Zero Z axis Fine Point Bits

[majohnson]

When setting up to engrave small letters, using a fine point bit. What is the easy of zeroing the point. I worry that just running the bit down until it hits the Alumnium plate will damage the bits point.

[ljdm]

Aluminum won't hurt a carbide, or steel bit. I know I shouldn't do it, but my z zero plate is a piece of soft steel, I haven't noticed any damage to the tips of my bits. I am changing over to an aluminum plate just to be safe though.

[beacon14]

I lowered the Z move speed in the Zeroing file for just that reason.

[phil_o]

I've broken too many 60 degree V-bits to use the zero plate any more. Now I use the keyboard option set to lower at .005 steps and gradually lower the bit until it grabs a sheet of paper that I hold under the bit. Not my favorite way to zero but it works and I don't break any bits.

[bcammack]

I would guess that the piece of copper-clad, unetched printed circuit board that we use for our z-zero plate wouldn't be very harmful to the more diminutive bits.

[paul_z]

I use the shopbot Z Zero aluminum plate and have yet to break a tip. I use 60, 90, and 120 bits. I make sure that the surface that I put the Z Zero on is clean so it doesn't try to slip sideways on sawdust or such when the tip hits the Z Zero plate (as well as getting a bad zero).

Paul Z

PS I'm running a PRT Alpha

[harryball]

I used the Zzero plate to zero a 30 degree engraving bit and the tip broke clean off once I removed the bit and dropped it on the floor. ;-)

I too have used the aluminum Zzero plate without a problem, like David I also lowered the touch speed.

Are you using a router or a spindle. Not sure what difference that would make except maybe the speed at which the zzero responds when touched.

/RB

[tparr]

RB/ Nice info; can you tell us how to lower the touch speed?