below is an image of a box I made, it came out well, but the lid will not fit as the box hole is 0.5mm too small, and the outer edge of the lid is 0.5mm too big. The difference in accuracy seems to be the same on all sides of the box, holes are 0.5 too small, and parts 0.5 too big. I am wondering if this is deflection of the bit, or maybe belts too tight? idk. I also attached my estlcam settings.
my build is 24"x 26"
and I am using a generic 1/8 2 flute carbide end mill
it looks like the problem is the size of your bit. check the circumference of your bit with a caliper and what is the same as the one you have written. a bit of 1 / 8inch in metric is often 3.18mm but in reality it is 3.175mm
I have tried to input 3.175 in estlcam, but it just rounds it up to 3.18, regardless I don’t think that small of an amount would cause 0.5mm difference in part
ESTLCAM rounds the bit sizes for display purposes. So even if you put 3.175, it will display 3.18.
Did you use a full depth finishing pass?
Also it is wood, you can not do a perfect fit (well most materials actually) wood does compress a tiny bit when doing any operations to it.
I would double check the grub screws on the motor pulley, while milling, there might be enough force to shift them if they’re loose.
no, i do 8mm finishing passes on the 3/4 plywood, is that too much?
I just changed my bit size down to 2.65mm and it seemed get the parts slightly closer too the right size, which is weird because i measured the bit and its exactly 3.18! ><
Get a scrap piece of mdf and stick it to your spoil board. Then drill a hole straight down and back up. Quick gcode would be
G0 Z-10 F600
G0 Z0 F600
Then using another 3mm end mill stick the non-sharp end into the hole and see if there’s any wiggle room, if it goes in at all. Since the error is all the way around, I’m thinking it’s the end mill, and not something mechanical. It could be a steps issue as well, but that would be odd.
