Tips For MIG Welding Aluminum Lap Joints With A Spool Gun

Here's some tips on how to MIG weld aluminum lap joints with a spool gun!
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[@brandonb5298]

So far the best video on spool gun I’ve seen yet

[@jedediahbc]

You said it wasn't one of the prettiest welds, well for aluminum mig I thought it was fantastic. Your to modest it was great!

[@dmmdmm5435]

you are right about the time saving aspect of mig vs tig. not having the "luxury " of time, in a production shop is what it all boils down to. pretty, time consuming tig welds with very little post -cleanup have their place. less pre-heat concerns with mig, on thick sections. when building a pontoon boat, you'll meet your deadline quicker with mig. small jobs sometimes go quicker with tig. there is a balance to be found, which only experience and the advice of other knowledgeable fabricators can make it all come together in a timely fashion. learning by mistakes and success is a hallmark of our profession.

[@jessiecasteel5090]

Excellent video, very informative, good illustration, no wasted time, no drama!

[@gordjohnson70]

Luv your videos. I find them very informative. I'm retired now, but I welded in a production factory for years, but never really got much training. Went in knowing nothing, got 10 mins. training, then got put to work on a production job. I just started reading welding manuals and learned a bit from the other guys. Like a lot of welders, I never did get any welding certificates or did any tests. Like you said... cracks often start at the end of the weld where a shallow scoop out is sometimes left. Your method of pulling back and back filling a bit is very good. I do that too. However in some situations (like thin sheet metal ), I find 2 welds work better. Weld in 1/2 way from both ends and join the welds in the middle. In a stress area, I'll sometimes even put a short support weld on the back edge and wrap the corner. A little extra support at a stress point never hurts. Thnx again for you great videos. Ps... I'm thinking about buying a small portable 120 / 220 stick welder for a few retirement projects (steel framed picnic tables etc. ). I know a lot of the small welders are junk, but the AHP arc 160 st looks like it might be pretty good for what I need. It gets good reviews, but I've never seen one. I'm looking for a good quality unit that will burn a 3/32 7018 rod on 120 a household current. Price is not a big concern. I just want a good one. Any suggestions ? Thnx again, Gord [e-mail]

[@benchleebanawag8451]

your welding techniques are great,so effective sir

[@turbocobra]

Thanks for the video.. I always tig weld aluminum on my channel, I have spool guns that came with 2 of my welders but i have never used either, i need to give them a try!

[@fredsmith6160]

I bought a spool gun when I first bought my everlast mig welder and I gotta admit I haven't use it yet either but hopefully will use it next spring on some jobs.

[@MichaelSmith-bc3it]

You have a good approach to teaching. Thank you.

[@brentsmith5647]

Brilliant man 👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍

[@BMWDCK75]

Great video and yes more mig welding aluminum video's.

[@isaacharrison4990]

Great video Bob, please make more like this. Helped me a lot with Alluminum.

[@natanshvarts31]

Good information for me, thank you very much. Please more on Aluminum.

[@robertblackshear8963]

You're too good to make a bad weld. Awsome.

[@carlosextromolo3753]

I want to get a mig gun for my everlast mig welder. Being able to weld aluminum would be awesome.

[@alexhernandez0003]

You are the best ,this is what’s happen wen you know alat

[@johneisele6264]

I learned a ton from this video. This was awesome. I hope to see more

[@tonybaumgartner6014]

Thank you for another great video. You present the information in such an easy way to understand and every word you say is useful and I can apply it right away to my welding.

[@jfpinkston1]

An etch and polish would have been interesting for comparison. Thanks for the video!

[@lancerudy9934]

Great video 😊 THANKS.

[@davesmith8053]

Thanks I tried it today my beads look ok but not like yours. I have a Miller 252 /30a spool gun. I have been practicing as much as I can. I'm bust all summer with work. I helped out friend that built boats in my 20s when off in winter fitting boats but never did the welding noe I'm working on the welding. Not a lot of vidios on aluminum. I'm running .035 wire. Seam to be good. At 23.5 amps on 1/4 plate wire at 670-720 is so fare mt best work Thanks Dave

[@MrAlexfoods]

appreciated, a very educational video. top shelf .

[@jamesboswellii]

Great instruction! Thank you!!

[@georgedreisch2662]

Would be interested in any experience / advice you could pass on or share regarding 356 cast aluminum with a spool gun. Wire recommendation?

[@elijahjohnson1184]

I'm thinking about buying that Everlast welder that Bob demonstrated in a few of his videos. Looks like I should put a spool gun on the shopping list as well.

[@Welddotcom]

Check out the new Weld.com store before buying anything. We'll match prices and are currently offering discounts on the entire store using promo code CONSTRUCTION.

[@lsellclumanetsolarenergyll5071]

Excellent. Now you did use a Spool Gun but can you explain a bit on MIG welding Spool or not doesn't matter what issues can occur like wire burn's back to the tip and like what difference the Argon Flow would make. Thank you

[@martinzsoltviczina8362]

Hello I have Iweld double pulse MIG welder, and I got stuck with the setting. We used synergic MIG welder before and we wanted to change for dual pulse since you can make way better work with it, but I can't even find any settings that works for us. The problems: The wire is literally dissapear most of the time when I start to weld and I see something like fire. (As I could see there is not setting for wire speed, I could only turn the wire speed with amper) And there are still the black spot

[@johnmacmillan627]

Thx Bob! It sounded like you were in spray mode. Is it possible to achieve spray mode with a lower voltage say for welding 1/8 to 3/16 aluminum?

