MIG welding aluminum tubing

[Whillyjo]

I am wanting to MIG weld a camper frame out of 6063 aluminum tubing (1”x1”, 1.5”x1.5”, 1.5”x2”, and 2”x4.5”). The tubing would be 1/8” wall thickness. I was planning on using a Lincoln 180 Easy MIG with a spool gun and 100% argon gas; I’m still working out what filler wire I need. But after talking to a welder my dad knows, he was very skeptical on whether or not it would work. He was afraid that I would burn through the tubing and not properly seal the tubing with my welds. He said the way to do it was TIG. I have MIG welded a little bit before (only steel though) but have never TIG welded nor do I have access to the equipment needed.


I have seen a handful of people on DIY forums weld what appears to be thin walled aluminum with a spool gun for similar projects. Is it even possible to weld 1/8” aluminum tubing given my experience and equipment? Could the welds be load bearing? What can I do to ensure success with good penetration and welds (besides proper cleaning of aluminum, right voltage, right wire speed, correct filler, push technique, good gas coverage, etc.)


I have done a little research and it seems possible, but I just wanted to get a second opinion before I proceed. Any insight or advice is appreciated. Thanks!

[Oscar]

Assuming you even had perfect technique, no one here knows if you're qualified to design a load-bearing structure. Correct engineering + correct welding = high probability of success. Unfortunately it doesn't sound like you have either of those qualifications (no offense intended). Yes it is possible, but I think most would agree with me....if you have to ask on a project such as this, ya ain't good enough.

But on the plus side, you can practice welding on a few hundred pounds of aluminum scrap and cut-and-etch until you achieve your desired level of success. Something tells me you don't want to throw away that much money though. You're wanting to get it all in one-shot, which frankly is a hail mary play you shouldn't want to be apart of. So yea it's possible. The real question is: do you have that much disposable income and time to learn how to MIG weld aluminum tubing with a spool gun, and then have the time and effort to design a sound structure?

[Broccoli1]

Do you already have the Lincoln machine and Spool Gun?

Buy some Argon and aloominim and try it out.

You'll see for yerself exactly what Oscar is talking about.

[smithdoor]

I would use steel tubing
If you not setup for welding in aluminum it can be costly needing to rent or buy argon and setup your welder for aluminum welding.
$160.00 for spool gun or upgrade mig gun.
$300.00 for argon and tank.
Maybe regular $150.00 you can find for under $30.00
Wire $30.00 apx
More contact tips.


Most small welders can easily weld steel down to 0.063/ 1/16"

Dave

I am wanting to MIG weld a camper frame out of 6063 aluminum tubing (1”x1”, 1.5”x1.5”, 1.5”x2”, and 2”x4.5”). The tubing would be 1/8” wall thickness. I was planning on using a Lincoln 180 Easy MIG with a spool gun and 100% argon gas; I’m still working out what filler wire I need. But after talking to a welder my dad knows, he was very skeptical on whether or not it would work. He was afraid that I would burn through the tubing and not properly seal the tubing with my welds. He said the way to do it was TIG. I have MIG welded a little bit before (only steel though) but have never TIG welded nor do I have access to the equipment needed.


I have seen a handful of people on DIY forums weld what appears to be thin walled aluminum with a spool gun for similar projects. Is it even possible to weld 1/8” aluminum tubing given my experience and equipment? Could the welds be load bearing? What can I do to ensure success with good penetration and welds (besides proper cleaning of aluminum, right voltage, right wire speed, correct filler, push technique, good gas coverage, etc.)


I have done a little research and it seems possible, but I just wanted to get a second opinion before I proceed. Any insight or advice is appreciated. Thanks!

[Yofish]

Go for it! 5356 wire no larger than .035" dia. 4043 is cheap but weak and prone to cracking under stress. It's funny you posted this because I just today finished repairing a door frame for a Piper PA-12 that was not original. It is made of the oddest AL square tube I've ever encountered - 15/16ths square and only .035" wall with cracks in five joints, only the skin was holding it together. After the first weld with TIG my machine just up and quit so I finished with MIG using .030" 5356. Personally, I wouldn't use TIG as it's slowww and you're not to be worried about appearance. Besides, MIG is whatcha got!

