Help with aluminium

[oceanobsession]

Hi all please can you tell me where im going wrong. i havent got any aluminium
rods so ive cut some lenths of 2mm plate and used these till i can buy some
rods tomorrow. im using 10 lpm argon. tungstone is level with the cup which
gets best results. its the distance from the work piece that im having trouble
with. when you hold it about 5mm away from the work piece you get a smooth
purring sound closer makes this sound intermitant purring and very close stops
the purring. ive got the best results at 5mm from the job it also seems to
have more heat at that distance im keeping the torch vertical because if it is
at an angle it seems to melt the rod before you are ready for it how would i
get on with a fillet weld would i have to bring the tungstone out any help
please cheers ocean

 

[oceanobsession]

Another pic

See second pic

 

[runnach]

Hi oceans, not bad work, considering you were using slithers of parent material. The odd touch down, which is understandable.

Now to your Q's try to keep a 70>80 degree torch lead angle, as for rod melting when you have been using lead angle, just pull it further away from the arc, then back in rapid to deposit more.

Personally I prefer about 10>12mm stick out for bead runs on lap, butt joints. For fillet weld, a tad more stickout is required,to make sure arc is directed straight into throat of weld. 45 degree \ with usual 70>80 degree pointing along length of run.

Gas is ok at 10lpm, rememeber a good wire brush to break up oxide film prior to commencing welding.

HTH n Cheers.....

 

[Archie]

From my limited experience as a learner also I'd say that by having the tungsten level with the ceramic you're making your life harder than it needs to be. Pull it out something like twice or three times the thickness of the tungsten so you can see what you're doing a bit better.

Again, from limited experience, I'd say the reason you get intermittent 'purring' at middle distance is because as you add the filler the pool rises towards the tungsten tip. I'm afraid I don't know enough to say which distance is best but Drains mentioned that 2.5 times the electrode diameter is a good distance.

I've been told to keep to torch vertical and have also noticed the filler melting too soon if I start getting a bit lax at keeping the right angle.

EDIT: Don't listen to a word I said about the distance. Drains said no such thing. I'm thinking of something else and getting confused. Again.

 

[runnach]

Oops, forgot to add, 5mm from work is fine, keeping it tight does not allow for heat to distribute as you would want it to. As for noise of machine when arc length varies, are you using transformer or invertor equipment?

Last point, 2mm thick matl is not the easiest for a novice to begin with. I start my laddies on 3mm, a bit more forgiving!! So all in all, you did really well.

Cheers.........

 

[runnach]

I've been told to keep to torch vertical and have also noticed the filler melting too soon if I start getting a bit lax at keeping the right angle.

Is good advice from a starting point of view, but with using correct tilt angles (approx: torch 70 degree, filler 20 degree) this gives the desired angle of both being equal to 90 degree.

For example, torch 90, if you get hung up for a moment, all the heat is directed straight down = burn through if held there for too long. A good example is a fillet weld, correct tilt angle and, the arc force is in fact slighty pushing deposited filler wire in front of your next deposit. Molten pool will look horse shoe shape. Butt joint correct tilt angle: this will allow more control when keyhole opens up, then deposit when required.

Cheers.....

 

[Archie]

Thanks runnach. I get the point about pushing the pool forward. It makes perfect sense. But from my very much novice point of view the less movement of the filler rod required the better! No doubt with practice the movements will become more like second nature so I can divert my attention to the weld, rather than the welding, if you catch my drift.

 

[runnach]

Archie, have you tried this method, use any material type, as long as each piece are exactly the same dimensions:- Two pieces clamped in vice like this >II< no gap of course. Fuse four corners together (tack) then autogenous fuse along joint, length and width. 3mm matl is better, slight weave as you progress, weave ensures edges are well washed in. Maybe try vert up when fusing width of plate. When complete, you should be viewing a nice looking fused weld, dimes and all. Use both hands if you wish, point is, no filler required, less to think about=progress!

Next, do the same, but this time add filler till complete. This should help you achieve good eye, hand co-ordination. Also helps if you use a good stance, I assume you are right handed? Torch hand at reasonable length from your body, which of course is standing left of torch hand looking in, DO NOT look over torch hand, vision is obscured, thus more problem with eye, hand co-ordination. Looking in from left hand side to torch is much easier to see what is going on with joint/weld pool ect. This stance also reduces fume intake.

Practice practice practice, then it will all come together in no time.

Cheers.........

 

[Archie]

No I've not tried that one but I'll certainly give it a go next time round. Thanks! Oh, just to be sure, it's all done vertically?

 

[Seano]

Hi all please can you tell me where im going wrong. i havent got any aluminium
rods so ive cut some lenths of 2mm plate and used these till i can buy some
rods tomorrow. im using 10 lpm argon. tungstone is level with the cup which
gets best results. its the distance from the work piece that im having trouble
with. when you hold it about 5mm away from the work piece you get a smooth
purring sound closer makes this sound intermitant purring and very close stops
the purring. ive got the best results at 5mm from the job it also seems to
have more heat at that distance im keeping the torch vertical because if it is
at an angle it seems to melt the rod before you are ready for it how would i
get on with a fillet weld would i have to bring the tungstone out any help
please cheers ocean

Great results for first attempt ocean, given what you had to work with....

