Determining AL filler metal to buy for repair job

[Trip59]

So the repair job on the 53' reefer is coming up, decking and some brackets. I know its aluminum, but that's about it. I don't know if this fits better in the commercial repairs section or TIG section, please move if needed.

How in the heck do I determine what type of aluminum it is or is there just a rod that will work? Or should I pick up a couple and see where each gets me?

I haven't seen the job yet, but I'm told it's 1/8-3/16" thick, welded (so I know it can be welded) and has sustained damage due to fatigue and impact. There are some cracks and I believe a puncture or two (or a dent that cracked, not sure). It will be fix what can be fixed and replace what can't.

Heading to the LWS tomorrow or Sat to pick up a bottle and some other stuff, some 309 for a cooling system piece, some tungsten in a bigger size, maybe a pair of gloves. Got the outlet and plug end today, electrician friend picked them up, should be burning metal by the weekend!

[Rodsmachineshop]

use ER4043 since welds more easy and flex's weld better since has silicon in it . this is were its nice to have a aluminum mig spool gun , noticed you have a Atlas 12" engine lathe I have a 14 atlas lathe made in 1936 lol

[srp]

On the parts I weld, 5356 welds a little better than 4043 on the Syncrowave 250 and 250EX. 5356 welds very shinny and 4043 looks very lightly sandblasted compared to 5356. It would be worth trying both fillers.

[everlastsupport]

Like recommended, I would say get both as well. I normally would start with 4043, but they both have there place and worth having in hand. The 5356 is more rigid, magnesium base, the 4043 is a silicon based.

[fdcmiami]

on a trailer, as a rule your extrusions will be 6000 series al and your sheet stock will be 5000 series al. take it from there.