What you are doing isn't brain surgery. Were I you, I'd get some of the material and whack it into 3" or so lengths and practise, and then practice some more. I have to assume it's a real camper and not just a shell given the material you're using? What is the 2x4-1/2" stuff for? Also, being a camper, the skin will provide rigidity. Many if not most campers are made with a wood frame.

[G-ManBart]

If you already have the welder and spool gun I'd say buy some stock similar to what you would be using and see what happens. If you haven't dealt with aluminum before, it's very different from steel and takes practice.

If you don't already have the welder and spool gun you're probably better off finding a local welder to fabricate it for you.

[filetobeef]

the hardest part is going to find the right settings for good welds. practice first and once you feel confident ,go for it.
just be aware that it's going to be a fairly quick process and gun will have to move at a fast constant speed for decent penetrating and looking welds.
ready to blow holes?

[Welder Dave]

Aluminum Mig uses a push technique rather than a pull technique for steel. Use a dedicated stainless steel wire brush to clean the aluminum before welding.

[Whillyjo]

Thanks for all the insight, it gives me something to think about.

Assuming you even had perfect technique, no one here knows if you're qualified to design a load-bearing structure. Correct engineering + correct welding = high probability of success. Unfortunately it doesn't sound like you have either of those qualifications (no offense intended). Yes it is possible, but I think most would agree with me....if you have to ask on a project such as this, ya ain't good enough.

But on the plus side, you can practice welding on a few hundred pounds of aluminum scrap and cut-and-etch until you achieve your desired level of success. Something tells me you don't want to throw away that much money though. You're wanting to get it all in one-shot, which frankly is a hail mary play you shouldn't want to be apart of. So yea it's possible. The real question is: do you have that much disposable income and time to learn how to MIG weld aluminum tubing with a spool gun, and then have the time and effort to design a sound structure?

I have ran some calculations on the static loading and deflection. The values have come back in tolerable ranges for the cantilever beams so I'm not too worried about it. Most of loading will be taken by the members and the welds more hold everything together. I agree it doesn't sound like I am qualified for producing good welds. Aluminum seems like a whole other beast compared to steel. Unfortunately, it sounds like it is back to the drawing board.

Yofish

Re: MIG welding aluminum tubing
Go for it! 5356 wire no larger than .035" dia. 4043 is cheap but weak and prone to cracking under stress. It's funny you posted this because I just today finished repairing a door frame for a Piper PA-12 that was not original. It is made of the oddest AL square tube I've ever encountered - 15/16ths square and only .035" wall with cracks in five joints, only the skin was holding it together. After the first weld with TIG my machine just up and quit so I finished with MIG using .030" 5356. Personally, I wouldn't use TIG as it's slowww and you're not to be worried about appearance. Besides, MIG is whatcha got!

What you are doing isn't brain surgery. Were I you, I'd get some of the material and whack it into 3" or so lengths and practise, and then practice some more. I have to assume it's a real camper and not just a shell given the material you're using? What is the 2x4-1/2" stuff for? Also, being a camper, the skin will provide rigidity. Many if not most campers are made with a wood frame.

I appreciate the encouragement but the welding portion of this project seems out of my scope now. I am wanting to build a wedge style truck camper. By using all aluminum (instead of 8020 extrusions and steel space frame) I was hoping to make it more waterproof (i.e. four season) and lighter. The larger tubing will form the wedge portion/cantilever over the truck cab. I was planning on usually aluminum sheet metal riveted to the frame so I think it wouldn't add to the rigidity too much.

https://expeditionportal.com/forum/t...pop-up.137366/

https://www.tacomaworld.com/threads/...-metal.491406/

https://www.tacomaworld.com/threads/...camper.604686/

• G-ManBart
  Re: MIG welding aluminum tubing
  If you already have the welder and spool gun I'd say buy some stock similar to what you would be using and see what happens. If you haven't dealt with aluminum before, it's very different from steel and takes practice.
  
  If you don't already have the welder and spool gun you're probably better off finding a local welder to fabricate it for you.

I have the welder but no spool gun, gas, or filler wire. I was wanting to see if it was possible first before I pull the trigger. I would definitely be practicing with similar stock to get the settings and technique dialed. I have thought about hiring a local welder to fabricate but I think that would blow the budget and plus I enjoy projects.

I would use steel tubing
If you not setup for welding in aluminum it can be costly needing to rent or buy argon and setup your welder for aluminum welding.
$160.00 for spool gun or upgrade mig gun.
$300.00 for argon and tank.
Maybe regular $150.00 you can find for under $30.00
Wire $30.00 apx
More contact tips.


