From: Snag_one@msn.com   
      
   On 6/27/2024 4:56 PM, Bob La Londe wrote:   
   > On 6/27/2024 12:35 PM, Snag wrote:   
   >>    Am I really going to need to allow for millionths of an inch ? I'm   
   >> looking at an 81 piece set from Shars , a grade B with the deviation   
   >> table for under a hundred bucks . Looks like the biggest variance is   
   >> .000034" , or about a third of a ten thousandth . I can't see any   
   >> project that I might get needing that kind of precision ...   
   >>    I'm considering buying the set just because I've kinda wanted some   
   >> and I think they'll get me closer to perfect in my upcoming depth mike   
   >> project . Since they can trace back to a national standard I can also   
   >> use them to check all my other micrometers , none of which have been   
   >> calibrated for at least 40 years , and in some cases longer than that .   
   >>   
   >   
   > You will probably be fine.  I hardly even use my gage blocks.  I just   
   > CNC machine an angle plate with a stop.  I have a cheap B grade set, and   
   > I miced them (I have Starret standards), and they are as good as I can   
   > measure except the 4 inch which for some reason is almost exactly 4.001   
   >   
   > I have a set of gage pins too.  Most of the time I just use my set of   
   > drill blanks because its faster and most holes I'm checking are nominal   
   > standard sizes anyway.  If they aren't I measure them with an inside mic.   
   >   
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   I'll probably only use them for calibration checks . And only because   
   one of these days something I make is going to have to be a pretty   
   precise fit for something somebody else makes . Gauge pins are on my   
   wish list too . I got a set of thread wires a while back . Haven't used   
   them yet but then I haven't needed a precise thread fit . I have a   
   couple of projects in mind that will require a fairly precise thread ...   
      OBTW , I did order that set of Shars blocks . Under 110 bucks , and   
   there's no doubt that if I waited I'd be paying more .   
   --   
   Snag   
     It's great to be straight !   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)