I have an aluminum boat hat needs some leak repair, I have a stick welder and really good with it. I went to Home Depot the other day and asked the guy in the tool section what I need to weld aluminum and if I can do it with a stick welder. He said yes but need aluminum welding rods, they did't sell them and I couldn't find them. Does this sound right and has anyone ever heard of these?

 

Yes, the rods are made, but the weld will be poor and will look bad. Plus really thin metal is hard to do with a stick welder. TIG is the best way to do aluminum. If it's just little leaks, there is probably an epoxy product out there for you application. They have epoxy repair kits for aluminum fuel tanks on semis, so that stuff might work for your boat. Run a google or yahoo search and see what you get.

 

where can you find the rods? I tried the epoxy stuff many times, the saltwater eats it up pretty bad or thed constant temp. change makes it come undone fast.

 

I agree with nastruk95 Al is a special kind of welding.stick welding Al is dicy at best with a master welder in the best conditions.A really good welder will tell you that the corrosion between the pieces will almost make tig impossible.stick has less chance

 

One thing about welding aluminum is you don't know when its going to melt. Since steel turns red as it gots hotter its easy to control your heat. Aluminum doesn't change a color as it gets ready to melt. One second its solid then it turns into a puddle. I've tried to weld aluminum before at school with a TIG and I had a hard time. I saw a tv ad for this product called Alumaloy. Its from one of the as seen on tv things, and I've never used it but it looked promising on tv. Website for it is www.alumaloy.net/ You are supposed to be able to use a propane torch you make the repair. Good luck Fred

 

Aluminum needs to be supported before, during, and after welding. Tig is the only way to go for thin stuff. I have welded .020 without any problem. I use a copper backing bar.

 

try J B weld, it says it works well on aluminum, if not heres aluminum electrodes: http://www.arizonatools.com/catalog/detail/13268/

 

You can mig or tig alum or JB weld it but whichever way you go it needs to clean, clean, clean. You will need a wire brush that's dedicated to aluminium
( a brush that was used on steel will contaminate the aluminium). There is aluminum stick rods but they are for heavy stock and they put up an ugly weld.

Smitty

 

thankyou for all your help, I think I'm gonna go ahead and try to use the aluminum sticks, if it turns out bad I canb just file it down.

 

nastruk, you need these electrodes:
http://www.uniweld.com/catalog/alloy...electrodes.htm

5/32" or 1/8" should work well.
NOTE, you must have a welder that can operate in DC. I made the mistake of buying a bunch of aluminum and realizing I don't have DC capability! DOH!!!
AC WILL NOT WORK!!!!

 

if your boat is riveted , you will ruin it , there is a post in this forum on how to make a tig welder using a car altenator, it was really trick and would work well on alluminum, i welded mine with my mig and it worked but it would have been better with the tig, the suggestion about j.b weld was excellent for small repaires and doesnt come off in salt water , use it all the time,bob

 

For starters, your stick welder needs to do DC. An AC only stick welder WILL NOT WELD ALUMINUM. The keys are (many of these were discussed above):
1. Clean the area of the weld. Buy a new stainless steel wire brush and use it ONLY FOR ALUMINUM.
2. If possible, use a mild acid chemical cleaner on the weld area as well. Your welding shop should either sell it, or offer suggestions on where to get it.
3. As mentioned above, support the weld. It works best to have a big chunk of copper behind the weld area...if you can't do that, and you're stick welding very thin aluminum, consider taking a thin piece of aluminum sheet and putting it behind your weld area...and welding the current boat skin into the aluminum sheet.
4. Pre-heating doesn't work so great because the aluminum just sucks the heat away from the weld area. This same attribute also makes it hard to control your weld heat. The biggest key, then, is selecting the appropriate amperage, and keeping your movement consistent. By the time you're seeing that you've been in one place too long, you've burned a big hole. You should practice on some scrap aluminum of about the same thickness, and just get a feel for amps and speed...and then transfer to the boat.
5. Try to get the hole filled in in one pass. If you have to make a second or third pass, you'll have serious problems with shrinkage affecting the rest of the sheet of aluminum/boat hull.

 

"reiterate"

 

thanks so much, I cant wait to try it out and see the results

 

It's been many years since I've done this, early 70's?, but it was heavy cast aluminum and it was stick rods and it I used an old Lincoln ac buzz box with plugs for heat selection. And it put up some ugly gorilla welds.Now it's possible that they no longer make these rods for ac.