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Tim Wescott Tim Wescott is offline
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Default Sheet Metal Sticker Shock

I just got the following parts quoted (I asked for a ballpark quote, got
a detailed one -- hmph). Here's a rough sketch, with unnecessary detail
_and_ things left out:

http://www.wescottdesign.com/Seminar...iner_Frame.pdf

Over the phone we modified things such that I'd be responsible for the
indicated holes, and the finish would be brushed & clear anodized. The
quote came back at around $36 each in lots of 50.

Is this just what I can expect to pay for these things? Did I go to the
wrong shop? What are the cost drivers here?

I'm trying to put together a training device that I can include in the
cost of a seminar, $36 is more than 1/3 of the worst-case BOM cost that I
was contemplating. I need to know if I can beat this down by being
creative, if I need to bite the bullet and accept a higher BOM cost, or
if I should yank my eldest out of school and put him to work in the
garage bending metal!

The principal of this thing is that there's a counterweighted arm that
swings on a shaft that's pivoted on bearings in the large holes in the
frame. A microprocessor monitors the position of the shaft through a
potentiometer and controls the voltage to a motor/propeller, with the
goal of holding the arm at a commanded position. The hole locations are
assumed to need tight tolerancing because of the apparent tolerance needs
of the pot I'm planning to use, but I'll be re-thinking that decision
here soon.

Thanks in advance.

Sorry this is off topic - would it help if I mention that I'm putting my
vote behind Hillary McBama, with Ralph Paul as her running mate?

--
Tim Wescott
Control systems and communications consulting
http://www.wescottdesign.com

Need to learn how to apply control theory in your embedded system?
"Applied Control Theory for Embedded Systems" by Tim Wescott
Elsevier/Newnes, http://www.wescottdesign.com/actfes/actfes.html