west wrote:
Thanks to all the RATs for previous advice on custom chassis size. I'd like
to ask if given heavy enough gauge ... which is better for constructing an
amp ... steel or aluminum? Do they each have their own merits? Thanks.
Cordially,
west


I made all my projects of aluminium. Mostly 1.5 to 2mm thick.
Where it was too flimsy I used aluminium Ts or Ls or Us. Self
threading screws or rivets to fasten them to the chassis.
I made frontpanels from 5mm and even 10mm alu. Whished I could
have machined them.
I like to build modules on aluminium panels and then screw them
together into a frame of alu Ls. Use Us for bigger frames.
For smaller projects you can get alu profiles where alu sheets
slide in. Almost no screws to open view. Also I hate to drill or
punch holes into complex, hollow forms. It's easier with alu sheets
instead. And when I mess up I lose just one sheet and not a whole
chassis.
I also like to work with brass and copper but never did chassis
with those materials except for some small boxes which were used
for RF-shielding.

Steel chassis are more attractive for series production because
one can point-weld and do sharper bends. Then galvanize the chassis
for anti-corrosion. But this was always out of question for small
projects.
Nowadays even alu welding is not out of the question provided you
can afford the appropiate welding machine.

The hardest part was always to give the front panel a nice finish.
Brushed alu is nice, brushed brass is nicer. But you need some
contraption to make linear and parallel brush strokes. It just
does not look right when made free handedly.
I tried sandblowing alu and brass but it takes all shine away and
looks dull. It is also very difficult to do evenly. But what looks
nice is sandblowing and then brushing.
With alu you need to keep the temperature down, otherwise the alu
will smear and you get little ripples on the surface which spoil
it all. That is why a rotary brush is not a good idea.

Nowadays I just don't have the time do such jobs :-( .

You might ask on the DIY metal works news groups. There are some
savvy guys.

Kind regards, Eike
--
Lions go to absurd lengths to retain the posession of their skins.
- Stewart Edward White 1913