Aluminum boat welding

[Barry]

Yes definitely you need more details I updated my post as following with some pictures from which you can have amps and speed welding parameters:
test result:
6mm thickness - 300 mm long butt joint:
Radiography test – which passes without porosity., sometimes small porosity shows.
Bending test – no cracks observed – result satisfactory
Tensile test – min required 305 Mpa – Result obtained 280 to 285 Mpa
Failure at welded Area. (at moment failed testing piece not sent back from test lab!)
We use 99,9% Argon gas, 1,2 mm ER5183 filler alloy wire (best suitable imported from USA), we use Aceton cleaner before
60 degree beveling sanding (30 degree on both sides)and within 3 minutes welding from bottom "upwards" (standing pieces) .
Key factors, believe, are suitable heat and speed?!

Can you send the picture of the back side of the weld bead sample?

 

[adriano]

Can you send the picture of the back side of the weld bead sample?

Hi Barry
Happy new year to everybody first of all!
Sorry for delay in coming back but am not physically present at the spot where it is being welded.
it was a good question asking to show the back side indeed I believe this is not correct the weld doesn't come through
causing weackness!

 

[Ad Hoc]

...it was a good question asking to show the back side indeed I believe this is not correct the weld doesn't come through...

That would suggest poor set-up and/or insufficient heat, or simply welding speed too fast that is causing the LOP.

 

[adriano]

Yes Ad Hoc you are correct! I think I was sent a trial piece, not the one sent for testing. It was holiday and the concerned person wasn't available so I made a mistake to sent you that picture. I do not think we sent testing sample like that!
Thank you for your time anyhow