PDA

View Full Version : arc welding question


vslayer
07-06-08, 04:01 PM
if im welding a thin sheet of metal, do i want to turn the amps down and move slowly or turn them up and move quickly? so far ive only succeeded in melting holes in it.

draqon
07-06-08, 04:11 PM
horray for plasma welding

cosmictraveler
07-06-08, 04:34 PM
You should to learn how to weld first.

http://www.efunda.com/processes/metal_processing/welding.cfm

vslayer
07-06-08, 09:01 PM
i know enough about welding, but its usually on large farm machinery, as opposed to my car door.

kevinalm
07-06-08, 10:42 PM
Lower the amps and use a smaller diameter rod. Stainless if the expense isn't a problem, it seems to work better. Industrially, "mig" welders are used, basically an inert gas imersion wire welder.

vslayer
07-07-08, 12:22 AM
thanks, ill give that a go.

cosmictraveler
07-07-08, 10:21 AM
What type of Arc welder do you have? What type of electrodes do you use? Every type of metal needs certain electrode rods to use with them. Just using a lower setting doesn't always work.

(Q)
07-07-08, 12:11 PM
if im welding a thin sheet of metal, do i want to turn the amps down and move slowly or turn them up and move quickly? so far ive only succeeded in melting holes in it.

Usually, you would use Oxygen/Acetylene instead of Arc welding for thin sheets.

iceaura
07-07-08, 01:03 PM
Usually, you would use Oxygen/Acetylene instead of Arc welding for thin sheets. I've seen that, and tried it myself with little success - it isn't easy, but it works if you can do it.

Low flame, careful setup (get it horizontal or at least not too difficult an angle) constant "dancing" motion over a fairly wide area, practice on scrap. Good luck.

cosmictraveler
07-07-08, 10:39 PM
I'd rather use Mig with thin metal.

vslayer
07-08-08, 12:54 AM
well, ive found a sort of tack and go method with extremely low amps seems have worked.

cosmictraveler
07-08-08, 10:06 AM
To low and slow and it will stick.

(Q)
07-08-08, 11:39 AM
I've seen that, and tried it myself with little success - it isn't easy, but it works if you can do it.

Low flame, careful setup (get it horizontal or at least not too difficult an angle) constant "dancing" motion over a fairly wide area, practice on scrap. Good luck.

I would agree that welding with O/A requires practice, but will give a more solid weld to thin sheets of metal than Arc, which can easily melt portions of thin sheets and destroy the project.

cosmictraveler
07-08-08, 12:25 PM
Fundamentally Speaking
MIG is one of the easiest processes to learn. Most people can learn to run good beads with MIG in just a few hours. Now don't get me wrong here. Remember, I am all about the basics in my articles. The keep-it-simple-stupid theory is my style. There is a lot more to MIG welding than just learning to run beads, but in this article, I'm talking fundamentals.

When did MIG start? MIG came about during World War II. It was developed to help produce weapons and equipment faster. It was then used in the postwar booming economy, mostly in shops and factories.

What is MIG? MIG stands for metal inert gas. In stick welding the flux on the electrode melts and forms a gas to shield the puddle from the atmosphere. The atmosphere has hydrogen, nitrogen, oxygen, and other gases that will cause weld defects if allowed to get into the weld pool.

In MIG, a spool of solid-steel wire is fed from the machine, through a liner, then out of a contact tip in the MIG gun. The contact tip is hot, or electrically charged, when the trigger is pulled and melts the wire for the weld puddle. This is accomplished in several ways. This article discusses short-circuit welding.

http://www.thefabricator.com/ArcWelding/ArcWelding_Article.cfm?ID=929

thecollage
07-08-08, 01:21 PM
turn them down. you get burnouts and gasouts if you try to weld too hot and move too fast on thin sheets of metal.

such a fine trade that is.