RST Engineering wrote:
"Ernest Christley" wrote in message
And if you could put the bend within 10 mils of where you intended every
time, would anyone care?

I care very much. If you got a chassis from me and it had 20 mil gaps in
the corners, you'd think I was the sloppiest designer in the world. All my
freshman students bend within 10 mils on everything to pass the course.
Most of them can hold 5 if they try.



Oh, no. Now you done gone and did it.

First, I need to make sure we're talking apples to apples. A mil is
1/1000th inch. Consulted http://www.onlineconversion.com/length_all.htm
just to make sure.

1 mil = 0.001 inch [international, U.S.]

I have here in my hot little hands (queue paper rattling for the ditto
heads) one gen-you-wine "RST-443 Panel Mount Intercom", the serial
number being 1014, which went together perfectly and works wonderfully.
I LIKE it, and you can't have it back. Starting at the front right
corner and proceeding counter-clockwise, the gaps in the bends on the
lower half of the chasis measure .020, .030, .032, .035. The bends in
the upper half required a different technique. The edge of an envelope
fit loosely in the gap of the rear corner bends, the envelope measuring
..010.

We must be talking different measurements; either that, or I have
extremely low expectations and you're headed out to chew some hides in
your quality control department. 'Cause, I think this box is tighter
than a cheerleaders butt.


If the designer calls for that amount of accuracy in anything other than
bearings, it's time to find a new designer.

I *BEG* your pardon? In my part of the world, 0.0 is within 50 mils, 0.00
within 20 mils and 0.000 within 5 mils.


I have only a couple measurements on my set of plans that call for a
specific tolerance. One is for the pins locking the gear leg halves
together. The other is for the wing lock pin. The rest are just
measurements with the smallest being with 1/16". Everything broken down
into feet, inches and fractional inches. But no "plus or minus"
anywhere. So I asked a recently retired machine shopman and sheetmetal
worker, because, heh, if you can't trust somebody that's been doing it
40yrs, who can you trust? He told me 1/32" if not specified. Does the
difference come down to how the numbers are specified? Fractional
inches resolve to 1/32, and decimal inches have the tolerances you state?