Patch weld with torch

[kato_pup_dog1977]

I can tell that everyone that has posted about oxy welding has extremely limited experience with it. When it comes to "working" the metal after fusing the panels, oxy is THE method to use. MIG welding leaves a brittelized area on both side of the welded seam. This is known as the heat affected zone and often fails if involved in an accident. People lap the joint to lessen this happening and thusly create a place for rust to begin. I have welded many patch panels into fenders, hoods, roofs and many other sheet metal parts. Don't quench the welds immediately after welding as this hardens the metal leading to stress fractures when working the metal. If you need to cool the metal be careful what you do and quickly brush a wet rag on the panel near the weld. If done properly the welded area is hammer and dollied flat and no filler is needed. The welds should be better than 100% penetration and finished from both sides. As for gas pressures, you should really use dual stage regulators and gas pressures around 3-4 psi acetylene and 5-6 psi oxy. Yes, I have the dual regs and can maintain a flame at 2psi for as long as I want and have done so many times. This takes a lot of time and patience! Practice on whatever you get your hands on. Coat hangers are exceptional filler rod! The copper coating on the "proper" rod needs to be removed for the best welds. Be careful who you gather advice from about welding...there are many who think they know best and few who can actually do it. Look into Ron Covell, the man has a ton of info out there for those who desire to really craft sheet metal.

[Dan]

6delta: I agree that "back in the day" coat hangers and such methods were regularly used, I used them myself MANY times, and I actually grew up way out in the sticks myself, no access to nothin', so I totally know what your saying, and it certainly can still work today.

I guess my point in TODAYs time is that the average guy no matter where he is can get the right materials and advice really easily and for cheap, no need to make the job any harder than you have to, especially if you are inexperienced, this very forum he posted on is a perfect example of good help and advice right at his fingertips!!