Height Offset Problem

[RJS100]

For the past two years, I set my tool heights by touching off my tools at a designated position. First I established the height of my master tool (the longest one that I never used), then measured the tool heights of my other tools by touching off at this same position and saving the tool offsets in the tool offset library. All worked great.

I recently purchased the KP-3 probe and thought I would swap the probe for my master tool. Per the manual, I ensured that Parameter 12 was set to tool #100 (my probe) and parameter 17 was set to 0. I followed the directions and recorded the tool height offset for the probe and for my tool #4 as well (1/4-inch endmill).

I ran the attached simple g-code and when it ran, tool #4 did not take .005 off the top of the part, but attempted to seek a much lower position than just slightly below the top of the test part.

The tool offsets in the offset library reflect about a 3.12" difference between the probe length and tool#4 (Which look correct), but for some reason, it is not working. I am surely missing something here.

I have attached my recent report as well as the g-code.

Thanks... Richard

[cnckeith]

hi,

from your description i can't figure out if you are using Z ref at the Z home position or Z ref = the reference tool. sounds like you are mixing the two methods together?

[CNCMaryland]

Why not post a quick video. What you are trying to do is something that most of us do every single day. So you are just not setting things up correctly.

[RJS100]

Thanks. I changed course a bit and decided NOT to use the probe as the master tool. I went back and used a long tool for the master tool, recorded the height of the master then measured the height of the probe (tool #100) and the 1/4" endmill (tool #4). Ran the test g-code and all went perfectly well.

One quick question regarding using the probe. Prior to running the part, I probed the top of the parallel and keyed in -2.497 for the Z work coordinate. Then I used the probe with the single axis setting and probed the top of the part. It indicated 0.0 as intended. Great!

I ran the G-code and the end mill removed the programmed .005 from the top of the part. Perfect.

I probed the top of the part again. This time it indicated something like 3.05

When I probe a particular area using the single axis probing cycle, I thought it would indicate the position relative to the Part 0. This does not appear to be the case. Any thoughts?

Richard

[CNCMaryland]

You see that's the thing. With the probe you do not need a master tool.

Z REF is the Z Home.

Then once you hit F10, and save and make the Z Ref = Z Home. Then you can just measure tools. Measure the Probe, then measure the tool#4.

I assume you are using the regular centroid probing method, versus the ProbeApp by Swissi.

[CNCMaryland]

Thanks. I changed course a bit and decided NOT to use the probe as the master tool. I went back and used a long tool for the master tool, recorded the height of the master then measured the height of the probe (tool #100) and the 1/4" endmill (tool #4). Ran the test g-code and all went perfectly well.

One quick question regarding using the probe. Prior to running the part, I probed the top of the parallel and keyed in -2.497 for the Z work coordinate. Then I used the probe with the single axis setting and probed the top of the part. It indicated 0.0 as intended. Great!

I ran the G-code and the end mill removed the programmed .005 from the top of the part. Perfect.

I probed the top of the part again. This time it indicated something like 3.05

When I probe a particular area using the single axis probing cycle, I thought it would indicate the position relative to the Part 0. This does not appear to be the case. Any thoughts?

Richard

I'm going to check my setup tonight, and report back. Hope that I can help you out.

[RJS100]

Thank you. Yes. I have not installed the Swissi app yet. I must be having a blonde moment. Are you saying that you home the machine, then measure the master tool height when the machine is homed? Then all the tools are measured relative to the homed position?

In a previous post, Uwe noted:

For your type of mill and if Z-home is precise, I set Parameter #3 = 6
This uses Z-home as Z Reference
With this setup you can change the stylus on the probe, or use different probes, and only have to measure the new Probe offset.
Since my TTO is softer than the KP3, I use a solid block with the same height as the TTO to measure the probe.


I do not understand what setting parameter #3 = 6 is and why it is required?

Thanks... Richard

[CNCMaryland]

I'll check my settings tonight and report back. I can tell you now, the term master tool means nothing, so you may as well forget about it.

With the Z at Home position, I then go into the offset library and hit Z Ref. Then F10. (You only have to do this once.) Now the Z Reference is the Top of Z/Z Home/Machine Coordinate Z0.

Then measure your tools including the probe, and that is that. The machine then knows how long the probe is, and how long each tool is, relative to Z Home. That's basically it. I will look into what I have Par, #3 set to. When you measure the surface with the probe, the machine will calculate the difference between its measure length, and the called tools measured length.

[RJS100]

Thanks for the nice explanation for setting Z Ref at the homed position. Everything works well except for when I attempt using z home for the reference. I think it is a matter of getting the correct setting for parameter 3

[RJS100]

I will be buying the Swissi app. I asked him the same question regarding single axis probing, and he said it should show the same results before and after g-code is run as long as you are using the same WCS.

I think this issue is a result of an incorrectly set parameter. I hope someone can help me out with this. I currently have parameter 3 set to 0.

Richard