Surface plate calibration group buy - Peoria, IL

I thought I would throw this out there.

I am having Fox Valley Metrology calibrate my surface plate on June 16th. If anyone in the local area wants to have their plate checked, you can bring it to my shop in East Peoria, IL.

I am paying the travel cost for the technician, so you just have to pay for the actual calibration. For my 36x48 plate, that's about $52. They can also lap if the plate is out of flat.

ewlsey said:

I thought I would throw this out there.

I am having Fox Valley Metrology calibrate my surface plate on June 16th. If anyone in the local area wants to have their plate checked, you can bring it to my shop in East Peoria, IL.

I am paying the travel cost for the technician, so you just have to pay for the actual calibration. For my 36x48 plate, that's about $52. They can also lap if the plate is out of flat.

Click to expand...

I'm a long way from East P. but that's useful info, even so, Wes. Thank you!

If that's all it costs, I can probably get my brown granite Grade A 30" X 48" Herman done by a closer service for around triple that figure + portal-to-portal & travel, and should do.

Bought 'right' shipped professionally, and the top of it LOOKS like NEW. No damage or stains, so... well worth it.

Update: first 'local' outfit I research seemed more interested in saving my soul (fat chance!).. or perhaps their own?... than in saving my surface plate, so "still looking".


Wes? Fox Valley doesn't show any branches all that close to you. Travel part of the task is costing you? What? Fair chunk out of a thousand bucks?

Well, they were here and have gone. My 36x48 plate calibrated at .0007 total, just squeaking in as a grade B. The repeat reading was nearly perfect.

It was very interesting to talk to the guys doing the work. I asked about lapping to A or AA. They strongly recommended that I not attempt to lap the plate better than B unless it was in a climate controlled environment. My plate was humped up in the middle. Their feeling was that the hump may well be from a temperature differential in the plate since it was a hot summer afternoon. Lapping out the hump could cause the plate to go out of the A or AA spec if the temperature differential was reversed.

It makes perfect sense to me. The ambient temperature listed on the report was 87F. However, the concrete floor is likely several degrees cooler. I think that if I did the math right, a 2F difference from the top of the plate to the bottom would make the plate .0006 longer at the top than the bottom.

A good sign that the repeat reading was good imo, suggests the dome is even. Makes sense if its a hot day and youve radiant heat beating down from roof, cooking the top surface of the plate. Its not the heat per say thats the problem but the gradient through the plate.
A plate that measures out an easy AA at 25c/25c (top surface/bottom surface) prolly wont be an easy AA at 30c/25c. But Id expect the repeat to look good if zeroed from the plate.
My 3x2 is sitting in a space that has an opaque poly roof atm, great for light but crap for temp control.