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General Information => General => Topic started by: the caveman on September 17, 2008, 05:25:49 am

Title: Can vw cast intakes be welded ?
Post by: the caveman on September 17, 2008, 05:25:49 am
I want to build up some weld so i can match the intake of a 1.6 na to a 1.9 na head. there isn't a lot missing so it would nice to be able to match the whole circumfrence of the d shape to the manifold. Someone told me they can't weld onto cast aluminum. Or is the only solution to have it TIG'd
Title: Can vw cast intakes be welded ?
Post by: saurkraut on September 17, 2008, 05:40:24 am
I recall 'The Parts Place' in Michigan was selling 1.9 heads a few years ago, and was offering to modify 1.6 manifolds to fit the 1.9 D ports.

Tig is probably the safest bet.
Title: Can vw cast intakes be welded ?
Post by: zukgod1 on September 17, 2008, 06:21:23 am
it can be welded in about any fashion other than stick.

Tig would be the best route for sure though.

I've welded Cast alum with a flame torch and a special rod. Turned out really good.  The entire peice needs to be headed up for best results.
Title: Can vw cast intakes be welded ?
Post by: the caveman on September 17, 2008, 07:32:59 am
you just reminded me that i have some aluminum rod at home. i will try it if i can dig it out.
Title: Can vw cast intakes be welded ?
Post by: jtanguay on September 17, 2008, 08:06:37 am
i know a guy that welded two 1.6 manifolds to work on his 2.0 5 cyl diesel.  still works fine.  i think it was tig welded...
Title: Can vw cast intakes be welded ?
Post by: Mark(The Miser)UK on September 17, 2008, 09:18:28 am
What kind of job does Aluminium MIG welding do:?
Title: Can vw cast intakes be welded ?
Post by: Vincent Waldon on September 17, 2008, 11:21:31 am
In the right hands it can work quite well.

Because the wire is so flexible you can't feed it thru the main cable like normal MIG wire and therefore need a spool-gun attachment.  And of course the shielding gas is different as well.
Title: Can vw cast intakes be welded ?
Post by: burnt_servo on September 17, 2008, 12:55:45 pm
Quote from: "Vincent Waldon"
In the right hands it can work quite well.

Because the wire is so flexible you can't feed it thru the main cable like normal MIG wire and therefore need a spool-gun attachment.  And of course the shielding gas is different as well.


not to say the opposite of what you posted , but with a decent wirefeed , you can just replace the steel wire , and just need to switch the type of gas used .....

BUT you need to do the following .......

if the liner is fairly new , you can remove it and wash it out with laquer thinner .

teflon liners are also available .

if the liner is broken , really dirty or old , just replace it with a teflon one

then you need to set the tension on the feed rollers so it slips on the wire rather than bunching up into the rollers when the wire is held motionless at the tip .

you need a new tip in the correct size for the wire used

the wire feed needs to be a 220volt model ... a 110 isn't heavy enough to do a decent weld .
alumimun requires alot of power to be welded properly .

you need to keep the wirefeed cable from the welder as straight as possible  , and shield the nozzle from and moving air that would blow the gas away from the weld .

while your welding you also need to set up how it welds to what is called a " spray transfer " .
gas presure plays a vital role too ..... too much gas can cool the weld too quickly , not enough gas can cause a porous  weld .

and most of all ....

practice practice practice ..... and cut some welds apart to measure how you are doing .


BUT if you had to weld the stuff everyday ... go buy a spool gun and and avoid the pain in the ass of having to have everything "perfect " .
Title: Can vw cast intakes be welded ?
Post by: zukgod1 on September 17, 2008, 02:55:28 pm
I've welded with a reg mig before, it was messy at first but after a few test patches it was ok. Nothing serious but I could make a nice looking weld..

Spool gun would be best but as mentioned above you can weld with a reg mig it's just not as easy.

Also on the point of adjusting the wheels so they will slip, very good advice. I cant tell ya how many feet of wire I wasted due to the wire sticking in the sheath/tip and causing it to pile up just after the rollers.. What a pain.
Title: Can vw cast intakes be welded ?
Post by: Mark(The Miser)UK on September 18, 2008, 02:59:38 am
Thanks Vincent for your words of caution. I've never tried welding Al before. I only have a cheap gas/gasless MIG. My welding is getting better, helped in part by one of those auto masks. My last weld was along 12" of crack in a now unavailable centre section of Quantum exhaust.  Very pleased with myself 8)

Burnt, and Zuk good advice. Having become sick of those wire pile ups, I already do the preferential slip trick to the standard wire.
Title: Can vw cast intakes be welded ?
Post by: the caveman on September 18, 2008, 07:21:05 am
I just tried to weld it with the torch and some aluminum rod, but i have no way to heat up the whole manifold, and i don't think the rod and the flux was right because it didn't stick at all.  I will send it to be TIG'd.
 I also posted this question on Club 80-90 , a UK transporter site and somebody posted a manifold they made up from 2 and JB welded together !
Title: Can vw cast intakes be welded ?
Post by: burnt_servo on September 18, 2008, 01:12:57 pm
you don't have to heat the whole manifold up with aluminum ..... just weld it " normally " .

are you using a oxyacetalyene torch to weld the aluminum ?

assuming you are ;

you need at least one tip size larger , maybe even try 2 tips sizes larger .

also experiment with either a neutral or very slightly oxidizing flame .

cast aluminum is not the same as cast iron ... you can pretty much treat all aluminum as the same .
Title: Can vw cast intakes be welded ?
Post by: the caveman on September 18, 2008, 05:10:22 pm
Okay i just got it TIG'd. If i would have had more time i would have tried welding again with the torch. I really don't think the rods i was using were right. Maybe just straight aluminum instead of the ones i have with a flux on them. Anyways the welding is not pretty, but it's strong enough to hold up to grinding and after i'll just pretty them up with some epoxy putty or something.