[TheForge] Last two events...long

Thu Jul 31 11:05:00 2003

An easy way to determine welding heat, in any ambient light condition, is to
taper a fine point on a 30" piece 1/4" mild steel round stock.
When you think the billet is about up to welding heat, touch the fine point
of the rod to the billet, if it sticks, the billet surface is at welding
heat.

If the billet is made up of several layers of steel, it is often beneficial
to remove the billet from the forge for 30 seconds or so for a few times
during the initial heats, to insure that the interior layers of the billet
are all at welding heat.
This is called soaking the billet. If you don't do this your billet may
start to delaminate.
Chuck
----- Original Message -----
From: "Bruce Freeman" <[email protected]>
To: <[email protected]>
Sent: Thursday, July 31, 2003 7:34 AM
Subject: Re: [TheForge] Last two events...long

Phlip,

I feel I only "mastered" forge welding a couple years ago.  Since then most
of my welds have been decent.  However, at the fair this past weekend I
could not for the life of me make a weld.  The problem was sunlight -
indirect sunlight - sunlight my eyes see, even if it's not on the piece.
Sunlight is about 6000K, whereas welding is done around 2500F = ~1650K.
Curiously, the problem is not that things look too hot, but that they look
too cold.  I think part of it is that in sunlight, you see the scale on the
piece illuminated by sunlight, and not the radiation from the piece.  I may
be way off base on my reasoning, but I know there's a difference between
working in sunlight and working indoors.

Indoors, I find the welding heat easy to judge.  I can't use the trick that
the piece looks wet (it does) because the "wet" look is obscured by the flux
I use, which IS "wet."  Rather, I use the trick that the iron, at welding
heat, "disappears" in the fire.  You can see it only when you move it.
This, of course, presupposes that the FIRE is at the appropriate heat, but I
don't find that any particular problem to achieve.  Throughout heating to a
welding heat, I'm staring at the piece in the fire, so that's not the issue.

One beginner's error is failure to "soak" the piece.  If not enough of the
iron is hot - or if only the outside of the piece is hot - there isn't
enough time to complete the weld before the piece cools.  My "rhythm" is to
take the piece to red, remove it from the fire and apply flux (borax),
return it to the fire and heat to a near-welding heat � then keep it there
long enough for that heat to penetrate the piece.  (It's worthwhile to point
out to beginners that they are holding the other end of the piece in their
bare hand.  Iron does not conduct heat very quickly, and that is as true
from outside to inside as it is from one end to the other.)  Finally I crank
the fire a little more, the piece disappears in the fire, and I pull it out
and weld.  (Then I reflux and repeat at least once, often more.  I'm not
proud.)

Bruce
NJ

>>> [email protected] 07/30/03 12:09PM >>>
<large snip>
 As the day went
on, though, I had trouble getting him to "see" the difference between
welding heat and cooler heats- any suggestions? For some reason, every heat,
he wanted to pull it out cooler and cooler. Ekk suggested that he not look
at/into the fire quite so much, and that helped some, but any advice you
guys have would help.

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