Surface Plate Calibration Collaboration (or Plate Fest)

[Catfish6945]

i wish i didn't have to go to San Luis Obispo yesterday and miss the party!
thank you very much Bob for coming up with the great idea of joining forces to get this done.
now the real fun begins!

Mike,
You missed it. I left you Scribe with your plates. I had to give one to Bob so he wouldn't take yours.

 

[eeler1]

I've been to your 'shop', where did you get all that open space? Really nice project. Wish I had a beat up surface plate to fix.

 

[Bob Korves]

I've been to your 'shop', where did you get all that open space? Really nice project. Wish I had a beat up surface plate to fix.

Hi Jon,
It's a three car garage, just kicked my ONE car out for the plate fest. I did realize that I never posted any pics of the rest of the shop and the machines, maybe next time...

 

[extropic]

Yes, Meehanite cast iron laps and diamond powder of various grits.

Mine was the worst, at 1.5 thousands out, a "bowl" in the center. I had guessed that, having bought it off a rack behind a machine shop, covered with dirt and grime and then chasing a tenths indicator around it. It took about 20 minutes to half an hour to calibrate. Ulma Doctor's two plates were good enough that they would have passed class B as they were, and they finished at 20 millionths after 15 minutes work. The smallest plate actually took longer because the lapping plates being larger than the surface plate causes overhang which makes the work more fussy. The larger 24x36 plates were fairly flat, but one of them had a twist in it (see writing on plate), and that one also took longer. All the surfacing was done with cast iron lapping plates.

Thank Bob,

And thanks again for posting about the "plate fest" idea. It's perfect for those of us who would like to save some $$ where we can.

 

[itsme_Bernie]

Holy crap what an Awesome idea!!! I have to reread your first message, but I'd like to learn how do I arrange for this in Northern New Jersey! I'm totally up for having a surface plate calibration event!


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[Ulma Doctor]

here's a video Randy Richard made from the experience!

i'm sorry i had to work and was not present for the surface plate re-calibration party.
Thanks again Bob for the great idea!
(pictures 1,3, & 10 show my surface plates , a 12x18 Escondido Blue Granite and a 18x24 Escondido Black Granite)

 

[bfd]

I always assumed that my plate is ok. I have one of the $88 18 x 12 plate from enco. never really used it. but it is a really good idea bill

 

[Bob Korves]

I always assumed that my plate is ok. I have one of the $88 18 x 12 plate from enco. never really used it. but it is a really good idea bill

Bring it over, Bill, and we can spot it in to my newly calibrated plate by using some spotting ink for scraping. That will likely tell the tale, at least pretty well...