R/C Tech Forums - View Single Post - Trinity D3.5 17.5 deemed illegal by ROAR
View Single Post
Old 01-18-2013, 09:13 PM
  #67  
nv529
Tech Elite
iTrader: (53)
 
Join Date: Feb 2008
Location: Belleville, MI
Posts: 4,513
Trader Rating: 53 (100%+)
Default

Originally Posted by Cpt.America
So while they may not be ideal, are you suggesting that these calipers are under measuring by .0003? .0320 is dead smack middle, .0322 is max. .0323 to be illegal.

(i think i got that right)
Yes it is possible they can measure undersize the readout of digital calipers can easily be altered in many ways..

1) They are pressure sensitive, you and I can come up with 2 different measurements using the same set of calipers simply by how much pressure is applied to the test piece

2) They can easily be "zeroed out/calibrated" at any location throughout its travel range by simply pressing the "origin" button. What this means is you can make 1.000" block read .2500" by simply measuring a .7500" block and then hit the origin button. Lets say the wire is really .035 and you wanted to trick everyone on the Interwebz into believing the wire is .032" all you'll need is a piece of paper (roughly .003-.004 thick) to "zero out" on then recheck your part which now reads .032

3) Soft and small test pieces should never be measured at the bottom of a caliper near the blade tips. You can easily indent the test piece which will give you a false reading.

4) Digital calipers round to the nearest .0005"

Last edited by nv529; 01-18-2013 at 09:47 PM.
nv529 is offline