I’m making a pair of charcuterie boards that have a half heart cutout of each of them. I cut the board with the half heart outline and expected the piece to fit perfectly in the cutout. It doesn’t fit very well. Its almost an 1/8th of an inch smaller than it should be. I think I’ve done everything correctly on the carbide file but though I would post it here to get a second opinion. Any ideas?
To be clear, each piece is cut from a different piece of wood. I am joining them together after. Not cutting from one piece! Clearly the bit kerf would cause that gap in that case.
I say start simple and make sure the machine is calibrated. Draw a 1" square, cut out a 1" square, then use a set of calipers to make sure its a 1" square.
From the way your pieces appear to interlock, they look small in both the X and Y direction. My first guess is to say double check that you used the correct size cutter. If you tell the CAM to generate toolpaths for a 0.125 bit and then use a bit with a larger diameter than that when performing the cut, it will cut your parts too small.
I’m using the #201 1/4" bit and assuming it is perfectly 1/4". Since its the same bit making the cutout and the piece that fits into it, would that mean the error is cancelled out or since its concave vs convex the error is doubled?
That’s what I was thinking as well. So do you think this issue is from belt stretching? Again I would think that since I’m cutting both the hole and the plug on the same machine that any delta would get cancelled out.
Can you think of any other reason why the plug would be too small by 1/8th inch?
Belt tension (see the relevant step in your instruction manual, e.g., Step 5 Belting - Carbide 3D) Note that the X-axis motor is held in place on standoffs and if those bolts are loose this can cause belt tension issues. Also, belt tension for the Y-axis stepper motors needs to be even/equivalent on each side — a significant difference can cause skipping on one side eventually resulting in lost steps on both. Measuring belt tension, squaring and calibration
and then try off-setting to the outside to add geometry so as to cut as a pocket — where possible avoid slotting and add geometry and cut as a pocket
and consider leaving a roughing clearance and taking a finishing pass.