Hobart 190 + Spool Gun = Aluminum!

[bplayer405]

Got all my ducks in a row; got the welder I've been after for years, spool gun, 100% argon - 2 small tanks, spools of wire, ss brushes, scrap material, ... finally nothing in my way. It was time to stop watching videos about everyone else welding aluminum and do it myself.

It took a bit find and to get use to the sound and the feel; it is quite different than welding steel. First weld was actually a weld, tall and ropey, but a continuous bead. A little more heat, better. Kept playing around for about half an hour and yes, I can do it too.

I definitely need practice. I'll definitely put in the time on all the joints I'll need to weld and get them as solid as I can. I have a opportunity to get a new-to-me Polar Kraft jon that'll need a floor conversion from a V to flat and decks framed and built. I get to that project I'll definitely post pics.

First time welding aluminum! Welds 1 through 4 then best and some joints...
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[pull-do]

Looks good to me

 

[bplayer405]

Wish my added pics would post...

 

[bplayer405]

Anyways... need practice...

 

[pull-do]

That looks to be to cold on your settings

 

[bplayer405]

Starts cold, ends hot, hopefully the middle wets out, I'll be needing joint practice for sure.

 

[Yomax4]

On the thicker materials it never hurts to hit it with a little propane or Oxy Acet to warm it up prior to welding. Because it starts cold and ends hot you can try starting in the middle and work outward. Helps sometimes.

 

[bplayer405]

This is all 1/8" stuff and thinner. .035 4043 wire welding 6061 material. Getting the spray to go where i want it to is my main focus now. I believe technique will take care of it, once I get it down. Definitely different from steel. I have some .030 5356 wire to try next. It will be my main wire for welding boat alloys. Time in the practice chair should make it all good.

 

[bplayer405]

On the thicker materials it never hurts to hit it with a little propane or Oxy Acet to warm it up prior to welding. Because it starts cold and ends hot you can try starting in the middle and work outward. Helps sometimes.

Since the heat moves forward 4 times faster than with steel, I burned through the end of the thinner material in the first pic. Then tried stopping short of the end and started again at the end coming back to the end of the first weld in the second pic. Seemed to work ok. Maybe a full tack at both ends would add enough material to help keep burn through at bay... probably lots of ways to do it though.

 

[bplayer405]

Tried the .030 5356 wire tonight. Started out too hot. Was able to dial it in by lowering voltage and upping the wire speed. Tried a joint and it was a bit cold. A minor adjustment and the other side went way better. Had a hole in the corner and was able to fill it easily with this wire. Its a bit easier to weld with than 4043. A bit more smokey at 30cf/h. Is that normal?

 

[bplayer405]

Finding out that the door chart isn't that good at initial settings for aluminum. Still playing with the settings, but getting them down fairly well. Kept layering welds to flow in the cold welds in the second pic. This is 1" square .0625 material.

 

[Gary Fowler]

Your first photos show lots of black "smoke" after welding, a sure sign that the metal was not cleaned properly. Get a new stainless steel wire brush, dont use it on anything else. Brush well just before welding, wipe down with acetone to remove any oily residue.
Pre-heating will do wonders for the weld. After preheating, you can crank back on the voltage. Also dont try to make it look like a TIG weld, just stay in the puddle rather than stepping.
Keep practicing, you are getting better.
All the problems you are having is why I prefer TIG welding of aluminum and using a remote control to adjust the power. Crank it up to get preheated then back off as the aluminum heats up.

Really the only experience I have with a spool gun was when I was in the army (I was division welder-3rd Armored Cavalry) welding up broken personnel carriers which are all aluminum. It took a lot of preheat on those because nothing was thin on an armored vehicle.

 

[bplayer405]

"Also dont try to make it look like a TIG weld, just stay in the puddle rather than stepping."

I'm learning that this is important. I did a search on YouTube for welding thick metal to thin (steel) as I just setup my first paying gig welding hinges back on a trailer door and found a video where Jody from welding tips and tricks was messing around with wire feed speed vs penetration. He cut and etched welds from recommended wire feed for material vs half speed (mig like tig looking welds) and showed way better penetration on the recommended wire feed welds. The "mig like tig welds" showed some incomplete fusion down to the root.

So, since I've seen what can happen, I'll be focusing on proper fusion and making my welds hold instead of making them look like art.

 

[Gary Fowler]

The secret to making uniformly good welds is getting your preheat just right. Too cold and it will be lumpy and not fused at the first few inches. Too hot and it will burn thru on you. Since aluminum doesnt change color as it gets hotter, a good infrared temp gun is a good investment. I plan to pick up one for myself next time HF has one on sale. Temp sticks are ok, but you need so many different temperatures that they can get expensive.

 

[bplayer405]

The secret to making uniformly good welds is getting your preheat just right. Too cold and it will be lumpy and not fused at the first few inches. Too hot and it will burn thru on you. Since aluminum doesnt change color as it gets hotter, a good infrared temp gun is a good investment. I plan to pick up one for myself next time HF has one on sale. Temp sticks are ok, but you need so many different temperatures that they can get expensive.

I recently bought a used jon boat that I'll be modifying structurally. Mainly adding side ribs from taking out 1/4 seats in the mid section. I have to figure out how I'll be bending the material from the seats to make the supports first, but I plan on riveting the supports to the side of the boat then welding them to the existing floor ribs. Material is .072 5xxx series aluminum. I do plan to preheat before welding. I'm gonna try a heat gun first to preheat and pick up a infrared sensor like you plan to see what temp works best on scrap. Definitely don't want to mess up my new boat!