On Tue, 30 Dec 2003 19:11:33 -0500, "mongke" wrote:

On Wed, 31 Dec 2003 03:02:58 +0000, Loren Coe wrote:

In article , mongke wrote:
On Wed, 31 Dec 2003 01:51:00 +0000, Loren Coe wrote:

In article , mongke wrote:
Thanks in advance for the input

4. Suppose I cut steel pieces with torch. If I want to weld/braze them
along the cutting lines, do the cut pieces need to receive some treatment
prior to the welding? Happy New Year everybody, BTW Mongke

if the cut is "proper", ie, clean and w/o slag, it is ready to weld.
for brazing? i dunno, probably need to brush or grind it, get it all
bright. good luck, --Loren

But what about temper? If the metal gets so hot when cutting, wouldn't it
affect the strenght in the area just along the cut? Mongke

if you are truly a newbie, not using exotic metals, welding mild steel,
stop worrying. tempering is something to worry about later, and it
is done after welding is completed. --Loren

O.K.

Happy New Year!

Mongke

Adding to Lorens comments:-
The heat required for brazing is enough to affect the temper of almost any
steel (even HSS if you aren't careful, ask how I found out!).

If you wanted to braze pieces that you had cut with an oxy-acetylene torch,
you would almost certainly have to grind or file them to get the edges clean
and flat enough to get a good brazed joint (about 0.005" max gap). You would
probably want to clean them up with an angle grinder before gas welding as
well.

Have fun

Mark Rand
RTFM