Weld seam after machining

[Smokedaddy]

Pine Arizona ...

[cliff69]

;-0 little farther away..nice house though.

[G.A. Ewen]

<font face="Verdana, Arial" size="2">Originally posted by torker:
Now GA...We expect, in the future...that you constantly warn us that....mild steel can shatter like glass
Russ</font>

Russ, did you see my last post on the subject? No responce yet

[torker]

I'm lookin!

[gunsmith]

Yup your right. Too fast and not waiting long enough for the mig wire to fill in. That's the trouble with trying to make a buck.I am using a roller to rotate with some improvement, but not enough. I'll give that pre heat and slow down a try tomorrow. It would be nice to have a uniform finish from end to end without having to weld end to end. Technique has to be improved.

[Smokedaddy]

Gunsmith,

Next time try a couple of things. After setting your heat, but while welding, have someone adjust your wire feed. The wire feed should be adjusted until it sounds like bacon frying but a "extremely smooth crackling sound". There are a number of different techniques we could discuss but give this a shot.

For positioning yourself, use two hands for steadiness, or even putting the nozzle between your two fingers if necessary and actually lightly putting the nozzle on the material being welded. Make sure the liner (welding cable) isn’t working against you. It shouldn’t be pushing your gun or putting YOU in a bind whatsoever. Try making really small circles, like 3/32” circles, and advancing away from the puddle every revolution of the circle. Just as a guide, I’d try making a circle every second. Keep a consistent arc gap too. If you practice this on some scrap plate, you’ll see how the weld flattens out considerably and no undercut. I now it sounds like a lot work physical work, but if you give it a shot and experiment, you’ll like the results.

-SD:

[This message has been edited by Smokedaddy (edited 01-25-2005).]

[gunsmith]

Smokedaddy: Never thought of using full circles of any size. In all cases I weld with a half circle back lapping over its self. I gotta try that full circle. I have the feed on the mig down pat but the heat might be a bit too high.Thanks

[torker]

gunsmith..if you are using a roller be careful where you are welding. If you split the circle into a clock and stand on the "afternoon" side, you should hold your nozzle somewhere between 12:30 and 1:30 as the shaft is rolling. I prefer to have the shaft roll away from me....this is like "pulling" a weld. You can see the puddle really well. If you are holding the nozzle at say 3:00 or worse (4:00) this can also cause undercut. If you can, build a small rest to lay your gun on while welding. The beauty of using the positions I mentioned is when you need to resart (if rolling manually)you are bang on the lip of the end of where you stopped. Makes for very pretty restarts. There is an old guy here who's been building driveshafts for 30 years. He uses two dual wheel rollers and welds them non stop with 7018. It's very hard to see start/end. He wears a leather sleeve and starts the roll with his hand and ends up near his elbow. Pretty slick. I've tried it but usually get a slip somewhere.
Russ

[Elninio]

can you post some pictures?

[Thrud]

Your technique is faulty if you are getting undercuts on the weld -for critical parts never use arc welding - TIG is better and less stressful to the metal - plus it will machine smoothly - arc welds never really do.