ben2go
Well-known member
I know a lot of people have posted about aluminum welding and repairing cracks.I prefer having cracks tig welded with a water cooled tig set up.Sometimes the metal is to thin even for this.So some have tried pop rivet patches with 3M 5200 marine sealant,JB Weld(or something like it),while others have taken the plunge and bought and aluminum brazing kit.All of the above work.Some a little better than others.Sometimes holes or cracks are in places where you can't easily use the cheapo way out like patches or JB Weld.The best way is welding or aluminum brazing.I'm not real fond of aluminum brazing,BUTTTT a few on here have used it successfully.I have not tried it,but I have welded(stick and mig) and brazed steel sheet metal.Before trying anything,drill 1/16 inch holes at the ends of the crack(s) or punctures.This will prevent any further cracking.It works.I used it when I was a pilot and aviation line service tech.Also works on fiberglass,plastic,polycarbonate(aircraft glass),acrylic(lexan & plexiglass),and other polymer based products that get cracks.Here is a website for aluminum brazing https://www.easyweld.com/ .Here's what I know about it.The area has to be prep exactly as the instructions say.It works best when the surface to be brazed is facing straight up and level.Another secret to brazing a hole is to use a backing plate.Use a different metal to back it,so the weld doesn't drop through the hole.When I braze sheet steel, I used a brass block, to back the hole, while I filled the hole.Let it cool for a minute or two and remove.When brazing aluminum I would use stainless steel or possibly a block of wood soaked in water.I mean literally soaked in a bucket of water while preping to do the weld.The stuff in the link I posted is a little miss leading.It isn't welding as is suggested.It is in fact brazing.The difference is the temperture and strength welding is hotter and stronger,brazing is cooler and less strong.Brazing isn't weak and should last as long as a weld.I hope someone finds this info useful.
