Aliminium 0.6 to 3.0 mm

[ahsommer]

OK.
Got the Kemppi MiniArcMig 180 arriving in a few days. All the bits and bobs for ali included.
Have the moerse bottle of pure argon gas.
Have done a fair bit of metal stick welding with AC welder (oil filled).

Now, the world of Ali is coming at me.
(Why - building my own canopy for my TLC Pickup.)

Getting some scrap bits and bobs of Ali on Tuesday/Wednesday to practice and learn.

From my reading I get the following pointers

• Clean the metal on all surfaces
• Weld within 8 hours of cleaning
• use a Special SS brush to do the cleaning - keep this dedicated to the ali.
• push, don't pull the weld.
• Angle of 10 to 15 degrees moving forward
• Use a heat sink (how important is this?)

Any other tips? Good tutorials?

Do's? Don'ts? Gotcha's? Should'ves?

Cheers (from a usually Sunny SA - chucking with rain at the moment )

 

[Drains]

Don't let the wire oxidise.

For cleaning, finish with a wipe of acetone. Scotchbrite is a good surface cleaner, but if you're using the green stuff, make sure it's not impregnated with soap (it usually is).

 

[malcolm]

You've found the aluminium tutorials on this site already? I'd have thought 8 hours was a little long. I read half an hour but I'm guessing on that one. Cleaning the edges is just as important as cleaning the sides of the plate.

I tried it with an old Clarke welder, so you are much better prepared with your Kempii. I couldn't manage to weld below 2mm sheet. Even on 2mm sheet a backer helped a lot (this could be a squashed copper pipe). But the Kempii will be a lot better than the Clarke so you might find it easier - just need to experiment with scrap to see what you need to do.

 

[ahsommer]

are you referring to the wire or the ali when you say to wipe down with acetone? (being facetious )

I am assuming that the wire is coated so that it won't oxidize?

I've ordered 1mm ali wire - i think it is 4043? not sure. Will check when it arrives on Wednesday.

 

[ahsommer]

You've found the aluminium tutorials on this site already?

I just did!

Been reading Ed Craig's (http://www.weldreality.com/aluminumalloys.htm) which has so much information my brain is fusing!

I kinda thought 8 hours was a bit long as well, but have not found anything to contradict it either.

Yup - agree on clean all sides, seeing as the point is to get rid of contaminants.

In the interests of other newbies, I will take piccies of my welds and post them for critique, advise and eventually, bragging rights! (Ok, that's a glass of Shiraz talking )

Did a fair bit of looking around, research and talking to various folks, and the Kemppi seems to come out WAY ahead for the small welder - especially as it does the thinking for you and tells you what to do. Perfect for me as welding is *not* my main line of work ( IT is )

Cheers

Eric

 

[runnach]

Just remember to up the tip to 1.2 if you are using 1mm dia wire, liner, drive wheels ect, as explained within tutorials. You will be lucky to weld below 3mm unless to have pulse facility, as Malcolm stated, al/al is a different beast using mig process! Also make sure gas pressure is set to approx 10>15 lpm. Make sure you snip off oxidized wire prior to commencing a new of weld.

You state 3mm to be the max you will weld? If possible try to make your runs on the vertical down position, less requirement for a heat sink, but be prepared to go like Billy Whiz on arcing up!!!

 

[ahsommer]

Just remember to up the tip to 1.2 if you are using 1mm dia wire, liner, drive wheels <snip> be prepared to go like Billy Whiz on arcing up!!!

Not 100% sure, but i think that is what is coming with the unit's Ali kit.

That's one question I have neglected to ask iro speed.

A few of the videos I have found (Miller's website) show an amazingly quick rate of forward movement! Is that really the way it is? Looks like about 20cm per minute!

As to the thickness of the material, Kemppi demostrates guys welding 1mm sheet ali.
Thinnest I will get to use is about 1.8 to 2.0 mm, but the average will be 2.5 and 3.0 and some (not a lot) of 4.0 and 5.0 mm checkerplate.

Keep in mind I have never used a MIG welder before - drooled at them - and taught myself stick welding the hard way. Buy welder - start.
So now to ali - buy welder - start.

I'm kinda handy (did anyone hear that horn ? ) so I don't expect this to be a train smash - but do expect a few challenges.

Love this forum though - tonne of information and obviously a bunch of folks willing to help and share information.

Cheers

Eric

 

[malcolm]

If it's your first time at MIG then might be worth getting some steel wire and practicing that first. Alu is trickier than steel to pick up.

Problem is aluminium conducts heat away quickly so you need to put a lot of heat in to get it melting. But the melting point is quite low so it blows holes easilly. Without any backing plate you do need to weld very fast (or use a pulsed setting which the Kempii may well have).

