CNC Shark accuracy is off

[edowney]

It's an 1/8" bit I bought off of Tools Today. I did measure it albeit with a ruler but it's a standard 1/8" bit.

[edowney]

I just did a test cutting a 3/4" pocket circle with the 1/8" bit which is what I used when I make a spoil board. It too is off by 1/16" of an inch. which, yes, makes it sort of sound like there might be something wrong with my tool definitions maybe?

[jeb2cav]

At this point either tool definition, cutter is not really 1/8" diameter, or with the pocket toolpath configuration - show advanced or all options - the Pocket Allowance has a value in it other than 0.0.


If you create a square - doesn't have to be 6 x 6 although that is a good size - and create a profile toolpaht - Outside/Right - is the box correct?

[monitoringpost]

At this point either tool definition, cutter is not really 1/8" diameter...

That's what I'm thinking - until you mic the bit properly I don't think you'll know for sure. A ruler isn't accurate enough. I have a Onsrud bit that's supposed to be 1/8" or 0.125 inches in diameter that when mic'd is actually 0.115. That translates into 0.020 off or slightly more than 1/64" if I input its diameter as 0.125 into my tool database. This plus other very very minor differences could all up to your 0.0625" difference!

[Kayvon]

If you don't have a good way to measure the bit (and if you're using a ruler, I'm guessing you don't), do you have another bit you could use instead?

I'll echo monitoringpost: I have a quality Whiteside bit that's supposed to be 1/8", but is actually slightly smaller. It's perfect for everything I do except precision holes, which I end up widening with the correct bit on my drill press.