Centroid Community CNC Support Forum

In the tool table for your probe tool, what do you have the probe diameter set to? It sounds like you have this set to zero instead of the probe diameter. You should not have to add or subtract anything when setting a tool to either side of the probe.

Where/how do you set the probe as a tool? This is not covered in the lathe user manual that I see..

Page 6 of the lathe manual v4.20 https://www.centroidcnc.com/centroid_di ... -v4.20.pdf

Parameter 281 - Tool Touch-off Device X stylus size
Parameter 282 - Tool Touch-off Device Z stylus size
Parameter 283 – Auto Tool Touch-off safety clearance

I have #281 & #282 set to 9.5mm (3/8"). This auto touch off works fine for external tools.

The process and parameter setup is different for lathe and mill. For mill you set the probe diameter, as it is spherical (but for tool length offsets you use a flat pad). For lathe the probe tip needs to be a different shape (the Centroid and my DIYO probes have cylindrical / disk shaped tips), hence #281 X stylus size (diameter) and #282 Z stylus size (length or thickness).

Works perfect for me, no manual adjustment, but probe is in centerline of the spindle.

Uwe

Tom mentions the tool probe being in the tool table. I know how that works on my mill. This is a lathe conversation and I don’t see anything in the manual about a lathe tool touchoff being in the tool table or assigned a tool number..

Muzzer is right. I was mistaken. Lathe probe sizes are controlled via parameters.

Wizard page to setup a Lathe Probe with Acorn.

I wouldn't waste time using auto touch off. When I touch off a probe in my lathe it never cuts on size. Probe touch off is only really useful for super rigid machines with no flex. If you have a small lathe don't waste your time, the most accurate way is to make a skim cut as it add in all the flex of the the machine and cutting forces.

vw_chuck wrote: ↑Wed Dec 07, 2022 8:31 am I wouldn't waste time using auto touch off. When I touch off a probe in my lathe it never cuts on size. Probe touch off is only really useful for super rigid machines with no flex. If you have a small lathe don't waste your time, the most accurate way is to make a skim cut as it add in all the flex of the the machine and cutting forces.

I am getting ok results with the probe:

Set Part X Ref with a skim cut like a usual finishing cut
Set TT X Ref with the same tool
Measure all tools

This way the deflection is calculated.

For most tools I need to correct less than 0,02mm

Uwe

I notice the positive rake tooling vs negative rake tooling is WAY off. Then throw in some aluminum inserts which cut smaller on OD the deeper the DOC I take. It turns into a crap shoot on my machine. It is easier to just skim cut for setting up the offsets.