[@jamesjohnson7266]

looks good very useful tips thanks again

[@bestintheindustry]

good explanation

[@davidspin581]

Try 5356 in a spool gun, I run .364/.046. Almost never birds nest, plus it's stronger.

[@7weld7]

I would have dropped the voltage a bit and adjusted the push angle a bit heavier For 1/4" I've had lots of success doing steps from centre of my arc to the leading edge of the puddle and holding 1-2jump1-2jump (*note those are rapid 1-2 counts not anywhere nearly as long as Mississippi's haha) by doing so you find the sweet spot for speed and can then run that pace at 1/2 speed without steps just fluid motion, this welder appeared to be using a 3 steps forward 2 steps back waving back and forth slight push technique which sets his travel speed. (Everyone's is slightly different and everyone runs slightly different parameters, no 2 welders are the same✌️. you shouldn't be way out of the range of parameters or angle ranges and push for more penetration pull for less but 99% of the time you'll be pushing). Practice stringers much more than weaves. Thin guage? ( around 1/8 and below) Keep your work elevated off the table to have less heat dissipation into the work table below and a better more even weld with a more stable arc that goes where you want it to. ! Happy welding lads. Any questions just post a reply I'll answer when I have time.

[@londohondo]

What gas can be used if Argon is not available?

[@joselomeli2678]

Hi, what's the best multi welder for you esab 285 or esab 235 ? Thank you

[@brianm2152]

I would have liked to see that unclean weld cut open. Do you not have to use a SS brush to remove the oxide layer when MIG welding like you do on TIG?

[@pescettoloco]

Thanks for the video

[@rileydavis1447]

What kind of helmet are you using, sir?

[@billarroo1]

Well Bob that weld looks great to me !!! one question, is can you show 3g, 3f, and 4g, 4f, MIG ALUMINUM !!! out of position, I had to weld an aluminum 53ft flatbed trailer that had a crack through the side of the flatbed rail, 1/2" thick, NEED SOME HELP !!THANKS, WILLIAM

[@10000rambos]

I have a question; when I TIG aluminium, (which is my favorite process/metal, by far) I use travel speed, the foot pedal and how much filler I'm feeding, to control the puddle size and the heat; beside travel speed, MIG doesn't allow for that kind of control. With all that heat in metal, I don't understand how the bead doesn't completely wet out by the end of the part, . Is it the wire feed speed that allows the filler not to wet out into a huge puddle? Thanks, great video.

[@quinnstrohl97]

I have had puddles wet out when running long beads with a spool gun. Usually I try to limit myself to 6 inch welds.

[@lenjohnson4574]

quinn strohl . on flat? or vertical welds?

[@bma56]

Bonjour pourriez-vous faire un essai sur l’alu de 2 mm d’épaisseur

[@straightouttamarysville7749]

What Heat do you use for 1/8” aluminum and what’s the wire speed and Volts?

[@loganironside343]

If you run regular mig wire through a spool gun..and then run aluminum filler wire will it get contaminated???

[@gramps717]

in the video at 4:00 the machine indicates 22.5 V for volt is equal to about 121 A for amps is this right?

[@Bigboodydoop19]

Try spray arcing

[@codybhughes1]

How is it going bob? You should have seen the smile on my face when seen you pop up on this video! Weld on brother! #exstudent ~2015 Cody H

[@markvietti]

nice.. was worth getting flash burn .....thx

[@unioniw111]

Hi Bob, I’m looking for some tips on welding thin gauge (16) aluminum with a spool gun. I know it’s not ideal, but it is what I have to work with at the moment. I’m looking to fix some areas on the chines/ keel of an old Jon boat. My plan is to clean, clean, clean, and then I will be fitting sections of 1/8” angle aluminum over the bad spots in the keel followed by seal welding. My thought is to concentrate my pool more towards the thicker metal. Any tips on preheating or anything you could think of would be great! I’m thinking .030 wire with a .035 tip. Your videos are awesome! Incredibly helpful coming from a 15 year union Ironworker

[@eugenecosentino392]

Nice welds as always Bob. What happened to the old pipeliner hood? Strange to see you welding with anything else lol

[@tomherd4179]

If one has a TIG welder (AC hi-freq) why would one need a spool MIG set up? I am only asking for self learning/information, not trying to imply anything more that that. The only reason I could think of might be the speed of doing a weld project, or perhaps the thickness of base metals involved? Thanks for the great videos.

[@Welddotcom]

In regards to this machine, the TIG mode is DC only, so MIG is the only process you can do Aluminum on.

[@Countryboy2206]

Mig is faster so for production it will be used over ac tig, depending on the size of aluminum.