Most small welders can easily weld steel down to 0.063/ 1/16"

Dave

That is fairly costly just to start experimenting.

[smithdoor]

The cost of setup for aluminum welding is why I say use steel tubing.

Some here have everything in shop. In my case I just fill tank.
But I work steel because it lower cost.
I like using just flux core it will weld down to 24 gauge.

Dave

Thanks for all the insight, it gives me something to think about.


I have ran some calculations on the static loading and deflection. The values have come back in tolerable ranges for the cantilever beams so I'm not too worried about it. Most of loading will be taken by the members and the welds more hold everything together. I agree it doesn't sound like I am qualified for producing good welds. Aluminum seems like a whole other beast compared to steel. Unfortunately, it sounds like it is back to the drawing board.


I appreciate the encouragement but the welding portion of this project seems out of my scope now. I am wanting to build a wedge style truck camper. By using all aluminum (instead of 8020 extrusions and steel space frame) I was hoping to make it more waterproof (i.e. four season) and lighter. The larger tubing will form the wedge portion/cantilever over the truck cab. I was planning on usually aluminum sheet metal riveted to the frame so I think it wouldn't add to the rigidity too much.

https://expeditionportal.com/forum/t...pop-up.137366/

https://www.tacomaworld.com/threads/...-metal.491406/

https://www.tacomaworld.com/threads/...camper.604686/


I have the welder but no spool gun, gas, or filler wire. I was wanting to see if it was possible first before I pull the trigger. I would definitely be practicing with similar stock to get the settings and technique dialed. I have thought about hiring a local welder to fabricate but I think that would blow the budget and plus I enjoy projects.


That is fairly costly just to start experimenting.

[Oscar]

Thanks for all the insight, it gives me something to think about.


I have ran some calculations on the static loading and deflection. The values have come back in tolerable ranges for the cantilever beams so I'm not too worried about it. Most of loading will be taken by the members and the welds more hold everything together. I agree it doesn't sound like I am qualified for producing good welds. Aluminum seems like a whole other beast compared to steel. Unfortunately, it sounds like it is back to the drawing board.

I have the welder but no spool gun, gas, or filler wire. I was wanting to see if it was possible first before I pull the trigger. I would definitely be practicing with similar stock to get the settings and technique dialed. I have thought about hiring a local welder to fabricate but I think that would blow the budget and plus I enjoy projects.


That is fairly costly just to start experimenting.

I see you're a fair bit more prepared than I assumed, if you can run those calculations. That's a good thing, for sure. And yes, aluminum welding via practically any process except for DC stick welding, is VERY expensive. A used AC TIG would be your best bet IF you can find a really good teacher and if you can find enough scrap to practice non-stop, every day, for a few weeks. A bandsaw or portaband would be a necessity to cut-and-etch and validate your technique and joint penetration. It can be done, rest assured. It's just: how bad do you want it, can you afford it, and do you have enough free time to truly devote to it. I'd happily rent you one of my pulse MIGs that can weld aluminum from 0.030 up to 5/8" if you were local. I haven't used the big momma MIG in 6 months, lol.

I think this was some 1/8", maybe 0.100" ,can't remember. Eazy peazy with Pulse MIG (don't mind the two short beads, those were testing an air-cooled TIG torch.)

[M J D]

Mig welding smaller size aluminum tubing is a challenge. Heat control is the issue. Starts are often cold, then as the weld heats up, it's often too hot. Think of trying to get all parts of an ice cube partially melted without blowing it away. Larger tubing or welds on sheet or plate are much easier to pull off. It's certainly doable but it's an entirely different deal than working with smallish steel tube. Also aluminum requires a lot more amps so duty cycles also come into play.

[smithdoor]

Good point on a good challenge.

Dave

Mig welding smaller size aluminum tubing is a challenge. Heat control is the issue. Starts are often cold, then as the weld heats up, it's often too hot. Think of trying to get all parts of an ice cube partially melted without blowing it away. Larger tubing or welds on sheet or plate are much easier to pull off. It's certainly doable but it's an entirely different deal than working with smallish steel tube. Also aluminum requires a lot more amps so duty cycles also come into play.

