- Thread starter RedOrZed
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the snooper
getting older by the day
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correct you need pure argon and tips to suit and possibly a liner but not definate you would have to check
matt1978
www.lorch.eu
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If you are trying to push 1.0 or even 1.2mm Alu wire over 3 or 4 meter torch then you definately need to change your liner. A combi liner, its part teflon/graphite and the part which stays in the torch swan neck is made from Brass to ensure better current transfer.
If you are planning on doing lots of Alu welding, then you would also need to change your rollers, to a 'U' groove type.
If you are planning on doing lots of Alu welding, then you would also need to change your rollers, to a 'U' groove type.
It doesn't look too hard to make up a roller on the lathe, although you'd have to make up a very small knurling tool to fit into the groove.
What's a U type groove? Is it quite a deep one,as the name suggests? If so, surely it can't be too deep otherwise the pressure roller wouldn't do much.
Might be better off buying one LOL
I wasn't planning on doing much ali welding, depends on how it works out I suppose
What's a U type groove? Is it quite a deep one,as the name suggests? If so, surely it can't be too deep otherwise the pressure roller wouldn't do much.
Might be better off buying one LOL
I wasn't planning on doing much ali welding, depends on how it works out I suppose
matt1978
www.lorch.eu
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Hi Mate,
I didn't mean change as in modify your existing rollers, I ment 'change' as in buy the right rollers and swap them on your wire feeder
There are 3 main types of roller. a U, V and Knurled.
U Shape is for soft wires, Alu, Mig Brazing wires etc
V Is for Steel, CrNi's etc
Knurled is for Flux cored wires etc
The U shape is like a half round and helps to prevent the softer wires from being de-formed as would happen if you used the same rollers you use for steel as for Alu. This can then lead to feed problems and birds nesting.
Also, don't have too much or too little pressure on the rollers, as either is just as bad.
I don't know the pressure scales on the feed system on your machine, but on ours we only need put the pressure arms down to about 2 to 2.5 on the scale. This is plenty.
You can tell you have enough as once you have fed the wire through the torch and contact tip, you should be able to apply some pressure with the flat palm of your hand to the end of the wire and it should begin to push your hand back. If it cant push your hand back then the wire should slip on the rollers, it shouldnt birds nest/snag up.
Good luck and let us know how you get on.
I didn't mean change as in modify your existing rollers, I ment 'change' as in buy the right rollers and swap them on your wire feeder
There are 3 main types of roller. a U, V and Knurled.
U Shape is for soft wires, Alu, Mig Brazing wires etc
V Is for Steel, CrNi's etc
Knurled is for Flux cored wires etc
The U shape is like a half round and helps to prevent the softer wires from being de-formed as would happen if you used the same rollers you use for steel as for Alu. This can then lead to feed problems and birds nesting.
Also, don't have too much or too little pressure on the rollers, as either is just as bad.
I don't know the pressure scales on the feed system on your machine, but on ours we only need put the pressure arms down to about 2 to 2.5 on the scale. This is plenty.
You can tell you have enough as once you have fed the wire through the torch and contact tip, you should be able to apply some pressure with the flat palm of your hand to the end of the wire and it should begin to push your hand back. If it cant push your hand back then the wire should slip on the rollers, it shouldnt birds nest/snag up.
Good luck and let us know how you get on.
It doesn't look too hard to make up a roller on the lathe, although you'd have to make up a very small knurling tool to fit into the groove.
What's a U type groove? Is it quite a deep one,as the name suggests? If so, surely it can't be too deep otherwise the pressure roller wouldn't do much.
Might be better off buying one LOL
I wasn't planning on doing much ali welding, depends on how it works out I suppose
Yes you would be better off buying one. The roller has to suit the wire size.
Buy proper aly tips, ie 1mm aly tip, it will be slightly oversized and is made from a different composition than steel tips, usually. A tip that is too much oversized can cause the wire to arc inside the tip.
The U groove is so that the aly sits nicely in the round part of the groove. V shape groove distorts the aly in the V.
Never use knurled rollers on ANY wire if possible as it distorts the wire and leaves little grooves in the wire which can and does cause the wire to arc in the tip and also over time clogs your liner.
Cheers
welding alloy sump
Hi,
I'm about to weld ali for the first time as the sump on my car has a small crack in it where some gorilla has overtighted the sump nut, I presume.
Have been reading up on this forum, thanks for all the info.
Where do I buy these tips for aluminium are they essential or can I use normal ones. I've ordered some 1.0mm wire and will get some sump alloy to practice on.
Failing that how much do you think a mobile welder would charge to come out and do the job?
Thanks
Anjum mig
Hi,
I'm about to weld ali for the first time as the sump on my car has a small crack in it where some gorilla has overtighted the sump nut, I presume.
Have been reading up on this forum, thanks for all the info.
Where do I buy these tips for aluminium are they essential or can I use normal ones. I've ordered some 1.0mm wire and will get some sump alloy to practice on.
Failing that how much do you think a mobile welder would charge to come out and do the job?
