Weld strength with flux wire vs gas....

[ATP]

Is there a difference in weld strength between the two with all other things being equal....?
thanks for responses...

[Shield Arc]

There are so many wires on the market today, that run on different processes.
You have to read the manufactures specifications. Strength is one thing, deposit rate is another.
I've always thought dual shield, (flux core gas coverage) was very fast for all position work. For most of us here dealing with just mild steel, just about any wire or process will have plenty of strength.
I think where most people get into trouble with wire feeders, is they do not run them hot enough! It is so easy with a Mig welder to get a beautiful looking weld, and yet have no penetration! Mig welders are notorious for cold lap, I'd much rather see a little under cut on the toes of a Mig weld than cold lap! At least then I know the weld has bitten into the base metal.

[weldermike]

There are so many wires on the market today, that run on different processes.
You have to read the manufactures specifications. Strength is one thing, deposit rate is another.
I've always thought dual shield, (flux core gas coverage) was very fast for all position work. For most of us here dealing with just mild steel, just about any wire or process will have plenty of strength.
I think where most people get into trouble with wire feeders, is they do not run them hot enough! It is so easy with a Mig welder to get a beautiful looking weld, and yet have no penetration! Mig welders are notorious for cold lap, I'd much rather see a little under cut on the toes of a Mig weld than cold lap! At least then I know the weld has bitten into the base metal.

Very well put, I see it all the time.

[CHDinCT]

Mig welders are notorious for cold lap, I'd much rather see a little under cut on the toes of a Mig weld than cold lap! At least then I know the weld has bitten into the base metal.

What is cold lap and how would I identify it? Any pic's? When you say this is common with Mig welders, do you mean when using gas (vs flux core) or more generally as applying to flux core too? Just learning to use my Mig/flux core and planning on a major project come spring. Thanks.

[radioman]

I am not an expert or anything - still learning myself and I might be corrected by other experts. basically put- you really want to have a good penetration. If the flux metal you are feeding is not reaching through the metal you are welding - then its not hot enough or its too thick for what you are doing.
A cold lap is basically a bead on top of two metals and it not melting both sides of the metals you are joining. You can almost whack it off with a hammer and chisel. Sometimes you cant whack it off - but its only holding a little of the metal pieces you are joining so it breaks off under stress.
Did you try practicing welding yet with scrap? If so then cut across the welded pieces in several places and look at how its melted together. Be sure you cut across funny looking welds and good welded piece to understand your technique that needs to be modified.

[Shield Arc]

Replace "overlap" in this picture with cold lap.

[Gary Fowler]

Another type of cold lap can be found between passes and is a common MIG /FCAW occurrence where the two passes don't fuse together and just basically lay on top of each other with very little fusion between the layers. This may occur and not show side cold lap and is hard to see even with xray unless you can expose it from the sides which is not common practice or even possible in many cases. For this reason, many welding engineers dislike the use of it in pressure containing welds unless it is in "spray mode" which runs with very high current.
Always run your wire feeders as "hot" as possible.

[Shield Arc]

Now here is a hot Mig weld! .035" Lincoln L-56 wire.

[Gary Fowler]

Now here is a hot Mig weld! .035" Lincoln L-56 wire.

Now that is the way a wire weld is supposed to look

[radioman]

nice weld -- I cant do that ... yet . I hope to do that good before I die.