How to weld Aluminum

[Sandun]

Hi Friends

My thermostat housing has a small hole , it is new but unluckily it has a small hole that happend when it make (production ) , how i weld it , can i use Oxygen lamp ?

[Declan_Burns]

Sandun,
Welding aluminium is not easy and certainly not a DIY job. I wouldn't go at it with an oxy acetylene torch as it could melt. I would be inclined to use something more conservative such as JB Weld which is a two component epoxy based putty. JB Weld is very dark grey and I would only use it on the inside. You might have to enlarge the hole to increase the surface area for gluing.

Regards
Declan

[biomed32uk]

I would second the use of JB Weld, it really is good stuff and very useful.

You won't weld ally with Oxy Acetylene, it will just drop onto the floor as a molten lump. TIG is the usual way so if you know someone with an engineering shop that has the facilites.

[philthehill]

You can weld alloy with oxy-acetylene welding equipment.
You do need to have the right welding rods, the right flux and be careful of the heat.
Been there done that.

As regards the problem with the thermostat housing in question - it is a poor quality alloy as regards welding, therefore I would agree that the use of an alloy repair compound would be best so long as the repair compound is suitable for water submersed applications and can cope with the expansion and contraction of the alloy thermostat housing.
Phil

[paul 300358]

When oxy-fuel gas welding aluminum, the problem is that the alloy oxide melts at a far higher temperature than the aluminum. You are far better off TIG welding it. You do need an a/c TIG set, the alternating HF arc ionizes the oxide and removes it.
Paul

[oliver90owner]

If the leak is straight through, simply drill, tap and fit a loctited screw.

Easily electric stick welded with the right rods, or MIG/TIG welded. Not worth the investment for such a minor (pardon the pun) job, mind.

[GavinL]

I recently repaired a very corroded thermostat housing for a Midget, which had much bigger holes in it, using an Aluminium welding kit similar to https://www.chronos.ltd.uk/acatalog/info-DURA01.html which I've had in my tool kit for about 15 years. i was able to fill substantial holes with this and build up the thickness of the heavily corroded housing, it only needs a propane torch. I originally bought it to weld a broken cooling fin back onto a BSA C15 cylinder head, which it did successfully.

Having said that, in this case i would probably drill, tap and plug

[paul 300358]

You can also silver solder it, I think that we used to use Borax flux?

[SteveClem]

Or just buy a new part?

[Sandun]

No chance to buy new parts , it is Marina housing made 1990 year .

[Sandun]

I did it , i found a place Tig welder as you says . Thank you all.

[philthehill]

Well done Sandun.