Is there a way to calibrate the work surface location with the touchplate instead of manually jogging down to calibrate? Maybe it’s unnecessary, but it would be more convenient after resurfacing the spoilboard. I imagine it would also be more accurate, which would help with having job z-zero set at bottom of material, like in cabinetry.
Just wondering if this is possible to do or not.
It’s not possible to re-calibrate the spoilboard with the touch plate. It’s meant to be done with the tip of a bit.
I initially thought this was a big oversight but now wonder if it is set up to work this way:
When you use the touch plate to set the x y z origin for a job, does that new z coordinate become the bench mark that the macro calculates the new tool length from after a tool change? If so, then it makes the worksurface calibration less critical because the macro is measuring the new tool length relative to the most recently probed value for your stock setup. You still need to do it but its ok that there is the possibility of a slight inaccuracy due to eyeballing it… is that how it works?
Once you set the work surface with the utils you’re good to go until the next time you resurface your work surface.. it’s one of the beautiful features of the EX controller
Tool length is calculated off of the spoilboard. It’s critical that whenever you surface your spoilboard you recalibrate it.
When you use the touch plate it sets a Z offset from the spoilboard. so if you touch off to a .725 piece of plywood with your touch plate your Z offset will be set to .725. If your spoilboard has not been recalibrated though this number will not represent the correct thickness of your material.
I wonder if someday Avid might consider utilizing the touchplate for calibrating the spoilboard more accurately. I know I read somewhere that that decision was purposeful since some people don’t have the touch plate, but it would be nice to have that as an optional way to do it for those of us that do have the touchplate.
Sometimes it can be a little difficult to get a really accurate reading when manually jogging down, especially with certain bit geometries. I try to use the handy “wiggle the paper” method or use some thin tinfoil to get it as accurate as possible. But the touchplate would make it much easier and reliable I would think.
An old school machinist showed me a trick one time, instead of using paper or tin foil, use a 1/4” steel dowl laid on its side, perpendicular to the tool in your spindle. Its more obvious when you make contact and it wont compress like paper and should give you a more accurate offset.
Or if you have the touch plate, you can take your measurement before you start the calibration utility, write it down on a piece of paper and then when you use the calibration utility, manually lower the z axis until the DRO matches the position you wrote down.
Either way, I agree with you, if everything else is calculated off that initial calibration then it would makes sense to make it the most accurate part of the process.
I use broken router bits for this. If you want to try it, the trick is to jog the tool a little too low and roll the bit under while jogging up, so you don’t press down on the bit and break the tool.
Why can’t you use the touch plate to get the current “height “ of the top of the spoil board. Go to that height, and set top of spoil board from that location? Pull the tool before the move if you lack confidence in your touch plate technique 
.
You’ve got to remember we try to engineer solutions that work for as many people as possible. Not everyone has a touch plate, and not everyone who has a touch plate has it accurately setup, and some touch plates are broken.
The “paper trick” or “scrape the spoilboard with a bit” is actually really accurate and works for everyone that has a machine that moves, and if your machine moves you can calibrate it.
This!
Because as I said earlier, not everyone has a touch plate, a working touch plate or an accurate touch plate.
This is a good idea! I’ll have to try this.
Surpher23 after you tried this would you come back and tell us what results you have? Just curious!!
I would recommend using the procedure as it’s meant to be used. I don’t see a time savings here or an accuracy gain.
I agree with you I was just curious!
Does the accuracy of the surface calibration matter at all?
Typically I use the touch plate to set my zero before starting to work anyway. I think I never updated the surface calibration after flattening it.