welding

NO ,You will warp everything, and a map torch will not get hot enough to weld but will get hot enough to do damage. bad idea, save your $$$ and buy a small mig.
 
yes a 110 volt mig will work great, don't try to run a bead on your sheet metal ,spot weld it letting it cool after a few spots.
 
I use oxygen and acetylene torch. Easy to use just watch the heat. And move around on what you are welding.
 
If you are welding in a long section such as a lower half of a door panel or longer patch panel, It would be best to consider a TIG welder at best, or a gas welder if possible. The rapid heat buildup and rapid cooling with a MIG welder produces a narrow heat affected zone (HAZ) leaving the weld very brittle. A TIG weld is noticeably better, leaving a little bit wider HAZ as the lower gas flow rate allows for a longer cool down time, allowing the metal to cool at a slower rate. Gas welding, while appearing to 'old fashion' is actually faster than either MIG or TIG, once you get the hang of it. The greatest advantage of the gas welding is the fact that the heat build up and dissipation is slow, resulting in a wider HAZ and allowing the weld and adjacent metal to self anneal, making them both a malleable area in which you can form and metal shape easier, without damaging the rolls and dies on the power hammers, English wheels and planishing hammers. MIG welds are so hard that many English wheels and planishing hammer dies have been ruined by 'new' users, unfamiliar with the hardness of a MIG weld. After welding by any process, hammer welding/planishing is only required at the welds, but after gas welding the distortion is much more readily accomplished due the annealed/softer surrounding area.

Gas welding aluminum is much easier to 'work' after welding in this manner, but more difficult to determine how wide the HAZ is because aluminum does not change color at the welding temperatures.

just thoughts!
 
Working with metal is about learning how the heat causes the metal to shrink and how to correct the shrink.

Correcting shrink is easy, you just beat it some. Well some careful hammer on dolly work that you learn through practice. So the idea is to do welds that you can hammer properly. I started out doing this many wrong ways and then I found a book and bought some videos (which you can rent from smartflix).

A MIG welder will do a job, but having switched over to TIG I will never go back. The biggest mistake you can do is buy a cheap MIG welder. It is hard enough getting a good weld with minimal added material and if you buy a cheap welder then all the settings will always be between the settings you can set. See the problem with the MIG weld is you are always adding a lot of material. So before you can try to correct the shrink with hammer on dolly work you have to get he metal level. Even then the MIG weld is a bit hard and never quite levels our right.

A TIG welder is a wonderful change. You get this point of heat the melts the metal together, you just occasionally add a dab of a filler rod, mostly to add the silicon (I believe this is the right science) which helps the 'dirty' metal flow together. Since you add so little metal the area is fairly level and soft. It is a dream to correct the shrinkage with hammer on dolly work. The metal if very responsive and even crappy welders (like me) can get metal to be right and hard to find some of the weld line.

A lower cost option to a TIG welder is a very small oxy/act torch tip with low pressure gas. You will get more heat, but you can lay in a nice weld that hammers great. You must also you the right filler rod, there are rods for TIG and MIG and then there are rods for oxy/act. I know if you try the ER70S6 commonly used for TIG (and MIG) it is difficult to oxy/act weld. I have not taken the opportunity to get some proper rod for gas welding and set up my henrob torch to try.

As with most parts of restoration. Knowledge is key. You have to take the time to understand the metal and the welding process for best results. The right setup makes the welding easy and has a huge payoff in job quality, but it is not usually cheap.

FWIW, my TIG welder is a 60's vintage Miller 330A/BP unit. It is large and heavy. Working units are found on craigslist for around $600. They need 220V single phase (check the label) and normal house breakers will limit you to about half the output power. Even just powered on they will make your electric meter spin pretty fast, so keep that in mind. They still liked by pro welders, but they need computer controlled welders today to work with modern metals. So some of the older TIGs are available at lower prices.

Here are some examples of small torches.

Meco Torch

Henrob

Follow the link at the bottom. I have some metalworking hints as well as video titles on my website.
 
an 80.00 ,wire welder from harbor freight welder will do a fine job, low heat and spot weld every 1/4 in" let cool grind come back between spots repeat until you have a solid weld works great for me
 
If you get a MIG, then be sure to NOT use flux core wire. Set the polarity of the machine for using a gas bottle and then use .025 wire if welding sheet metal. You will have fits using .030 or worse .035 wire
 
If you buy a welder. Buy a good one. Don't buy a junky made in china welder. Miller or Lincoln's are good welders. Or even a Hobart is good. Don't use flux core I think it's to messy for sheet metal.
 
You must log in or register to reply here.
Back
Top