Hold on - did a little search - that welder is speced for aluminium, and it's an inverter powered thing. Hitch might know how it behaves on aluminium, but it should have tricks to get around the usual basic MIG trouble above.

 

[ahsommer]

If it's your first time at MIG then might be worth getting some steel wire and practicing that first. Alu is trickier than steel to pick up.

That's the plan!

Of course, since my first main project will be ali, I didn't get a Argon/CO2 mix as well, but got gasless flux wire for mild steel.
OK OK, I read all over this site that most folks don't like it.
But I'll give it a crack.
If it don't cut it, then I'll still use my arc welder for the time being for steel and the MIG for ali.
(Can't get gas at this time of year hardly)

Who is it that said "The harder I work, the luckier I get"? I recon that applies to "The more I practice, the luckier I get" as well.

Cheers

 

[runnach]

Speed of travel is of course dependent of material thickness, type of joint ect, but with 3mm or less, you will have very little time to hang about!

Also make sure you have more than inadequate ventilation, all welding fume can make you ill, mig welding al/al produces very nasty fume, flu like symptoms but ten time worse! Try to make your stance with your head well away from main plume of fume.

 

[ahsommer]

Thanks for the info about the fumes!
Will take care about that.

Strange - but this isn't mentioned anywhere else!

hmmmmmm

 

[runnach]

Thanks for the info about the fumes!
Will take care about that.

Strange - but this isn't mentioned anywhere else!

hmmmmmm

Check out "tutorials welding safety" within this site, I just noticed the safety part a fews mins ago, makes for some scary reading! But like many different trades, there are pro's and con's while undertaking whatever activities, heed the advice and keep the ozone well away as possible from you.

 

[Cobs]

link to Miller's website ahsommer mentioned:

http://www.millerwelds.com/resources/improving-your-skills/mig/

 

[peterd51]

Hi,

wow! followed the link, clicked on 'projects' near the bottom and the first one is a folding welding table....

there are times when my welding bench isn't wide enough and an 18" by 3 or 4 feet flap on the front of the bench would be a good idea.

Regards
Peter

 

[ahsommer]

Well well well
After all the scaremongering from a quazillion people, telling me I have wasted my money, am an idiot etc. (not from this forum mind you) i have the living proof that they are full of cr@p!

I got machine, loaded all wire etc., and did my first welds on steel chairs, round tubing, painted (I did file off some paint), and repaired 4 chairs (no practice - straight in )
BTW - this with flux wire - no gas - worked like a charm.

I then removed stee sleeve, put in teflon sleeve, removed steel filler wire, put in ali filler, turned on the gas and went nuts.

I had received (from a mate Paul Oxley) some strips of Ali Treadplate, 1.5mm.
this I proceeded to turn into a welders nightmare!

BUT - my very first MigWeld on Ali (and this after only 30 minutes of very intermittent Mig welding in the first place)
Some Pics of the first weld attached.

Critiques please - what is wrong, what is right, suggestions etc.

It was also done outside, gas flow at 15lph, slight breeze.

Cheers (pics of after 1 hour and 2 beers coming )

 

[ahsommer]

And after 1 hour of phaffing around, trying different things, blowing holes, filling them, cutting up, welding back together, the last weld I did before the wind got too much are attached.
Again, suggestions, critiques etc. welcome.

This one also done outside, breeze a bit more, gusty. I'd mastered the stay put at same height and quick wiggle

Cheers

Eric

 

[ahsommer]

Notice the excessive black at the start of the weld.
Why and how do I get rid of it.
Penetration also not good at the beginning.
Do I need to hang about a bit at the start before travelling?

Cheers

 

[snowcat]

Have a read through this thread http://www.mig-welding.co.uk/forum/showthread.php?t=3477 most of this should help you out....

 

[malcolm]

What grade of wire are you using? I'm guessing a 4000 series wire which is fairly soft. Shenion (anaother forum member) uses 5000 series which has some magnesium in that makaes it go a bit black. I suspect you are using 4000 series.

In which case the blackness at the start is not enough shielding gas. Run some gas through the torch before you start welding (pull the trigger for a few seconds then cut off the excess wire). That should get rid of the air in the gas line.

Working outside if it's windy will reduce the gas coverage, but the later parts of your welds look like they have OK shielding.

 

[ahsommer]

Snowcat - I'll check out the link tomorrow - Thanks
Malcolm - using 4043 wire (no idea what grade the ali is - got it as a 'gift' to test with - horses teeth and all that.
It was a bit windy, and the line had stood idle for about 3 minutes before I attacked this weld.
I need more practice to get it 'pretty', but not a single weld I did today could I break.
I actually kind of chuffed!

Thanks

Eric (and if I don't come online anymore - the best of the holiday season to all those reading this and those who have given advice - thanks.)