Changing probe location for HE280

[bvandiepenbos]

So, I have been playing around with SeeMeCNC's probe board, changing location of probe for horizontal radius.
By default the v3 probes center and near Z tower to calculate HR
I was very curious to see if value changes with location. Yes, not surprisingly it does.
To change location you simply change values in eeprom for "Z-probe X3" & "Z-probe Y3"
Send G68 to only do HR probing.
The link to spreadsheet data I have collected so far...
https://docs.google.com/spreadsheets/d/ ... sp=sharing
Basically the biggest difference seen is opposite the X & Y towers, the worst being opposite X.
Particularity interesting because these areas are always the most problematic.
Anybody else interested in trying this on their machine and posting results?

also, G69 probes only for end-stop calibration
G30 for Z height.

[kraegar]

If your build is 100% perfectly square, I believe they would match. Also guessing that's not possible in the real world.

I posted in the Mods area a firmware tweak that will let you probe any point on the bed, and use dc42's delta least squares webpage. (The firmware change doesn't break anything seemecnc is doing, it just adds a bit extra to probe any point). With a "not perfectly square" build, you will probably get better results using the delta least squares page.

[DerStig]

If your build is 100% perfectly square, I believe they would match. Also guessing that's not possible in the real world.

I posted in the Mods area a firmware tweak that will let you probe any point on the bed, and use dc42's delta least squares webpage. (The firmware change doesn't break anything seemecnc is doing, it just adds a bit extra to probe any point). With a "not perfectly square" build, you will probably get better results using the delta least squares page.

Do you have a link to the post? Thanks

[kraegar]

http://forum.seemecnc.com/viewtopic.php?f=35&t=10757

[DerStig]

http://forum.seemecnc.com/viewtopic.php?f=35&t=10757

Thank you now my coding illiterate self will try to understand all of that and not screw up my printer!

[kraegar]

Yeah - the 4 point probe that seemecnc does works fine if your printer is built square and your belts are tight. I got improved results using that, but your mileage may vary.

[mhackney]

In general, one should not rely on calibration to fix basic mechanical problems. I've done lots of testing of moving columns and leaning them, etc and calibration is surprisingly robust to what you might think are big problems. The thing that perplexes me are issues like "low" or "high" spots at odd places between but not exactly between columns. I've studied this on my V1 for several years, have replaced carriages, arms, effector, belts, steppers, etc several times each and I still have a "low" spot that has basically been in the same area but has disappeared and reappeared on several occasions. And this machine is about as square and plumb as I can get it using precision squares, gauge blocks, etc.

Brian, you mention that changing the probing locations gave a different HR result. Did you mechanically adjust your endstops so your endstop offsets are <5 steps?