[70Chevelle]

Hello everyone,
I will be doing a bunch of production work (indoors) welding 3/4" steel plate to 1/2" rectangular tube, and I was wondering what is the best wire is - Solid or dual shield? What are the benefits of one vs the other? The machine I will be using is an XMT450MPa, and I believe the gas will be about 85/15 AR/CO2 mix.

Thank you,
-Anthony

[Shield Arc]

Personally I think dual shield is a little faster than Mig. But you’d have to look up the deposit rates to be sure. Dual shield is kind of a pain to clean up after.
I really love Lincoln’s L-56 Mig wire.
To me it would be a toss up, which one to go with. I wouldn’t use anything less than 1/16-inch wire in either case.

[Mike]

Welcome to the forum.

[70Chevelle]

Thanks guys!

I think they already went ahead and ordered some .045 solid, and some dual shield. I will try both, see what works best for us, then order the 1/16 of what we like. These parts will be painted once they cool, so the less cleaning the better.

-Anthony

[Otto Nobedder]

You will have higher deposition rates with dual-shield, every time. Faster production.

Yes, more clean-up. That's the balance you must measure.

Also, because of the amperages you'll be running with dual-shield, you will have more penetration. That's a factor to consider while developing a WPS.

This is definitely a "test and compare" situation.

Steve S

[Boomer63]

I have a fabricator out here that is using .045 hardwire. When they mentioned they were running .045 I assumed it was flux ... but it is hardwire, spray transfer, I think he told me it was a 90% gas mix. The CWI at the company explained that a lot of people were going in that direction, and getting away from flux core. Shoot, spray transfer is hot, hot, hot! The test for this company takes about four hours. It is a 15" long, closed root (1/4" root opening), in 2G. The top is 0 degree (90 degree) or no angle, the bottom plate is 45 degree angle, the iron is 3/4" thick. This company is all about production; they are all asses and elbows!

The CWI told me that only about one in 30 or so welders pass the test. Given the level of training available in this area, I believe it! But! I am trying to change that!

[Otto Nobedder]

Spray transfer is exceptionally difficult to use in any position other than 1G/1F, so I understand the low pass rate!

In my field, it's used on 304ss in 1G on vessels in rotators, with ceramic tape backing. I actually had to pass an x-ray on it on a sample piece as a demonstration to get our "R" stamp, even though I'll never use it in a repair (GTAW is specified for vessel repairs, short-circuit GMAW for ancillary structure).

I think I'd not want to work in a sweat shop like that... I've had my share of those in the past, and far prefer being allowed to take my time for the sake of quality.

Steve S

[Boomer63]

Spray transfer is exceptionally difficult to use in any position other than 1G/1F, so I understand the low pass rate!

In my field, it's used on 304ss in 1G on vessels in rotators, with ceramic tape backing. I actually had to pass an x-ray on it on a sample piece as a demonstration to get our "R" stamp, even though I'll never use it in a repair (GTAW is specified for vessel repairs, short-circuit GMAW for ancillary structure).

I think I'd not want to work in a sweat shop like that... I've had my share of those in the past, and far prefer being allowed to take my time for the sake of quality.

Steve S

Lots of places using spray in all positions; thinner metals, rotational, structural. I keep a couple of bottles in the shop so the crew can get some hands on with it before they venture out into the 'real world'.

There are so many TIG jobs in this area. The welders know a bit about the process, but not much more. Very basic fit/up or print reading skills. I would not recommend sending these guys off to the power plant to weld Inconel without a lot more training and education! Sigh! That is what I am trying to change in this region; the skill level of welders as a whole! But, that is bold talk for a one-eyed fat man!

[Otto Nobedder]

Lots of places using spray in all positions; thinner metals, rotational, structural. I keep a couple of bottles in the shop so the crew can get some hands on with it before they venture out into the 'real world'.

There are so many TIG jobs in this area. The welders know a bit about the process, but not much more. Very basic fit/up or print reading skills. I would not recommend sending these guys off to the power plant to weld Inconel without a lot more training and education! Sigh! That is what I am trying to change in this region; the skill level of welders as a whole! But, that is bold talk for a one-eyed fat man!

I suppose I should qualify that... Dual-shield is spray-arc and can be done in all positions (with practice). I've done more of it than I care to think about.

I was referring to solid-wire spray arc, which I was recently introduced to, with the "1G/1F" restriction.

Steve S

[rake]

Steve, at the shipyard we did a lot of 2G in spray transfer both .045" and 1/16" wire.
Also a lot of 2F. In certain applications we did 2F spray twin arc with a guy on each side.
The lead guy would start the root and get about 2"-3" closed and the lag guy would light up
and "chase him" all the way to the end of the joint! Seen a lot of UT test results and the stuff
was surprisingly clean.

Pulse spray is a whole lot more flexible and still allows for a high deposit rate.

[Rick_H]

I use solid wire spray with .045" wire, 98/2 gas on a Millermatic 252. I've been playing with other positions but like Steve mentioned, 1F and 2F is all I've done so far with what I am happy with penetration and cosmetic. Vertical has been tough with out dripping, although Im getting closer.

I'm welding 1/2" A500 plate to 3/8" wall A500 rectangle tubing, single bevel 30° on the tubing. ER70S-6 wire, per the print.