John Rumm wrote:

My other "secret weapon" for brazing ferrous or cuprous bits is a
selection of vermiculite "fire bricks" as sold for solid fuel stoves,
with these you can build some containment and reflection for many shapes
(although a transaxle is probably quite difficult).

I do have the cheap Lidl inverter welder, if I had your problem I might
be tempted to get a TIG torch for it.

IIUC you need an inverter than can do AC output to be able to
successfully TIG ali.

(although you could use ali wire in MIG machine with pure argon -
although you either need a good wire feed and a PTFE liner for the torch
lead, or a add on spool gun)

Yes, as I said I do have a little inverter welder *and* a MIG welder
but looking at the extras needed (and skills probably) to use them on
aluminium I decided that brazing was the way to go.

Also, as it's a repair of a crack, *not* having to melt the aluminium
itself is a big plus for brazing. I don't even need it to be
particularly strong, just oil proof.

--
Chris Green
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