Z Plate - Something Odd Happening.

[thecustomsignshop]

Get this one.

When I z - 0 using the SB plate just about every bit is zeroed correctly, but, I have one EM .125 bit that always z's about .01 lower than is should. Odd. Anyone ever have this issue.

Again, seems to only be this one bit and on either of my 2 machines, same result.

[harryball]

I had a similar issue with a V bit. It has a VERY sharp point and I noticed on one project it was leaving lines on the spoilboard where the end mill bit was not. I would have never noticed except it was a cut through project. My theory is the point of the bit is cutting into the Z plate every so slightly.

So... does this one bit have sharp points per chance?

On a more outlandish idea... the speed of electricity is not infinite... perhaps this bit has more resistance to it.

Robert

[steve4460]

Are you Z Zero with the dust skirt on it ?.
I have notice that sometimes the dusd skirt will move the plate a little on the second pass .

BOT on
sv

[thecustomsignshop]

Hey Stephan, yes, I am. I normally try to hold it in place, but that could be a consideration.

Robert, good point. I'm going to do a controled test on a number of bits to see what happens....

Good thoughts guys, thanks.

[richards]

You might consider modifying the Z-zero file a little to slow the move speeds a little on the second pass. Sensing takes a finite amount of time, and the amount of travel from the time that contact is made until the sensor detects that contact can lead to minor problems.

[thecustomsignshop]

That is a good idea, will try it today, thanks.