20 MM hole is 19.2 MM

1

Okay, so I am trying to make a spoilboard with 20mm holes to hold a Festool dog.

But the holes are coming out undersized.

Using Easle, which is I know is hack, but I’m just starting.

I’m “clearing out a pocket” on a 20 MM hole. The dog is something like 19.6. (I am using calipers)

Any ideas what might be going on?

I’m using 3/4 MDF and a slow feed rate.

Thanks

2

Check your bit diameter…

3

What software are you using.
I did the same thing, then realized In fusion 360 had set it to leave .02 inch which made it to tight.

4

This is one of those times where you might want to dial-in the hole size on a smaller scrap piece first, before you actually cut the spoil board. Try taking 1 or 2 finish passes thru the hole to see if it will come in closer to size, then tweak the hole size in Easel until you find the sweet spot.

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5

I’m not familiar with Easle specifically but the g code generated by some programs is going to be a bunch of straight line segments that resemble a circle when done but might be imprecise when measured. Circular or arc moves would be identified in the g-code as a G2 or G3 command where as straight lines would be G1 commands.

I second Bill’s suggestion of measuring the actual bit size, I ended up with a 6mm endmill in my inventory instead of a 6.35mm one.

It may just be a case where the gumminess of the material isn’t cutting cleanly and you need to oversize the hole in your design slightly or use some sanding to remove the uncut fuzz. I use steel dowel pins in my wasteboard setup that are .500 and I had to machine the holes in the wasteboard at .508 for a decent fit that didn’t require a slide hammer to remove the dowels from the wasteboard. When I cut corresponding holes in my workpiece (usually hardwood) a .502 hole works best.

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