[shovelon]

5356 is your friend on a cyclically loaded alum trailer weldment. Once you consider that then competency with a good welder is in order. Then proper joint preparation will certainly involve deep beveling and tight fitup.

6063 is an architectural alloy. 6061 as a structural alloy would be proper for something like this with a good stress relief after welding to prevent fatigue. Overheating of the base metal during welding is a danger so a maximum interpass temp of 250 degrees F. is to be maintained at all times(see AWS D1.2 for more info on this).

Here is a good guidebook for welding alum. https://pubs.aws.org/p/280/prgwa-the...ons-historical

[Poleframer]

I picked up one of these a few months ago
https://www.ebay.com/itm/Mountain-18...oAAOSwpdJdVWtb
I'm quite impressed with the build quality, and the 20 foot cord is worth the few bucks more than the cheaper ones.
I adapted the plug end to work on a hobart beta mig I use. Once the cover is off, the plug end just screws in with 1/8" npt, I would guess all you would need to do is buy a lincoln plug end, and put screw it on, after plugging off the hole the mig wire feeds through.
If your mig isnt spool gun ready, I doubt diverting the power to the feed motor with a dpdt switch, and figuring out the contactor switch wouldnt be too difficult.
You might even contact the seller and ask if they have lincoln set ones available. They had pretty fast shipping to me.

[Whillyjo]

The cost of setup for aluminum welding is why I say use steel tubing.

Some here have everything in shop. In my case I just fill tank.
But I work steel because it lower cost.
I like using just flux core it will weld down to 24 gauge.

Steel seems like an easier option and more cost effective. I apprehensive about it due to the increase in weight and corrosion resistance.

I see you're a fair bit more prepared than I assumed, if you can run those calculations. That's a good thing, for sure. And yes, aluminum welding via practically any process except for DC stick welding, is VERY expensive. A used AC TIG would be your best bet IF you can find a really good teacher and if you can find enough scrap to practice non-stop, every day, for a few weeks. A bandsaw or portaband would be a necessity to cut-and-etch and validate your technique and joint penetration. It can be done, rest assured. It's just: how bad do you want it, can you afford it, and do you have enough free time to truly devote to it. I'd happily rent you one of my pulse MIGs that can weld aluminum from 0.030 up to 5/8" if you were local. I haven't used the big momma MIG in 6 months, lol.

I think this was some 1/8", maybe 0.100" ,can't remember. Eazy peazy with Pulse MIG (don't mind the two short beads, those were testing an air-cooled TIG torch.)

I have the time to dedicate learning this...just don't know about the patience lol. Something to think about. Thanks for the offer of renting but unfortunately located in CA.

Mig welding smaller size aluminum tubing is a challenge. Heat control is the issue. Starts are often cold, then as the weld heats up, it's often too hot. Think of trying to get all parts of an ice cube partially melted without blowing it away. Larger tubing or welds on sheet or plate are much easier to pull off. It's certainly doable but it's an entirely different deal than working with smallish steel tube. Also aluminum requires a lot more amps so duty cycles also come into play

This is what I was afraid of. Would preheating alleviate the cold start? Any way to control the heat as the weld heats up? Is moving quickly the way to go?

5356 is your friend on a cyclically loaded alum trailer weldment. Once you consider that then competency with a good welder is in order. Then proper joint preparation will certainly involve deep beveling and tight fitup.

6063 is an architectural alloy. 6061 as a structural alloy would be proper for something like this with a good stress relief after welding to prevent fatigue. Overheating of the base metal during welding is a danger so a maximum interpass temp of 250 degrees F. is to be maintained at all times(see AWS D1.2 for more info on this).

For dimension of tubing I'm wanting I believe the local shop only carries 6063. It looks like the tensile and yield strength is 50% larger for 6061 vs 6063...which is more than I realized.

I picked up one of these a few months ago
https://www.ebay.com/itm/Mountain-18...oAAOSwpdJdVWtb
I'm quite impressed with the build quality, and the 20 foot cord is worth the few bucks more than the cheaper ones.
I adapted the plug end to work on a hobart beta mig I use. Once the cover is off, the plug end just screws in with 1/8" npt, I would guess all you would need to do is buy a lincoln plug end, and put screw it on, after plugging off the hole the mig wire feeds through.
If your mig isnt spool gun ready, I doubt diverting the power to the feed motor with a dpdt switch, and figuring out the contactor switch wouldnt be too difficult.
You might even contact the seller and ask if they have lincoln set ones available. They had pretty fast shipping to me.

