Case repair

[Scooterlam]

I've got a 200 case that suffered when the piston skirt fell off and tried to escape helped by the crank.
Usual damage in front of the bump stop and a hair line crack opposite.
What's the best welding method which wont result in distortion.

[coaster]

I think a 'slug' is inserted to absorb the heat and prevent distortion, CS Engineering in Norwich are good or what about the guy that did the Avanti Crankcase induction mods?

[Scooterlam]

I've limited knowledge of welding,
Would electric welding tig or mig. Not sure of the difference, have less chance of distortion than gas.

[Captain Pugwash]

In my opinion Tig is going to give the best weld result, but it has a higher heat transfer to the work piece than MIG.
MIG could be used and can work very well on aluminium having less heat input, but expect a small amount of distortion which ever method is used because alloy expands when it's hot and contracts as it cools, the more welding that's done the more distortion you usually get.

[bob]

Personally I would favour TIG welding over MIG, the finished weld quality on repairs like this is generally higher with better fusion etc provided it is done correctly

[Ralph95]

Tig is the way
where are you based I could weld it and do any machining I Am in somerset