Anyone use Lab-Metal to repair cracked aluminum?

[tmckay]

A friend was helping me reassemble my Magna (finally) and had a mishap.  I am thankful for his help because I never could have gotten the  carburetor throats back into the engine intakes without extra arms, but...

Won't explain details, but a misaligned part caused a crack in the air chamber when he torqued a bolt.  Small crack, but all the way through the chamber wall.   I am worried that it will grow over time (why didn't the Magna have a plastic airbox like the GS )

I found some stuff called Lab-Metal.  Anyone use it or anything else to repair polished aluminum?

Trev

[Blueknyt]

simple trick for magna/sabre/interceptpor carb installation. force in the bottom carbs first, then use a ratcheting strap to work the front carbs in, aim the hooks down below the carbs so it doesnt allow the bottom ones to pullup.

[tmckay]

Blueknyt,

 That is a great idea!  I wish I had thought of it.  Maybe next time...

If I could do two Magna/Sabres a year, I might make $1000 :lol:

I'm thinking my next project bike should be an aircooled twin...

Trev

[rcepluch]

Sorry I can not help you about using "Lab-Metal".

However, there is an old shop trick to help stop cracks from growing.  Use a small drill and drill a hole at each end of the crack. This helps to relieve the stress of the crack so it does not progress.  I would examine the crack with a magnifier to make sure you are drilling at the very end of the crack.

Then you could possibly use an epoxy product to seal out air.

Good luck,


Bob

[The Buddha]

OK I thought lab metal was like a filler... not strength... just cosmetic.
Cool.
Srinath.

[tmckay]

Well,

 the manufacturer page says it can be used to repair cracks in engine blocks.  I saw a post from a machinist that said they only use it where there is not going to be a lot of stress.  Maybe the truth is somewhere in the middle.

 I'm thinking it might be good enough to stop a crack from growing due to vibration or thermal expansion/contraction.  There is no real stress on the box, it just sits there and encases the air filter.  Crack is vertical on the top right outside edge, there is no weight bearing there.

Trev