Help with aluminium

[Seano]

We can all have these moments Sean, switch off machine, go outside and smell the coffee. Beats the frustration.

Out of curiosity, what test are you doing?

Cheers..........

Hi runnach
The course I am on is C+G level 2 Tig ally, I decided to do it properly after being pretty much self taught, and doing bits and bobs offshore, and at times having to weld up quite a lot of ally components as part of my job, trouble is I don't really get enough practice as the majority of my work is mechanical engineering, I get everyone else's bits to weld up being the only person remotely capable of welding ally in the workshop....... I also do all the "Tig" Brazing but have got a couple of the other lads into doing it now too, have tried to bring them on and pass on what I have learned regarding tigging ally.....but invariably all I hear are lots of cursing and ally bits bouncing off the walls......... I have a post on here showing some of my first pieces, wouldn't mind some constructive crits from you if you wouldn't mind.....

Sean.

PS a lot of the material at work is cast or extruded ally...... not the easiest thing to learn on.

 

[runnach]

Hi Sean, I deal with SVQ units, C&G went out the window up here years ago, which was a bad move, I have a C&G unit descriptor book in my office, I'll look up course content, is it C&G 3267?

I haven't done any tig brazing, but welding copper and brass, got the tee and nasty cough from fume, wicked stuff!

I'll do a search of your previous posts for a peek at your 1st pieces, but I'm sure our other resident tig hands have already given constructive information, I will take look though............

 

[runnach]

Found them Sean and, as the post goes back to early October, I'd imagine you have come on leeps and bounds by now!

As my above previous post, positive crits from others. I would like to add:-

80 amps, a tad on the low side, profile fine, but a little on the large side, however, on looking at root side, I noted joint was completely closed, bits of pene here and there.

For 3mm al/al sheet, I would at least have the joint gapped at 2>2.5, thickness of filler rod basically (I would use 2.5 filler wire) At least 10mm tack both ends. Commence root run till complete. If you do this correct, you should have full pene along the length of joint. Forgot to add, make sure you burn away both edges of sheet to create keyhole, deposit filler wire into keyhole as you progress, not just a dip of wire, a slight prod to ensure full pene and decent root profile.

Now you may find face side is either flush or concave from top face of sheet. Turn amps down a tad, then go over root with a fill/reinforcing run to build up face side above the flush. Job done. (you may find you have to weave slighty to catch both edges of root run)

Remember to give a good wire brush to both face & root side of tacked joint prior to commencing weld. And I suggest 2.5 dia filler wire for both runs.

Actually, when you become more proficiant, one run does the job, just push in plenty filler to ensure good root pene and, face side above the flush.

HTH?

Cheers..............

 

[Seano]

Found them Sean and, as the post goes back to early October, I'd imagine you have come on leeps and bounds by now!

As my above previous post, positive crits from others. I would like to add:-

80 amps, a tad on the low side, profile fine, but a little on the large side, however, on looking at root side, I noted joint was completely closed, bits of pene here and there.

For 3mm al/al sheet, I would at least have the joint gapped at 2>2.5, thickness of filler rod basically (I would use 2.5 filler wire) At least 10mm tack both ends. Commence root run till complete. If you do this correct, you should have full pene along the length of joint. Forgot to add, make sure you burn away both edges of sheet to create keyhole, deposit filler wire into keyhole as you progress, not just a dip of wire, a slight prod to ensure full pene and decent root profile.

Now you may find face side is either flush or concave from top face of sheet. Turn amps down a tad, then go over root with a fill/reinforcing run to build up face side above the flush. Job done. (you may find you have to weave slighty to catch both edges of root run)

Remember to give a good wire brush to both face & root side of tacked joint prior to commencing weld. And I suggest 2.5 dia filler wire for both runs.

Actually, when you become more proficiant, one run does the job, just push in plenty filler to ensure good root pene and, face side above the flush.

HTH?

Cheers..............

Cheers for the comments runnach, strangely regarding the gap, I have always been told that NO gap with thinnish ally, not by my tutor I hasten to add, also I think I have had a tendancy to "dip" into the wrong part of the pool ie. the centre of the molten pool, I believe I should be dipping at the leading edge, then move then dip then move, I always wandered why I could never quite get those dime's stacked up, always looked like too much metal deposited to me.

Sean.

 

[runnach]

Cheers for the comments runnach, strangely regarding the gap, I have always been told that NO gap with thinnish ally, not by my tutor I hasten to add, also I think I have had a tendancy to "dip" into the wrong part of the pool ie. the centre of the molten pool, I believe I should be dipping at the leading edge, then move then dip then move, I always wandered why I could never quite get those dime's stacked up, always looked like too much metal deposited to me.

Sean.

Hi Sean, I would not regard 3mm al/al as thinnish matl, evident really when you view rear (root face) gap. As I mentioned, you will find penetration full length on root face, if you have a stop start, say in the middle area, re-arc up about 5mm from stop position, allow pool to develop, then proceed forwrd, this method will allow for continuos penetration, this is important if part of test asks for stop/start around middle area of joint, (as per BS4872)

As keyhole opens up, yes deposit to leading edge of weld pool, actually aim for lead edge and, with keyhole open, add filler to below flush of material, this will ensure good pene. But with al/al, it is a bit more forgiving if you do not get latter points actually 100% spot on.

Give it a bash, and let us know how you get on?

Cheers and have a good one..............

 

[Seano]

Hi Sean, I would not regard 3mm al/al as thinnish matl, evident really when you view rear (root face) gap. As I mentioned, you will find penetration full length on root face, if you have a stop start, say in the middle area, re-arc up about 5mm from stop position, allow pool to develop, then proceed forwrd, this method will allow for continuos penetration, this is important if part of test asks for stop/start around middle area of joint, (as per BS4872)

As keyhole opens up, yes deposit to leading edge of weld pool, actually aim for lead edge and, with keyhole open, add filler to below flush of material, this will ensure good pene. But with al/al, it is a bit more forgiving if you do not get latter points actually 100% spot on.

Give it a bash, and let us know how you get on?

Cheers and have a good one..............

Excellent advice runnach, yes all 5 of my test pieces have stop starts in them, 1 butt, 1 o/s corner vert, 1 lap, 1 T fillet, and one tube on flat, will be at it like a wildman after the hols......

Have a good one also runnach.

 

[runnach]

Excellent advice runnach, yes all 5 of my test pieces have stop starts in them, 1 butt, 1 o/s corner vert, 1 lap, 1 T fillet, and one tube on flat, will be at it like a wildman after the hols......

Have a good one also runnach.

Used same technique for all stop starts, back step prior to completing joint.

I'm assuming test is in accordance to BS4872? If so: Butt joint stop/start 50mm around centre line, go for 25mm past c/l, reason: bit more heat in joint, helps to ensure continuos pene. T-Fillet: 1/3 in from in or, last third of joint, go for stop/start last 1/3 (more heat again) ect ect.

If you were testing out using MMA on carbon, this is the reason stop/starts are ground back, thinning out start area to ensure continuos penetration, also make life easier while capping, less build up at stop/starts, which in turn makes for a better looking finished weld.

Time for a wee dram me thinks