TIG welding aluminum

Jeepasaurusrex · Aug 28, 2010

I was humbled today. I thought I could buzz shut a few holes in the transom of Dad's aluminum jet sled today. Boy was I wrong. I put a piece of aluminum as a backer behind the holes and attempted to TIG them shut. The filler material would bond to the backer, but in no way would bond with the transom material. I am thinking it is some sort of alloy. I was using 5356 filler rod. Any ideas on a different filler rod to use to get it to bond? :corn:

psychodelicdan · Aug 28, 2010

Odds are good that it is thin and has corosion on/in it.5053 is the stuff to be using. You could sand the heck out of it.And if you have any aid based aluminum wheel cleaner, the kind that makes it turn white carefully (its very caustic) scrub it and rince well then try it again.The shouldent be made of anything odd.

psychodelicdan · Aug 28, 2010

4043 would be a bit better if you find it cracking as you weld it.

Jeepasaurusrex · Aug 29, 2010

I sanded both sides and used a file to clean out the sides of the hole. I also cleaned the backing material as well. I did try some 5556 I had laying around and had the same results. It was very weird, almost as if the hull material was repelling the filler material. I will give some of the other rods a try and see what I come up with.

Bunk1 · Aug 29, 2010

Paging MarcW...

Jeepasaurusrex · Aug 29, 2010

Yea, no kidding Bunk. :redneck:

dirtygoat · Aug 29, 2010

Can you post pics???

I have no input, because I don't have that kind of experience...

But, would love to see what's going on...

jeepmauler · Aug 29, 2010

I would use a piece of clean(no mill scale)steel as the backer to start with. There is probably a ton of oxidation in the base material(transom). What gas are you useing?

PHILLBILLY1 · Aug 29, 2010

JB WELD!!!:cheer:
or
Mighty Putty

FTW:awesomework:

MarcW · Aug 29, 2010

Is it possible the hull is anodized? it is a common practice for ocean going boats to reduce salt corrosion. it will change the color and add a hard surface of anywere from 1mil to 5mil. There are several types of clear anodizing that can create both matte and gloss type finish.

That said most common AL boats are 5086 or 5052 series hull plates, so a 5356, or 4043 filler should be the correct alloy to try without some sort of material certs from the original manufacturer. some of the skidplates on jetboats are 6061 or 6063 material. some builders use 5086 bottom's with 6063 extrusions backing them, and 5052 side plates on the hull... so it all depends on manufacturer, type, size, finish, material, etc etc.

Sometimes the stern is made up from whatever is left over :flipoff:

Try some 4043 if it isnt anodized, and isnt accepting the 5356... BUT it Sounds like its complete rejection of the filler could be associated with some sort of surface coating. One way or another, if its 5000 or 6000 series, it should be accepting a 5356 OR a 4043. The welds will just have different coloring comparatively to the base metal.

MarcW · Aug 29, 2010

oh yea, and x2 on maulers question of what gas you are using. and probaby a rediculous thick oxidation layer.

MarcW · Aug 29, 2010

So, Drill the hole out 1 or 2 sizes (depending on your drill index :redneck: ) then Grab an uncontaminated (new) scotchbrite pad and backer for a 4 1/2" grinder, Prep it deeper, and weld away

if this does not work, i would suspect something in your equipment or skills :flipoff:

chainsaw · Aug 29, 2010

Soooo, when I buy a tig your coming over and coaching me right?

Jeepasaurusrex · Aug 29, 2010

The boat is a 1973 Valco jet sled, so obtaining the hull specs is next to impossible. I did clean the area around the holes and used a chainsaw file to file away the insides of the holes. I wiped everything down with acetone. I am using 100% argon gas. I am using pure Tungsten (green band) electrodes. I originally tried the red band (2% Thoriated) and had no luck. I did have a gray band (2% Ceriated) it was better than the red, but the green gave me the best results. I ran some test beads on some new material and it runs great. So, the machine and operator are working fine. :fawkdancesmiley:

I may go down to the weld shop and get some samples to see what sticks. :redneck:

Bunk1 · Aug 30, 2010

Jeepasaurusrex said:
The boat is a 1973 Valco jet sled, so obtaining the hull specs is next to impossible. I did clean the area around the holes and used a chainsaw file to file away the insides of the holes. I wiped everything down with acetone. I am using 100% argon gas. I am using pure Tungsten (green band) electrodes. I originally tried the red band (2% Thoriated) and had no luck. I did have a gray band (2% Ceriated) it was better than the red, but the green gave me the best results. I ran some test beads on some new material and it runs great. So, the machine and operator are working fine. :fawkdancesmiley:

I may go down to the weld shop and get some samples to see what sticks. :redneck:

Marc should be home soon. He just spent 7 hours welding on my rig:awesomework:

AJTowers · Aug 30, 2010

Jeepasaurusrex said:
The boat is a 1973 Valco jet sled, so obtaining the hull specs is next to impossible. I did clean the area around the holes and used a chainsaw file to file away the insides of the holes. I wiped everything down with acetone. I am using 100% argon gas. I am using pure Tungsten (green band) electrodes. I originally tried the red band (2% Thoriated) and had no luck. I did have a gray band (2% Ceriated) it was better than the red, but the green gave me the best results. I ran some test beads on some new material and it runs great. So, the machine and operator are working fine. :fawkdancesmiley:

I may go down to the weld shop and get some samples to see what sticks. :redneck:

Get some pics of the job so we can see how you did .:corn: