AndyW wrote in
:

I just use sheet steel a blowtorch, flux and braze it together. A LOT
easier than bending without the right kit.


I've never done that. Could be a good way to waterproof a box though. In
another radio group someone mentioned that only welds would really seal a box
(in a marine environment, specifically), but a braze goes a long way. I have
brazed. just not used it this way.. Also I haven't thought about galvanic
corrosion with brazed steel before either. I suspect a very good painting
might be in order.

On 17/10/2014 09:43, Lostgallifreyan wrote:
AndyW wrote in
:

I just use sheet steel a blowtorch, flux and braze it together. A LOT
easier than bending without the right kit.


I've never done that. Could be a good way to waterproof a box though. In
another radio group someone mentioned that only welds would really seal a box
(in a marine environment, specifically), but a braze goes a long way. I have
brazed. just not used it this way.. Also I haven't thought about galvanic
corrosion with brazed steel before either. I suspect a very good painting
might be in order.

A lot of modern paints will last forever in the elements as long as the
user repaints any nicks and dings.
I usually braze up a box and clean it with brake cleaner to get rid of
the flux and grease then bung on some paint. Never really had a problem.

Brazing is a lot simpler than welding or bending.

Andy

AndyW wrote in
:

A lot of modern paints will last forever in the elements as long as the
user repaints any nicks and dings.


I like hammerite.. I think it even has some prevention of galvanic corrosion
even if it gets damaged a bit. There are also paintable zinc-based layers
specifically to extent the life of steel. I guess the impossible thing tio
grant is totally maintenance free seals, but many methods likely don't need
much more than one reworking per decade. I just wouldn't trust my estimate on
milage in sea spray.

Brian Reay wrote in news:1207878279435369714.592439no.sp-
:

The ideal finish is anodise and dye (at least I'm pretty sure it is
anodise, perhaps another treatment, certainly dye). A very good finish and
durable. I don't think it is practical at home, partly due to the pre-
treatments. You often see this on commercial alloy products, which have a
very thin, silky, finish. Things like Karibiners used in climbing.

Sulphuric acid and electrolysis... I considered it... But anodising is best
left to those weho specialise in it. I already have acetone, MEK,
isoproponal, ferric chloride, in flasks and cans in my home. I decided not to
temp fate by adding lots of strong acid to the collection.

As far as aluminium's finish goes, why not just leave it bare? Not so pretty,
but it won't change much over a decade or two because all anodising is, is an
acceleration of the natural oxide layer formation (with dye fixed into any
porosity to make it look better). Once that layer is there, being the second
hardest natural mineral known, it just sits there unless something can break
through the thin layer by compressing the soft metal underneath.

One thing I have seen is old TV aerials in advanced corrosion so indications
of worst case real conditions can be known from those. They tend to thin, but
less so in recent years, less acid rain about.. Where they do fail is in
galvanic corrosion where cheap ferromagnetic steel bolts were used on them.
Most clean lengths of bare Al seem to last a very long time despite looking
very frail.

On Sun, 19 Oct 2014 02:47:46 -0500, Lostgallifreyan wrote:

Brian Reay wrote in news:1207878279435369714.592439no.sp-
:


As far as aluminium's finish goes, why not just leave it bare? Not so
pretty,

You can make it look better by using a fine wire brush on it; most easily
done with a wire wheel in a grinder. Just make sure all the scratches
run the same direction. You can keep it from leaving blackness on your
fingers by spraying it with clear plastic afterwards.

--
Jim Mueller

To get my real email address, replace wrongname with dadoheadman.
Then replace nospam with fastmail. Lastly, replace com with us.

Jim Mueller wrote in
eb.com:

You can make it look better by using a fine wire brush on it; most easily
done with a wire wheel in a grinder.

I didn't think of that.. I've done something like it with small laser cases
built in extruded 1 inch square tube though, using emery paper glued to a
flat MDF board. It's a very nice finish, but it's not a method for large
parts, too much work. I used to get numbness from gripping sharp edges under
high pressure, and that never entirely healed. It was worth it at the time,
but no-one could make a lot of them that way unless they wanted permanent
injury. I did try one wire brush at the time, but for whatever reason it
failed, I couldn't get consisteny the way I could with the emery board. That
brush was only good for derusting steel before painting with hammerite. Maybe
a larger and faster one, used lightly, might have worked better, but not on
small parts I think (would have damaged the fine edges).