I had a long carve running, over 20 hours. I didn’t want the machine to run over night without someone present if something went wrong. I paused the cave last night and started this morning and the Z axis changed by almost 1/32". (See pictures) I am reaching out to anyone who has run into this problem and may know cause and solution. I think I have an idea, but am not sure.
I am running an factory standard XCarve with no upgrades at the moment.
Thanks in advance
Shane
If it isn’t a mechanical issue, then maybe the wood changed dimensionally after the roughing removed excess wood. Wood has internal stresses that get released when wood is removed. It could have warped. In my guitar building I always let the wood sit overnite on critical things after a good amount of wood comes off. That said, I can’t imagine a machine can run for a great length of time without expansion and contraction of metal parts too. Just a guess.
I’m gunna agree with this being the most probable cause of your issue. The corners being clamped down, and the back against the wasteboard, if it was to move, the only direction it really can move is up. it looks like the freshly exposed surface began to dry and the board cupped upwards. This could be mitigated with a strong vacuum table (but who’s got one of those?) or even some double sided tape in the center section where there are no clamps to keep it down…
You could, after the carve is finished, verify your z zero is accurate where you set it at (assuming you haven’t carved that area away & if you used the wasteboard for z zeroing this would be most accurate still) and this would further indicate that the board moved, not your Z axis.
