Hi everybody! This is my first post on this awesome forum, even if i got my x-carve since august. So first of all, nice to meet you all, and thanks for all the great tips! You’re a fantastic community, and i hope i’ll be soon posting my projects and helping others as well.
Now, straight to the point. I’m trying to achieve the highest possible precision on the z axis that this machine is capable of. This is because i need to mill some o-rings grooves for liquid blocking, and these grooves need to be extremely precise in depth. Say 1.4mm deep, not one tenth more, not less, or the liquid might come out.
Problem is, my x-carve cuts 0.3mm deeper on an average basis. This means that measuring the grooves with a caliper, i’m finding spots where it cut 1.56mm, others where it’s 1.65mm, or 1.82mm, or 1.59mm, bla bla bla…
I have read A LOT of posts here on the forum to check for solutions before posting, but as far as i could find, no post regarding z-axis inconsistencies or problems was about one tenth of a mm, but rather more about 1mm to 3mm inconsistencies. I apologize if this was actually talked about somewhere i couldn’t find.
My current setup:
I have a stock 1000mm x-carve, with dewalt 611 router, and a custom made z-plate.
Z-plate is aluminum, sanded down to a height of 9.98mm to 10.02mm (0.04mm is the highest tolerance i measured)
Stepper motors calibrated 3 times.
I squared the machine to the point it looses 0.5mm over a distance of 500mm on x and y axis. Couldn’t make it any better unfortunately, but my tests are on a far shorter length so for now it should be enough. (gotta fix this someday anyway)
Actual spoil board is an additional 3mm MDF board that i sanded down to about 0.05mm tolerance on its surface and set on top of the main spoil board.
I re-calculated and set the x and y steps/mm so it looses about 0.05mm over a distance of 500mm.
I didn’t re-calculate the steps/mm for the z axis since i still don’t own a gauge.
How i’ve run my tests:
I measured the cast acrylic pieces i’m testing with, and they are extremely inconsistent in height. What is supposed to be a 10.0mm piece, ranges from 8.9mm to 10.2mm. (btw where can i buy good precise acrylics in the EU??)
I tried with different cut settings (feed, plunge, depth), basically going down to half the stock Easel settings for cast acrylic, and down to 0.1mm with regards to depth per pass.
I run a lot of test cuts as close as i could to the clamps, so to minimize the spoil board and piece inconsistencies.
End mill is a 2mm, 2 flutes, 3mm shank hard steel from Proxxon, that i clamped using the 1/8’’ precision collet tightened to death
Now, no matter what i try, i always get inconsistent depth cuts ranging from 0.15mm to 0.5mm deeper than what’s set in Easel. As i already wrote, the average inconsistence seems to be 0.3mm.
I know that the x-carve is capable of about 0.1mm tolerance, maybe a little less.
Next tests i’ve planned are to re-calibrate the z-probe, and buy a gauge so to re-calculate the steps/mm on the z-axis.
What in the world can i do other than this?
Oh i’m totally new to all of this, i’m learning a lot but still have a loooong way to go.
I’m sorry for such a long post but i thought it’d be better to give you as many details as i could.
Thanks a lot