Welding Vw transaxles

AZmiik

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I have a '65 transaxle with a cracked bell housing and was trying to repair it
earlier today to no avail. Does anyone know what kind of alloy the
transaxle is composed of. Or if anyone has welded one what kind of filler rod did
you use. We tried a 4130 and 5356 aluminum filler rods but neither one
really wanted to stick. Thanks in advance.

Mike
 

1992f150

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whoa 4130 and aluminum filler rod??? you might at least narrow it down before you just start welding on it. According to a book i have about baja bugs "the transaxle case is cast magnesium..." You can tig weld magnesium but ive never done it. You should talk to Greg from UPS; I know he told me he welds that stuff at work. An easy way to check if a part is steel is to hit it with a grinder, if it sparks its steel (has iron) no sparks its something else. Keep in mind magnesium is flammable so this test might not be wise unless you got a small separate chip of the bellhousing.

Azusa: shame of the foothills
 

AZmiik

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4130 is a grade of aluminum filler rod as is 5356. I was trying to ti weld it but the filler we had in the shop didn't want to fill. In some places after the heat was taken off the weld it would snap and pop and the intended tack just popped off. All I know is the case is some sort of Al-mag alloy that apparently need a specific welding procedure.

Mike
 

ntsqd

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Wouldn't it be easier to go get a different case ? Keep your existing intermediate housing & guts all together so you don't have to have the shifter forks set up again. Just be sure that you get a similar case, i.e. gland nut or 4 bolt pinion bearing retainer.

Then you'll have camp fire fodder....

TS

I used swerve around my halucinations, now I drive right thru them.
 

vwguy

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welding a vw transmission case and or motor is not the smartest thing in the world IMO
they are both composed of part magnesium and when they are caught on fire your done just watch it go and hope nothing else catches on fire
used to work at a buggy shop and one was caught on fire in a sandrail and we just watched it burn nothing you can really do

how ironic is it that most people slow down for speed bumps yet almost all of us here im sure pin it
 

FABRICATOR

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That case is magnesium. They are not hard to weld, but you must use caution. It helps to preheat the case (this speeds up the welding process and reduces warpage). However, the higher temperature it is preheated to, the closer it is to catching on fire. Use argon or argon/helium mix, 3/32 or 1/8" electrode. Filler rod can be AZ 318, AZ 80 or AZ 92, there may be others. You must use caution for fire. If it does start, don't throw it on your nice concrete floor or bench. (It won't be nice anymore) And don't throw water on it. If you weld it in the open, at least have a metal tub or something with a few inches of sand to set it on. You literally must be prepared to deal with a large item that is burning out of control at thousands of degrees and is almost unstoppable. Also, if it does catch on fire, you will have to deal with it with your welding helmet on because it will be too bright to look at.

<font color=orange>The best ideas are the ones that look obvious to the casual observer.</font color=orange>
 

AZmiik

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Well I am planning on getting a new case sometime but its not in the budget right now. So seen as I am supposed to be the dunes next weekend I figured I could take to school and TIG it up with a little help from the Welding Instructor. We already knew about the fire hazards and had oh Sh*& route planned. Of course it never cam to that as it just didn't want to accecpt the filler. Thanks again. Oh and if anyone has a nice trans for cheap lat me know.

MIke
 

vwguy

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type 1 irs or what

how ironic is it that most people slow down for speed bumps yet almost all of us here im sure pin it
 

AZmiik

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type 1 trs is what I have now. I would like to get a bus box but for now any thing would work.

Mike
 

Greg

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If you come by my shop I will give you some mag wire, as we tig and mig the stuff all day, everyday. You will obviously tig it and you shouldn't need to preheat as you cant get that much heat with a tig torch. If you do want to preheat, 400 degrees is about right, hell, you can stress relieve it by post heating to about 450 and hold it there for an hour, but dont try it without a rotating positioner, you will catch it on fire. We ues 4" rosebeuds to preheat parts, and rearly have fires. Just clean the area really well, it'll be a bitch cause all the oil contamination. Then weld away. If it does catch fire, and i really doubt it will (YOU will most likley catch on fire when grinding down the weld, and a spark catches the mag dust on your shirt on fire, woohoo) Dont put water, sand, or anything that is thought to put the fire out, Do your best to "cool" the part with steel plates or use water on the back side of the burning area to draw heat from the fire, it will go out. If you want im sure i could weld it for you.

Greg
 

AZmiik

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Hey thanks for the offer Greg but I am not sure when I will be on OC next. I went down to West Ait (San Deigo Gas Supply) here in Yuma and they said they could bring in some AZ 61. Does this shound about right I tried for the stuff Fabricator sugested and they didn't have any in thier system and at $60 a pound I think I will try the 61 first.

MIke
 

AZmiik

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Ok one more question. I got the AZ 61 it takes and lays down a nice bead. The only problem is I can't seem to get it clean enough. I have ground out most of the crack and did a through wipe down with acetone but as soon as you strick an arc you can see the crap bubbling out of the surface and the crack. Anyone know of a good chemical cleaner that will draw out of hte pores.

MIke
 

FABRICATOR

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You really should be "V-ing" out the crack or cutting through with a small blade. You might try cleaning it while pre-heating. Spraying a cleaner in or forcing it in with shop air is much more effective than wiping it on. Spray ether works well. (Greg?)

<font color=orange>The best ideas are the ones that look obvious to the casual observer.</font color=orange>
 

AZmiik

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I used a cutoff wheel to Vee out the crack but the surounding metal has asorbed quite abit of oil. I hadn't thought of using shop air to force it into the crack. What would you use to pre heat this thin of a casting. I am not sure about a oxy fuel torch it think that the CO2 produced by that and the heat would cause alot of oxidazation that would have to be removed from a hot part. I am open to any suggustions though.

Mike
 

FABRICATOR

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A oxy/acet torch is OK, but keep it moving! Does your TIG have square wave? It cleans much better. You should be able to final heat the area with the TIG torch slowly going over the area and alternately using a stainless wire brush.

<font color=orange>The best ideas are the ones that look obvious to the casual observer.</font color=orange>
 

AZmiik

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Right now I am using a dialarc 250 no square wave. We have a syncrowave 250 in the shop that has it though. I will try using that tomorrow. We have been set it in the sun to take the chill off and then tack the crack in a few spots to do a localized preheat. I am hoping to have this done tomorrow as it would be nice to install it over the weekend. Thanks for eveyones help. Oh and how do you vapor degrease something.

Mike
 

partybarge_pilot

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You have a vapor degreaser.....

large box, open on top. Inside you have a heating eliment and solvent, MEK or trik111 work well ( I think both are illegal to use now). It also has cooling rings around the top to prevent vapor from escaping. Some have ultrasonic agitation as well. Kinda like an industial dishwasher.

After assymbeling a VW motor with cases that had been vapor degreased it "lost" 1/2 quart of oil on initial start up. Big aluminum sponge..........
 

ntsqd

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WOnder if the pure acetylene soot trick is accurate here too ?
If so you can use it to monitor your temp and make sure you don't overheat an area. That is w/o buying some temp indicating sticks.

FWIW the Sprint Car heads I used to fix welded much better after a thorough hot tanking. They would still bubble junk up out of the metal, but not nearly as badly. If you can get them to let it sit in the tank all day, so much the better.

TS

I used swerve around my halucinations, now I drive right thru them.
 
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