I’m trying to make a MFT table (MDF top with 20mm holes in it). And because the holes needs to be very accurate, I started to calibrate my Lowrider 2.
I use end stops on all axis. So, I started on the Z-axis by measuring the differences in height along the beginning and end of the x-axis. made adjustments with the M666 command until it was perfect. M666 Z4.3 was the end result.
Then I started with the Y-axis. Made a little dot, with a 35-degree bit, moved 850mm and made another dot. I adjusted with the M92 command until it was perfect. M92 Y100.12 was the end result.
Last axis was the X-axis where I did the same thing, made a little dot, moved 550mm and made another dot. M92 X100.18 was spot on.
Then I started to make some test holes. I drew some 20mm holes in Vectric Aspire and made a pocket toolpath with a finishing toolpath at the end. It took some experimenting with the diameter setting of the bit in aspire to get the right size holes but eventually that worked. The perfect size hole, to fit the bench dogs is 20.2mm.
The only problem I have is that some holes are perfect round and the perfect size, but other holes are oval. Where all holes at the y-axis are perfect 20.2mm the z-axis on some holes are perfect 20.2 but on other holes there 19.8mm.
If they were all undersized, I could understand. But because some are good and some are undersized at the X-axis, I have no clue how to troubleshoot this.