So, for my day job I'm working on a circuit board design to replace
something which features a heatsink made from aluminum angle. It's 1" x
1" x 1/4", with nice square corners everywhere (radius < 0.02").
Up to now I've been blithely assuming that this is an off-the-shelf item
that I can get anywhere -- but it looks like it may be harder to get than
that. Worse, I'd really like to extend the heat sink another 1/2" or
even 1" under the board, while keeping the outside leg at 1".
So I want to specify something that won't have their mechanical engineers
muttering under their breath _too_ much about @#$% EEs with time on their
McMaster carries aluminum angle, but it describes the inside corner and
the inside ends of the legs as "rounded", without saying what the radius
is. I can handle a radius on the inside corner, but that radius on the
leg takes away from area that I want touching my board. Furthermore,
McMaster only carries angle with even-length sides.
So my questions are:
Is there any commonly-available aluminum angle that has corners that one
wouldn't describe as "rounded"? From who?
If I must go with rounded corners, can I expect that there is a
standard? What is it? Is there a place I might find it on the web?
(Machinery's Handbook doesn't seem to list anything like that).
Is there any commonly-available aluminum angle with uneven leg lengths?
I'm specifically looking for 1" x 1.5" x 1/4", or 1" x 2" x 1/4". From
Any notion of how much it might cost to have a machine shop take a larger
angle and whack it down? These need machining anyway: they have to be
cut to length, then drilled on both webs and tapped on one -- so it would
be a case of "while it's in the machine anyway, make one or two
additional cuts". Precision is nearly nonexistent: +/- 0.05" would be
fine, and finish wouldn't be a huge issue: as long as the edges are
deburred and the cut side isn't so rough that it draws blood when handled
things would be fine; I would expect that a decent shop with even a
minimal sense of pride would insist on a much better finish than
necessary to get the job done.
10 years ago