Thanks, I'll look into it.

[Oscar]

Any and all fixes/corrective actions you are trying to take beforehand can only be verified one way: cut and etch. You can speed up, slow down, preheat, not preheat, this that, push, pull, drag, throw, bounce, whatever. The things that remain to be seen is:

Can you produce a convex weld profile with smooth transition at the toes, of large enough throat diameter, with enough depth of fusion, and without excessive fish-eye crater ends? All of those are only gained from learning how to weld, and only then can you be critical of your own welds once you learn how to weld. See, once you learn how to weld it, then you will know exactly what you're doing wrong AND how to fix it. "Pre-applying" fixes to welds that don't exist get you no where.

Buy/obtain scrap aluminum that is a weldable alloy.
Weld it until the cows come home 4x.
Cut on bandsaw.
Etch with EZ-Off oven cleaner.
Post up pictures with discrete settings for each weld attempt.
Then ask for advice on how to get better.

[smithdoor]

A good coat of epoxy paint for corrosion. As weight goes very little difference as steel is strong after welding

Dave

Steel seems like an easier option and more cost effective. I apprehensive about it due to the increase in weight and corrosion resistance.


I have the time to dedicate learning this...just don't know about the patience lol. Something to think about. Thanks for the offer of renting but unfortunately located in CA.



This is what I was afraid of. Would preheating alleviate the cold start? Any way to control the heat as the weld heats up? Is moving quickly the way to go?




For dimension of tubing I'm wanting I believe the local shop only carries 6063. It looks like the tensile and yield strength is 50% larger for 6061 vs 6063...which is more than I realized.



Thanks, I'll look into it.

[smithdoor]

Back in the 1960's you would see EMT pipe used for light weight projects.
You see both welding and brassing.
But this would great for mig or flux core welding. Your supplier is Home depot or Lowes.
EMT Tub is round but can mix with other shap and square tub steel.

Dave

Steel seems like an easier option and more cost effective. I apprehensive about it due to the increase in weight and corrosion resistance.


I have the time to dedicate learning this...just don't know about the patience lol. Something to think about. Thanks for the offer of renting but unfortunately located in CA.



This is what I was afraid of. Would preheating alleviate the cold start? Any way to control the heat as the weld heats up? Is moving quickly the way to go?




For dimension of tubing I'm wanting I believe the local shop only carries 6063. It looks like the tensile and yield strength is 50% larger for 6061 vs 6063...which is more than I realized.



Thanks, I'll look into it.

[Whillyjo]

Thanks for all the advice and answers to my questions, I appreciate it. I'm just trying to set myself up for success the best I can, for any route I go.

[smithdoor]

We are all glad help
Please keep us update

Dave

Thanks for all the advice and answers to my questions, I appreciate it. I'm just trying to set myself up for success the best I can, for any route I go.

[Whillyjo]

I thought I would be complete and continue on this thread with my progress. I can start a new thread if need be.

I didn’t realize how iterative welding was until speaking with this forum and experiencing it first-hand. I picked up a spool gun, gas, wire, and aluminum to start practicing. After practicing for a couple of days, I don’t think I have the settings dialed correctly and am not as consistent as I would like. This could be more of a technique/form problem and just not getting enough practice too.

I used a Lincoln Easy MIG 180 welder with a Lincoln Magnum 100SG spool gun. The gas was 100% Argon and the wire was 0.035” 4043 super glaze by Lincoln. At least on this welder, Lincoln uses alpha/numeric designations for voltage and wire speed respectively. Unfortunately, there are no values associated with these designations in the manual or online. One person online had luck measuring these values with a voltmeter, stopwatch, and tape measure. I did this as well to get a rough idea (or estimate) of the values I was working with. Voltage was measured at each setting via voltmeter (one lead at the contact tip and another at the ground clamp) and pressing the trigger with wire speed off. I did this twice and averaged the numbers but there was little to no variance. The wire speed was calculated by holding the trigger of the spool gun for 6 seconds and measuring the delivered wire. Multiplying by 10 got me IPM. I realize this method isn’t super accurate and there are a bunch of variables to control, but it is something to work with. Here are my results:

Voltage		Inches Per Minute
Dial Setting	Voltage	Dail Setting	IPM
A	18.73	1	0
B	20.16	2	0
C	22.15	3	105
D	24.59	4	165
E	33.94	5	258
		6	335
		7	410
		8	515
		9	558
		10	680

To get a better idea on how voltage and wire speed affect welding aluminum, I tried every combination on a piece of scrap angle aluminum (series unknown, slightly thicker than 1/8”). It seems like voltages of C-D (22.15 to 24.49) and wire speeds of 6-7 (335-410) were where I had the most success. Some of the beads with these settings looked okay and had decent penetration.

