.030" Wire, 3.54 mm Steel, PICS, Questions.

[vanagon nut]

Hi all.

I might be at the limits of my Hobart Handler. Guide on lid doesn't specify beyond 1/8" steel using gas shield. By my measure, steel is a *hair* thicker than 1/8".

Am running a dedicated #12 wire 20 Amp breaker to MIG, clean ground clamp to work, Tri-mix, Hobart "Handler" 140, .030" wire.

Pretty sure that: tip angle correct, pretty close to work.

Slowing wire speed down allowed me to make a slower weave in hopes of best penetration. Is the bead in lower and RH or image too "proud" (high)?

Would going to .035" wire, lower wire speed, achieve deeper penetration? (pass more current?)

Or, do signs of heat on backside of work indicate penetration OK?

I am hesitant to start over (again) on this piece so may weld backside where I can.

Thanks for any pointers,

Neil.

 

[keith19]

0.035 wire would be putting more heat into the weld, and you'd be moving more slowly, so that's good too.
But don't weave too much, or this will cool the weld a bit. Also use short runs, pausing between for a few seconds, because on 0.035 your machine will be making more heat, and may reach its cut-out limit quicker.

The backside as shown needs a seam running too; the penetration is poor.

 

[vanagon nut]

Thanks Keith19. Your candid assessment is most welcome.

I'll grind down welds, redo, weld front and back. This is an engine mount bracket and will end up being overbuilt, but that's a good thing, as are better welds.

I knew I'd gotten better penetration on other work I'd done with this thickness steel. It may simply be that I had used .035" wire at that time.

Not a great image, but shows signs of better penetration.

http://sites.google.com/site/tubaneil2/_/rsrc/1255697477496/SupportPSweldback-medium-init-.jpg

Though this part was somewhat overbuilt, (engine carrier) and penetration is not as good as it could've been, it did not fail. This spawns at least a little confidence in this amateur as I'll be building a new carrier.

Thanks again,

Neil.

 

[keith19]

I see you're a busy guy, Neil. Lots of interesting mods there on your pages...

 

[vanagon nut]

Thanks! Yes! Lots of time spent on my Westy. Have learned a lot working on it.

This forum really helped with welding tips towards fabricating certain parts for the engine swap. Kudos to you all.

The "Starship Enterprise":

https://lh4.googleusercontent.com/-...fk/9qfhfvIsVMU/s800/StarShip%20Enterprise.jpg

is out and will be replaced with a better designed carrier I"m working on. Work sees me away from home right now, but hope to get back at designing and building the new engine carrier soon.

 

[vanagon nut]

So for any of those curious....

Though these practice beads were on the flat, under same conditions, same material, used .035 wire, held gun a little more upright and closer to work, slowed down feed and weave. Seemed to help. Especially slowing down feed and weave.

With bead showing brown at start as #1, from RH to LH of images, tried progressively slower wire speeds. You can see how the speed was super slow on far LH bead. Penetration appears to be not as good as beads # 2, 3.


Neil.

 

[keith19]

Interesting stuff. I think you're reaching the limit in metal thickness for that Hobart. Nice machine though.
As you say, using thicker wire and slowing down helps some, but making the weave too wide on top loses heat into the steel, so doesn't penetrate as much downwards.

You are only laying beads on plate there, so don't expect full penetration. If making a butt joint with proper edge preparation you should be able to join 3.5 mm okay, taking it pretty slowly.

When a welder is at top settings, especially a hobby machine, it's getting the speed and technique just right that is important, because there's no machine settings left. This takes practice and experience.
Any machine has its limits, and we just have to do the best we can with whatever is available at the time.

 

[vanagon nut]

Interesting stuff. I think you're reaching the limit in metal thickness for that Hobart. Nice machine though.
.....

You are only laying beads on plate there, so don't expect full penetration. If making a butt joint with proper edge preparation you should be able to join 3.5 mm okay, taking it pretty slowly.

When a welder is at top settings, especially a hobby machine, it's getting the speed and technique just right that is important, because there's no machine settings left. .....

Thanks Keith. Good point on limits of a hobby machine. In hindsight, for the time taken to run a new circuit, I should have run 220 VAC and laid out a few more scheckles for more capable welder. Regardless, that welder has been reliable w/o any birds nests or such.

In this case, my skills are still lacking. I didn't prep the joint (grind) or leave a root gap. I imagine these would provide a chance at acceptable penetration. All good learning experiences. Once I'm done making v.2 or v.3 of this bracket, thus perfecting my "production" processes, I'll be able to start making these parts full time. Ha ha ha. Kidding.

Neil.

 

[backpurge]

Vanagon
I would try and not get into the habit of weaving, stringer beads are a far better option

 

[vanagon nut]

Thanks backpurge. I think I understand the "why" behind your suggestion. Stringer bead (narrower weave) keeps heat more "centered" thus deeper puddle?

I'll look into that and practice-up when I get home.

Neil.

 

[R Kraft]

Usually for better penetration you would want the wire speed fast,the torch angle vertical to the work,a short stickout, and maybe a narrow circular motion.
Preheating with a heatgun or torch will help too.
Robert