Archie, have you tried this method, use any material type, as long as each piece are exactly the same dimensions:- Two pieces clamped in vice like this >II< no gap of course. Fuse four corners together (tack) then autogenous fuse along joint, length and width. 3mm matl is better, slight weave as you progress, weave ensures edges are well washed in. Maybe try vert up when fusing width of plate. When complete, you should be viewing a nice looking fused weld, dimes and all. Use both hands if you wish, point is, no filler required, less to think about=progress!

Next, do the same, but this time add filler till complete. This should help you achieve good eye, hand co-ordination. Also helps if you use a good stance, I assume you are right handed? Torch hand at reasonable length from your body, which of course is standing left of torch hand looking in, DO NOT look over torch hand, vision is obscured, thus more problem with eye, hand co-ordination. Looking in from left hand side to torch is much easier to see what is going on with joint/weld pool ect. This stance also reduces fume intake.

Practice practice practice, then it will all come together in no time.Cheers.........

Excellent advice runnach, I seem to get days at work when it all gels nicely, then when at college it all turns to RATSH!T which starts me doubting my ability and thinking **** I only have ten weeks to get to test standard...... some hopes....

Sean.

 

[Country Joe]

Oh, just to be sure, it's all done vertically?

No, I think he means just the sides!

CJ

PS - Runnach - keep it coming! I've already become slightly addicted to "building up the square pad thing" from some arc thread or other on here, now I'll be doing the same thing as Archie later on!

I suspect I'm not the only one though - you probably have a group of secret "distance learning" students, that you never even knew about!

 

[Archie]

Last edited by Country Joe; Today at 2:18 PM.. Reason: Punctuation - Archie would have noticed it!!

 

[runnach]

Oh, just to be sure, it's all done vertically?

Sorry, I should have mentioned, all done down hand, but short sides, have a bash at vert up or down, your just fusing metal together so either will do....

Cheers........

 

[runnach]

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..........

 

[runnach]

I suspect I'm not the only one though - you probably have a group of secret "distance learning" students, that you never even knew about!

Oche no I hope not, would remind me too much of being at work

 

[oceanobsession]

Re Help with aluminium

Cheers everyone for the advice. my machine is a transformer based one with
only post gas.it also has a shunt type adjustment for the amps. i can see why
a foot pedel that can control the amps would be more favorable even more
so with aluminium. ive built a 600x1200 welders bench from 50x50 box with
a 8mm top when welding aluminium on top of it it draws the heat away from
what you are welding if you was to clamp the workpiece to the bench but
what you were welding was of the bench still with the same power it would blow holes through your workpiece this temp draw does not seem so bad with
stainless and mild on dc see pic of my welder

 

[oceanobsession]

See pic

sorry pic here

 

[runnach]

Ah an old Cito, never used the one you own tho. Going back to your original post re; arc smoothness while increasing/decreasing arc length, being old transformer technolgy, arc is not as smooth when compared to invertor technology, that said tho, you will still get a very decent weld with the plant you have. Some better than others depending on manufacturer & spec.

Although heat sinks are very benificial behind a weld, heat build up takes a bit longer, but when up to welding temp, burn through will still occur if you hang around for too long!! Remember, al/al has a melting point of 660c, not as forgiving as lcs, st/st. Pity plant did not have "slope in" "slope out" facility, this helps immensely for heat control / running filler wire through fingers.

All in all tho, I think you are being rather critical of your efforts to date, what you have achieved so far is very good!!

Cheers..........

Oops, forgot to mention, if you have plant manual, check out HF gap, maybe HF requires a wee tweek, proper gap makes for a smoother arc??

PPs, if your dabbling inside plant, isolate power by removing power socket, if hard wired into box, set to OFF and remove fuses......Geeeeeeeez

 

[oceanobsession]

Re Help with aluminium

What type of thing am i looking for see pic

 

[runnach]

Could be the area circled yellow, difficult to tell though from pic?

One way to find HF spark unit is (YIKES) set HF to continous, switch on plant and arc up. What you are looking for is a blue frazzle like electric sparking with buzzing like sound, kinda like carbon brushes when using grinder/power drill. Once sourced, isolate plant, but you really require to know HF gap. Feeler guages are required, I recall from a post from Si asking about HF gap for a BOC ADR 375 beastie, HF gap was around 10 thou.

Remeber and take care when powering with panel off and, wear wellies, purely for H&S purposes

HTH?

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

Ps, HF contactors are similar looking to carbon brushes, except normally long and round in shape, badly pitted contactors may require faces ground with an appropriate machine grinder, some makes of plant will have one single contactor, other two.