Next, I practiced a variety of joints (lap, T, butt) on 6061 .0125”x 1” bar stock. My gas flow was between 35-40 cfh. Here was where I had problems. 10-20% of the welds would look decent. Some of the fillet welds would come out convex and others concave. I had a hard time getting the weld in the “corner” between the two pieces sometimes. It would mostly bead on the lower piece and It wouldn’t nicely fill/pool into the corner and penetrate both pieces evenly. I even trying welding more on the vertical piece. It felt hard to control the bead: I was either too fast and not welding exactly where I want or too slow and the work piece would heat up too much. I tried to mitigate this by cooling in water in between welds.

(The letter/number refer to the settings and the 1, 2 refer to the order of welds on that joint)



The other side of that joint. It produced a crack and penetration went to the other side.






Here are some other practice pieces that were not so good:





I would post more pictures but its only allowing me to attach 5 images.

I removed all of the aluminum oxide mainly with a circular wire brush attached to a drill. Once I wiped it down with acetone as well and another time, I used a fresh flap wheel on an angle grinder. Neither process made much of a difference.

Some things I learned:
· Too low of wire speed and the wire just balls off the end
· As voltage and wire speed increase, the work piece becomes too hot and the weld just blows through
· Seems like smaller pieces (2.5” to 3”) heat up too quickly and the weld harder to control
· Best luck with setting on C and D with wire speed at 5.5-7
· Have to move quickly

I’m trying to be consistent with the variables (i.e. cleaning aluminum, pushing, gun angle, welding speed) but having a hard time producing similar, consistent looking welds back to back. Any thoughts? Anything to change? Are my settings about what they should be?

I ran out of bar stock, but the plan is to order some more and keep practicing. I have some tubing that I can eventually start practicing on. I want to get more consistent first and am waiting for a dry cut saw blade to come in. Sorry for the long lead up to the questions, just wanted to be thorough and explain my thought process.

[tapwelder]

I had a 180C and 100 spool gun. 1/8 material worked alright. It would spray of near maxed the volts and minimizes the wire speed. I posted results here years ago.

Starting gun angle might eliminate some soot. Also, you can pull the nozzle away from the metal quite far without losing coverage.

Make sure every thing is tight inside the machine. I had an issue of burn back and the one lug inside the machine was loose. Caused arcing.

Practice on those pieces. Run flat. Fill them up with weld . After they cool or measure temp as it cool, then use heat as a preheat... See how it welds at temps.

[Mike_L]

I thought I would be complete and continue on this thread with my progress. I can start a new thread if need be.

I didn’t realize how iterative welding was until speaking with this forum and experiencing it first-hand. I picked up a spool gun, gas, wire, and aluminum to start practicing. After practicing for a couple of days, I don’t think I have the settings dialed correctly and am not as consistent as I would like. This could be more of a technique/form problem and just not getting enough practice too.

I used a Lincoln Easy MIG 180 welder with a Lincoln Magnum 100SG spool gun. The gas was 100% Argon and the wire was 0.035” 4043 super glaze by Lincoln. At least on this welder, Lincoln uses alpha/numeric designations for voltage and wire speed respectively. Unfortunately, there are no values associated with these designations in the manual or online. One person online had luck measuring these values with a voltmeter, stopwatch, and tape measure. I did this as well to get a rough idea (or estimate) of the values I was working with. Voltage was measured at each setting via voltmeter (one lead at the contact tip and another at the ground clamp) and pressing the trigger with wire speed off. I did this twice and averaged the numbers but there was little to no variance. The wire speed was calculated by holding the trigger of the spool gun for 6 seconds and measuring the delivered wire. Multiplying by 10 got me IPM. I realize this method isn’t super accurate and there are a bunch of variables to control, but it is something to work with. Here are my results:

Voltage		Inches Per Minute
Dial Setting	Voltage	Dail Setting	IPM
A	18.73	1	0
B	20.16	2	0
C	22.15	3	105
D	24.59	4	165
E	33.94	5	258
		6	335
		7	410
		8	515
		9	558
		10	680

To get a better idea on how voltage and wire speed affect welding aluminum, I tried every combination on a piece of scrap angle aluminum (series unknown, slightly thicker than 1/8”). It seems like voltages of C-D (22.15 to 24.49) and wire speeds of 6-7 (335-410) were where I had the most success. Some of the beads with these settings looked okay and had decent penetration.

