On 07/03/2014 09:27 PM, Gene Heskett wrote:
> believe I need to figure out a way to certify its accuracy 
> as g2 cut circles seem to have anywhere up to 3 thou, 
> perhaps a bit more of almost random edge wibbles. 
> Difficult when the only dial indicators I have are a 1" 
> travel, .001" scale, and one of the Grizzly .0001" with 
> perhaps a 13 thou range either way from zero.
Well, I always make a rough cut first, then make a finish 
pass of about .010"
to clean up the edge with minimal tool deflection.  Small 
HSS cutters can
deflect an amazing amount without breaking, but you will 
have large
errors.  Solid carbide cutters are much stiffer.

> So, how accurate might I expect to see with an ebay 
> optical scale? Good enough to map these screws? Something 
> like this: 
> <http://www.ebay.com/itm/RSF-Heidenhain-Optical-Comparator-Video- 
> Measuring-Machines-Scale-New-in- 
> Box-/201105192906?pt=LH_DefaultDomain_0&hash=item2ed2cdb7ca> 
> For a $150 bill. Thanks Jon. Cheers, Gene Heskett 
That's only a 10 um scale, hardly suitable for high accuracy 
machines.
10 um = .0004" or 2540 counts/inch.  I'm running 20000 
counts/inch on
my Bridgeport in X and Y, and 40000 counts/inch on Z.

Jon

------------------------------------------------------------------------------
Open source business process management suite built on Java and Eclipse
Turn processes into business applications with Bonita BPM Community Edition
Quickly connect people, data, and systems into organized workflows
Winner of BOSSIE, CODIE, OW2 and Gartner awards
http://p.sf.net/sfu/Bonitasoft
_______________________________________________
Emc-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/emc-users

Reply via email to