[@tomherd4179]

Thanks for the direct answer :-)

[@randyharris1991]

For the machine you used did you program it to your wire size? Im wondering if you bumped it up a couple wire sizes it would allow you to have more perameters to choose from? With my experience running a spool gun or push pull using 3/64 5356 welding 1/4" ive always ran it in hot ranging between 450-500 wfs and 24.6-25 volts with either equipment making a fillet weld... i understand youre only using .030 and its limited however having options is also nice. Also i am impressed on how it cleaned on the "dirty side" of your work piece, i was expecting porosity everywhere; do you think you could do a demo on alum that was previously covered in grease and other oily grime, with only a good wipe down and minor grinding prep?

[@lv6fomor]

huh so that's what aluminum mig'd looks like, reminds me of tig dimes a little

[@briangillespie4160]

What wire were you using? 4043?

[@DavidFinchMMC]

Good video, way to use a brush that says it has been used on steel. Nice welding though.

[@DavidFinchMMC]

It is written on the handle of the brush with black marker. Normally that indicates that it had mild steel bristles or has been used on mild steel, both to indicate that it should not be used in materials with cleanliness requirements.

[@blairwise3339]

David Finch have you considered the possibility that he was labeling that brush as being a stainless steel brush. Maybe that's why it says S Steel.

[@DavidFinchMMC]

Where are you seeing the "S" before "Steel"? Believe me I get it, I make similar videos, and am not perfect by no means. My comment was snarky, but should be thought of as instruction to others reading the comment that it is not good to cross contaminate.

[@davesmith8053]

Are you doing any movement C, or circle , or whip ? Beads ripples look super even? ThanksDave

[@Welddotcom]

Just a slight whipping motion.

[@drob2793]

Can anyone help me find a video on uphill aluminum spoil gun

[@mrgreenswelding2853]

i want to mig weld aluminium without a spool gun, what is the preferred size to use that won't cause me problems? i will be running 5356 to build a boat.

[@chrisjones6165]

Mr. green need a push/pull gun then

[@mrgreenswelding2853]

chris jones nope i bought a mig now and run 1.2mm 5356 no problem. nothing special, but the aluminium set up.

[@nicko4071]

My millermatic has been running 5356 without a spool gun. Seems to work fine. Using a size up tip

[@chrisjones6165]

why not over 23 volts, aluminum is spray and isn't 23 volts needed for spray transfer

[@wrav47]

do you have to weld aluminum with straight argon gas?

[@mrgreenswelding2853]

yes and no. you can have helium in it if you are doing thicker materials. carbon dioxide is an active gas not an inert gas and will cause problems.

[@patw52pb1]

No. The shielding gas is usually 100% Argon or Helium or Argon-Helium mix, there are other mixtures, but are not widely used in general fabrication/welding. 100% Argon is probably the most widely used gas with Aluminum. The gas(es) to use is/are usually determined by the particular application or engineers specification, materials, material thickness, filler selection and process. Sometimes if the gas is not specified a shop will use what they have available and works. Carbon Dioxide (CO2) or gas mixes with a CO2 component are typically not used with Aluminum.

[@MrDidgy]

yes.

[@hvs2773]

Is that a Rebel 211 or 235?

[@Welddotcom]

215

[@tomasjonsson3064]

Where does the sot come from? If you weld aluminum with straight argon gas, there is no carbon present.

[@Welddotcom]

The black soot is magnesium oxide. When magnesium is vaporized by the arc’s heat and comes in contact with oxides, black soot forms. A proper gun push angle of approximately 15 degrees helps keep gas coverage at the leading edge of the weld pool, which reduces soot. Clean the base material with a stainless steel wire brush, and use the correct weld parameters for the wire size to minimize overheating of the weld puddle.

[@MrDidgy]

soot is typical of an aluminium weld using the MIG process, not sure why.

[@mrod4864]

Are you whipping in any way or just pausing??

[@TheJesusno2]

Mig welding aluminum just sucks sometimes. I do agree that the push angle technique is key, BUT alot of times you cannot push that's why it starts to get real weird welding into tight corners or having to drag out of a joint it become soot city!

[@markstevansen542]

gas coverage is key. I put some scotchbrite in the nozzle of my everlast spool gun to help diffuse the gas flow and even out the turbulence. It seems to help a bit with extending the coverage.

[@IcarusX72]

Like TIG, is it preferred to have AC on MIG aluminum?

[@leonardpearlman4017]

No. If you recall the "Cleaning" part of the TIG cycle? The electrode gets hot, the work is cleaned a little (oxides come off, you get a sandblasted look near the weld), MIG is only that. DC electrode positive all the time. LOTS of "cleaning" action. doesn't the electrode wire get hot? Sure, it does! It melts and is thrown on to the work. So, it's hard to TIG with DC + polarity b/c too much heat goes into the tungsten and it gets so hot, very inefficient. MIG DC+ is fine, because the hot electrode goes on to the work and it's just more heat transfer.

[@gamjam3915]

💐

[@jakobabbott5084]

um did that brush say steel ,.. your not suposed to do that

[@jakobabbott5084]

allways use aluminum only gear buy stuff just for aluminum your helmet and jacket are fine but switch everything out to avoid any cross contamination it could leed to porosity problems in aluminum