Thanks
Anjum mig
the snooper
getting older by the day
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if you are going to weld it yourself you will have to make sure that it is free from any contamination especially in the crack its self where you cant see and yes the tips are essential as you cant fit 1mm wire into a 0.8 tip
i use 1mm alu wire with 1.4 tips in a V roller, the main problem with the V roller is it oval,s the wire so it snags in the tip. if you can use your vernar to measure the max wire diameter and ajust the rollers so max diameter of wire is about 1.2 or so after it passes the roller. with steel wires you got to have bang on proper size of tip but with alu it can be up to 0.5mm wider than the wire no problem.
pedrobedro
Man at Matalan
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If you've got the sump off use some Petro Patch to seal it on the inside rather than go to the trouble of welding it. Make sure it is clean first then apply it according to the instructions and it will last years. You could do both sides to make double sure.
I think you will find with your sump test pieces that they will not weld well as sumps are made in a cast and will probably have some additives to the aluminium, maybe zinc? Worth a try but definatly test pieces first. I also agree with Pedrobedro or better still obtain another sump.
Is this a Saab 900? (Just a guess...
)Hi,
Thanks for all the responses.
Bill, yes it is a Saab c900 are you on uksaabs?
Hence cant get the sump off without removing the engine, can't replace the sump as it's part of the gearbox housing... difficult/ expensive to find a good gearbox (this has only 63000 miles on it). So nothing to lose by trying and potentally a lot to gain. My view on these sort of things is never say never, weigh up the odds and have a go. I have learnt a lot of skills that way and by asking for information on how to suceed.
I'm trying to get information on various solutions including finding someone with a mobile tig welder.
Can always try pertro patch or chemical metal afterwards or replace the gearbox!.
Thanks
Anjum
Thanks for all the responses.
Bill, yes it is a Saab c900 are you on uksaabs?
Hence cant get the sump off without removing the engine, can't replace the sump as it's part of the gearbox housing... difficult/ expensive to find a good gearbox (this has only 63000 miles on it). So nothing to lose by trying and potentally a lot to gain. My view on these sort of things is never say never, weigh up the odds and have a go. I have learnt a lot of skills that way and by asking for information on how to suceed.
I'm trying to get information on various solutions including finding someone with a mobile tig welder.
Can always try pertro patch or chemical metal afterwards or replace the gearbox!.
Thanks
Anjum
Anjum - yes, I'm on UK Saabs. My user name there is... "BillJ" 
Since you certainly don't want to throw away a working gearbox (hard to find and getting harder every day) and it sounds like you prefer not to remove it from the car, I'd honestly leave welding as a last resort. Positional ally MIG welding is likely to be tricky unless you have a very good professional MIG intended for ally welding (I don't know what you have). With a lower-end MIG, it's difficult enough on the bench with brand new, clean parts.
I've been told that the trouble with welding alloy sumps and gearbox casings is that the cast alloy often seems to be porous enough to absorb oil which needs careful and thorough cleaning to remove. Even though the oil is absorbed from the inside, it can affect a weld penetrating from the outside. It's not impossible - I've had a 9000 gearbox casing repaired by welding (off the car and with the gearbox dismantled) but I would expect it to be difficult in-situ.
TIG is not the best for positional work - it tends to be used mainly on the bench, although it's becoming popular for joining steel pipework. You ight find it hard to get anyone to do it without you removing the gearbox for them.
When I had the gearbox replaced on my 900 T16S, the garage I left to do it (I was 500 miles from home when it failed) found the replacement gearbox I sourced to be cracked around the sump drain plug. They repaired it with some variant of liquid metal (I can find out which one if you like) and it has held now for a good 4 years or so.
Since you certainly don't want to throw away a working gearbox (hard to find and getting harder every day) and it sounds like you prefer not to remove it from the car, I'd honestly leave welding as a last resort. Positional ally MIG welding is likely to be tricky unless you have a very good professional MIG intended for ally welding (I don't know what you have). With a lower-end MIG, it's difficult enough on the bench with brand new, clean parts.
I've been told that the trouble with welding alloy sumps and gearbox casings is that the cast alloy often seems to be porous enough to absorb oil which needs careful and thorough cleaning to remove. Even though the oil is absorbed from the inside, it can affect a weld penetrating from the outside. It's not impossible - I've had a 9000 gearbox casing repaired by welding (off the car and with the gearbox dismantled) but I would expect it to be difficult in-situ.
TIG is not the best for positional work - it tends to be used mainly on the bench, although it's becoming popular for joining steel pipework. You ight find it hard to get anyone to do it without you removing the gearbox for them.
When I had the gearbox replaced on my 900 T16S, the garage I left to do it (I was 500 miles from home when it failed) found the replacement gearbox I sourced to be cracked around the sump drain plug. They repaired it with some variant of liquid metal (I can find out which one if you like) and it has held now for a good 4 years or so.
your setting up a difficult job there alright, if your going to go for it you could do a patch with MiG. or you can also weld Alu up with oxy set. you need a special flux that's yellow in color, cant remember the name of it. you dab it around where you want the alu to be joined, heat with the torch until it turns into clear liquid and then stick your filler wire in and the filler metal fills up the gaps, did this out of position no problems and to cast (an alloy wheel off a 4X4) you should look into it. i don't know how heavy your sump wall would be. when you oxy alu you got to get rid of the oxidized coating which has a higher melting point than the alu itself so if you are not careful the metal will just melt away, same goes for tig as well i think. can you get a photo of the damage up onto this tread.
the snooper
getting older by the day
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i wouldnt even attempt it in situ the oil and deposits in the sump will cause nothing but trouble not to mention the fumes in the engine if there is any petrol vapour lurking in the crank case and you blow through the sump you could have a big bang and more damage
