Author Topic: Granite surface plate  (Read 4347 times)

Offline philf

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Re: Granite surface plate
« Reply #25 on: October 18, 2016, 05:52:48 PM »
Dave,

0.7 micron is 0.0276 thou (0.7/25.4) - so better than you thought.  :thumbup:

Phil,
Phil Fern
Location: Marple, Cheshire

Offline charadam

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Re: Granite surface plate
« Reply #26 on: October 18, 2016, 06:11:21 PM »
Maybe I'm having a senior calculating moment, but I make it 0.000275591".

Surely (don't call me Surely!) a 4 thou surface plate is no more use than a ploughed field?

Offline philf

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Re: Granite surface plate
« Reply #27 on: October 18, 2016, 06:15:19 PM »
Maybe I'm having a senior calculating moment, but I make it 0.000275591".

0.000275591" is 7 microns.

Phil.
Phil Fern
Location: Marple, Cheshire

Offline PekkaNF

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Re: Granite surface plate
« Reply #28 on: October 19, 2016, 03:12:37 AM »
Isn't it nice, when you clean the surface plate, put a sguare lying flatwhen you slide V-block to meet the square you can feel how the finely ground V-block starts to stick to granite. Gives a little confidence to setup.

Down side is that you have to remove burr on the clock base and when you check your measurement gear all starts look rather shabby when it has more than 0,01 mm of out of plane at 100 mm distance.

Pekka

Offline charadam

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Re: Granite surface plate
« Reply #29 on: October 19, 2016, 07:41:01 AM »
"0.000275591" is 7 microns.

Phil."

Yes, I definitely had a senior calculating moment!

Offline DavidA

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Re: Granite surface plate
« Reply #30 on: October 19, 2016, 08:02:04 AM »
Charadam,

I actually wrote...

..According to the spec sheet the greatest error is 0.7 Micron.  I make that about 0.039 Thou"


.....Surely (don't call me Surely!) a 4 thou surface plate is no more use than a ploughed field?...

Don't you just love those senior moments  :doh:

Dave.