On Thu, 13 Feb 2014 18:39:33 +0700, John B.
wrote:

On Wed, 12 Feb 2014 23:38:31 -0500, wrote:

On Thu, 13 Feb 2014 09:34:59 +0700, John B.
wrote:

On Wed, 12 Feb 2014 19:41:44 -0500, wrote:

On Wed, 12 Feb 2014 19:44:53 +0700, John B.
wrote:

On Wed, 12 Feb 2014 02:18:02 +0000, Bob Lowe
0f8503901d844703eea1acecb7a4938a_1650@exampl e.com wrote:

replying to Ned Simmons , Bob Lowe wrote:
news wrote:

On Tue, 11 Feb 2014 18:51:04 +0700, John B.
I did quite a bit of welding on masts back in the bad old days, mostly
on boats 40 feet and up as well. Halyard winch bases and radar mounts
were the first things that came to mind.
--
Ned Simmons


Okay Ned, I have a question...I don't know how far back your bad old days
were but in the 50's when I needed some aluminum welding done I always had
it done by Heliarc, as if the gas welding flux hadn't been developed
yet...I really don't know this for sure. But now that I am retired my 'To
Do' list has grown to a couple of life times long and I can't get
everything crammed in. I have I think at least 3 gas welding outfits, the
regular industrial, a mid sized venturi air type and a little Map
Gas-Oxygen affair. I haven't gotten around to teaching myself how to weld
aluminum. I see the flux coated gas rod and this is my question....could
this be an easy way to get started on this? Or could you recommend
another starting point? I don't want to bother with getting into the Mig
welding area.

Thanks,

Bob Lowe

I learned to gas weld aluminum in 1951 and it was a bitch. My
suggestion is to arc weld anything thick enough and buy a TIG for the
thin stuff.

The problem with gas welding, and to some extent TIG welding aluminum
is that the metal doesn't change color when heated. You are heating
the parent metal, waiting for a puddle to form and suddenly the whole
thing falls on the ground.

The technique is to keep poking the spot where you intend the puddle
to form with the filler rod. If all goes well you will poke and a bit
of rod will melt off and there's your puddle.

But it is so much easier to just use the TIG or even a plain old arc
welder (with aluminum rods :-).

As an aside, not all aluminum can be welded.


You need a set of cobalt glasses to see the heat when welding aluminum
with gas.

How does that work? What colors do you see?
No orange flair, for one.

Are you talking about some sort of flair from the flux that I hear
people talking about so much? I can only assume that it is some sort
of new fangled stuff that we didn't have back in the early '50's when
I learned the technique, because I never noticed any "flair" using
plain old green welding goggles.

Cobalt Gold - not cobalt actually (better for the eyes) - or better
yet the TM2000 from Tinmantech.com. They are an emerald green. And
expensive.
The Cobalt lens is not effective against ultraviolet, so if you are
doing a lot of welding the TinMan lens is worth while (won't give you
cataracts)

Somehow I get the feeling that you've lost the thread. You tell me
that some sort of fancy glasses let you see the heat when you weld
aluminum; I ask you how that works, and now you are off and running
with non-UV lens.

But how does all this let you see the heat of aluminum when you are
gas welding it?
It allows you to see that very subtle change that happens just
before it flows away - which you can NOT see if you are blinded by
flare.