDI, type $110=8000 and click on the send button.
Then type $111=8000 and click on the send button.
You can make adjustments to the z-axis as well ($112=…), but I didn’t because I just installed a z-plus (has different settings from belt driven).
You can also make changes to the x, y, and z max acceleration, but I don’t want to tell you to do that as I haven’t done that myself. However, if nothing else ends up working, it does seem like a logical place for steps to be lost if forces exceed belt friction on the teeth.
Maybe someone else can ad their advice as well…
4 Likes
Turns out we were all wrong. The left Y stepper motor set screw was loose 
3 Likes
This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.