Next, I practiced a variety of joints (lap, T, butt) on 6061 .0125”x 1” bar stock. My gas flow was between 35-40 cfh. Here was where I had problems. 10-20% of the welds would look decent. Some of the fillet welds would come out convex and others concave. I had a hard time getting the weld in the “corner” between the two pieces sometimes. It would mostly bead on the lower piece and It wouldn’t nicely fill/pool into the corner and penetrate both pieces evenly. I even trying welding more on the vertical piece. It felt hard to control the bead: I was either too fast and not welding exactly where I want or too slow and the work piece would heat up too much. I tried to mitigate this by cooling in water in between welds.

(The letter/number refer to the settings and the 1, 2 refer to the order of welds on that joint)



The other side of that joint. It produced a crack and penetration went to the other side.






Here are some other practice pieces that were not so good:





I would post more pictures but its only allowing me to attach 5 images.

I removed all of the aluminum oxide mainly with a circular wire brush attached to a drill. Once I wiped it down with acetone as well and another time, I used a fresh flap wheel on an angle grinder. Neither process made much of a difference.

Some things I learned:
· Too low of wire speed and the wire just balls off the end
· As voltage and wire speed increase, the work piece becomes too hot and the weld just blows through
· Seems like smaller pieces (2.5” to 3”) heat up too quickly and the weld harder to control
· Best luck with setting on C and D with wire speed at 5.5-7
· Have to move quickly

I’m trying to be consistent with the variables (i.e. cleaning aluminum, pushing, gun angle, welding speed) but having a hard time producing similar, consistent looking welds back to back. Any thoughts? Anything to change? Are my settings about what they should be?

I ran out of bar stock, but the plan is to order some more and keep practicing. I have some tubing that I can eventually start practicing on. I want to get more consistent first and am waiting for a dry cut saw blade to come in. Sorry for the long lead up to the questions, just wanted to be thorough and explain my thought process.

I think the problem you’re going to run into is the gap range between tap settings and lack of ability to adjust settings independently. I’m not familiar with that specific machine, but to complicate things the voltage output on some machines changes with the wire speed. Something to check.

On the test piece you said was thicker than 1/8”, how much thicker? On 3/16 material with 4043 the wire speed should be a lot higher than you were using, 585 IPM according to Lincoln, voltage of 23V, a touch over 170 amps.

Adding: Some of those look awfully cold. GMAW on aluminum needs axial spray, get down in the short circuit range and you’re going to have serious issues with fusion and other problems.

GMAW-P would probably work well here.

[Whillyjo]

I had a 180C and 100 spool gun. 1/8 material worked alright. It would spray of near maxed the volts and minimizes the wire speed. I posted results here years ago.

Starting gun angle might eliminate some soot. Also, you can pull the nozzle away from the metal quite far without losing coverage.

Make sure every thing is tight inside the machine. I had an issue of burn back and the one lug inside the machine was loose. Caused arcing.

Practice on those pieces. Run flat. Fill them up with weld . After they cool or measure temp as it cool, then use heat as a preheat... See how it welds at temps.

I'll give that a try.

I think the problem you’re going to run into is the gap range between tap settings and lack of ability to adjust settings independently. I’m not familiar with that specific machine, but to complicate things the voltage output on some machines changes with the wire speed. Something to check.

On the test piece you said was thicker than 1/8”, how much thicker? On 3/16 material with 4043 the wire speed should be a lot higher than you were using, 585 IPM according to Lincoln, voltage of 23V, a touch over 170 amps.

Adding: Some of those look awfully cold. GMAW on aluminum needs axial spray, get down in the short circuit range and you’re going to have serious issues with fusion and other problems.

GMAW-P would probably work well here.

Not much thicker than 1/8"...measured it with calipers and it was about .0135".

Whats the best way to check if the voltage changes with wire speed?