On Sun, 3 Feb 2019 08:49:59 -0700
"Bob La Londe" wrote:
I know. I know. That's not really a thing. Still I was welding up some
T-handles on thread rod for some tools yesterday. I noticed that for just a
fraction of a second at the beginning of the first weld on a part the weld
would be unstable and throw a little spatter. Then it would stabilize and
weld perfectly. All I can attribute it to is that it took a tiny fraction
of a second for gas to reach the nozzle. Still if the gas solenoid was
triggered half a second before the wire was electrified I can't help but
think the start would be better. When I shut the welder off I happened to
notice my CFH gage was showing a little under 20, and the welder recommends
30 for everything on the flip chart. The other day welding hinges on some
thin wall rectangular tube 20 seemed to be fine. Maybe it was just the
shape of the t-bolt? Maybe the 30CFH setting hits the nozzle quicker? I
have the regulator style flow gages.
P.S. Referring back to my issues with this welder and the bad gas
diffuses... I use MIG welding as the fast fall back tool for a lot of
things I'd often find other means for in the past. Even my crappy welds
look better. I haven't used my little flux core only machine since,
although I still would outdoors.
Higher flow rates can cause turbulence and possible bad coverage. When
I was doing a lot of welding for my Dad on a couple products. I would
run 8 CFH with 75/25 gas. No reason to run 30 when 8 would make
perfectly good welds. My favorite nozzle is slightly reduced/tapered at
the tip. Looks a lot like this:
https://www.amazon.com/dp/B072WDVJJ6/
I couldn't get away with running 8 using big stove pipe nozzles
though. Never needed one that large unless trying to weld 3/8 in a
single pass which has its own set of problems...
Lighting up, starting out is always troublesome. You might want to try
lighting up a 1/4 to 1/2 inch from where you want to start and then
rapidly back up to that point once your arc is established. Picked this
tip up from watching Jody's videos and works well. Providing I remember
to do it, don't weld that often anymore...
--
Leon Fisk
Grand Rapids MI