OT: Sheet metal and UNF screws (was Re: PET and the IEEE-488 interface)

[Pete Turnbull]

On Apr 1 2005, 19:33, Philip Pemberton wrote:

> Shame it's so hard to find #4 copper wire (then again I'm
> probably not looking in the right place). The thickest I've found is
2.5mm
> solid core copper.

It may depend on what you're asking for.  What do you mean by "#4
copper wire"?  4SWG, which is just under 1/4" diameter?  4AWG, which is
somewhat slimmer?  That might be "wire" to the company that runs the
mill that makes it[1], but it would be "copper rod" to most of the rest
of us.  Try a model engineering supplier.

Or do you mean insulated cable?  That would have a cross-sectional area
of between 21mm^2 and 28mm^2, depending on whose wire gauge you used,
and would have a current capacity of something like 150 amps,
continuous, in an enclosed space (like a conduit).  Almost double that
in free air, more for intermittent use.  Try a welding supplier, and
ask for the cable used for earth clamps, or buy a cheap pair of jump
leads.  Or do what I did, and twist 3 or 4 thinner cables together.  I
have a cable that will run about 350A-400A, good for a fairly decent
spot welder.

[1] I once got some 3/8" square silver steel from the local wire works.
 They called *that* wire, too.

-- 
Pete						Peter Turnbull
						Network Manager
						University of York