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Probe Cal Reference length

bdrmachine

Aluminum
Joined
Mar 21, 2017
I purchased a used TM1P with the probing option. The tool offset probe and the spindle probe are wildly out of calibration. I don’t have a reference tool of known length to use to re-calibrate. Is there a way around this without purchasing some expensive tool setter or pricey test bar? Are there (fair priced) CAT-40 reference tools in the low hundred dollar range?
 
Use a tape measure or scale from the top of the V flange to the reference tool's tip. You can use a gage pin or dowel pin in a tool holder... whatever's handy. It's only a reference number... all tool lengths are based on the probe length, which is calibrated after you use the reference tool, RELATIVE to the location of the tool setter stylus.

If you're using the same reference tool to calibrate the tool setter diameter, make sure you have as close to zero runout as possible.
 
I purchased a used TM1P with the probing option. The tool offset probe and the spindle probe are wildly out of calibration. I don’t have a reference tool of known length to use to re-calibrate. Is there a way around this without purchasing some expensive tool setter or pricey test bar? Are there (fair priced) CAT-40 reference tools in the low hundred dollar range?

on a mill with tool removed you can use gage blocks to measure spindle face to table. then use probe to measure table and compare dro numbers ?
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not unusual if spindle probe uses length comp to adjust the length comp or at least thats what i have done before when .001 or .002" off
 
Use a tape measure or scale from the top of the V flange to the reference tool's tip. You can use a gage pin or dowel pin in a tool holder... whatever's handy. It's only a reference number... all tool lengths are based on the probe length, which is calibrated after you use the reference tool, RELATIVE to the location of the tool setter stylus.

If you're using the same reference tool to calibrate the tool setter diameter, make sure you have as close to zero runout as possible.


+1, you do not need to buy special tooling. I personally have a gauge pin in a collet holder; I have it running true and have the end ground flat. You can use a rough measurement as Matt suggested for the length, but I personally prefer to measure the actual gauge length and input that value into the calibration cycle. I have this tool set aside for calibration purposes only.
 
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many operator manuals will show using gage blocks and using table surface to measure tool lengths comparing to spindle face the measurements
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nice to have a test bar, just saying it can be done without one. test bar more useful for determining if spindle tram (alignment) and or runout is out of spec in my experience
 
i also got a smaller 1" dia test bar with a morse taper. its length changes based on how much pressure used to push it into taper.
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i have seen .008" length changes before. just taking it out of morse taper and cleaning and putting back in and seating it with moderate force. i am guessing somebody in handle mode touched machine and it got pushed in extra. cnc often puts tons on things
 
+1, you do not need to buy special tooling. I personally have a gauge pin in a collet holder; I have it running true and have the end ground flat. You can use a rough measurement as Matt suggested for the length, but I personally prefer to measure the actual gauge length and input that value into the calibration cycle. I have this tool set aside for calibration purposes only.

I did this as well when I first set up the machine......then I needed the collet holder for a job!

Having the dedicated tooling makes it nice, always available! I don't have to worry about taking the holder for an emergency job, and the cost was very reasonable.....

Kevin
 
I prefer the "less accurate" way of a tape measure hooked on top of the flange. When setting tools that have to rotate, that is how we measure the tool for the height input in VQC (or to record in a tool setting program), so everything matches perfectly. I can see needing an accurate gage length if you're using an offline tool presetter though.

I have two of the Mari Tool master tool deals, but they are only used for checking spindle runout and taper contact.
 








 
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