January 4, 2010

Tom's Welding Pages

A thought on cheap tools:
How many times have you said: "Dang, I wish I would have bought the cheap tool instead!"

There are lots of ways to weld.
Here are what you might call the "Big Four":

I got introduced to welding by borrowing a friends 110 volt MIG unit. Then I got interested in oxyacetylene welding and am now quite taken with it. It is quiet, you can wear comfortable goggles that let you see what you are doing without striking an arc. You can cut metal with an oxyacetylene rig. You can braze with an oxyacetylene rig. The author of my favorite welding book says that if he could have one welder to take to a desert island it would be an oxyacetylene setup. Also note that many people will recommend starting with an oxyacetylene torch and moving on from there, mostly to get a feel for heat control.

Bottles

If you do true MIG welding (with gas) or oxyacetylene welding, you are going to have to deal with the weird issues involved with owning bottles and getting them filled with gas.

Material

You end up needing steel when you are doing welding. The following link has notes about places I use.

Links:

Brazing

Brazing is amazingly useful and solves many problems better than welding would. The big advantage is that brazing does not involve melting the material being joined. A "filler metal" (often bronze) is used which melts at lower temperatures that the stock being joined together.

There is a great online book about brazing.

MAPP gas

This is available is tanks with the same dimensions as the propane tanks commonly used for household repair. It burns much hotter than propane (though the actual temperature depends on the specific torch being used). Not all torches are certified for use with MAPP, so care is advised. One writer says that MAPP gas should only be used with a swirl combustion torch. With such a torch, propane burns at 1750 degrees F, MAPP gas burns at 2400 degrees F. (Acetylene in such a torch would give you 2700 F). MAPP is a trade name for Methylacetylene Propadiene. When used to sweat solder plumbing, it is easy to apply too much heat using MAPP gas.

TIG welding

TIG welders are capable of amazing things, but are priced far out of reach of most people.

Stick welding

A "buzz-box" stick welding rig could be an inexpensive solution for someone who wanted to weld some heavier material. This might be a place where a cheap Harbor-freight unit could be considered, but I bet that you would ultimately regret it. There are things to buy at Harbor-Freight, but I don't think power tools and welders are among them.

A torch set (oxygen and acetylene bottles) allows many more things to be done. You can cut heavy steel with the torch, and braze delicate materials. Remember that oxyacetylene gave birth to other forms of welding, certified airframes can be built using oxyacetylene gear.


Have any comments? Questions? Drop me a line!

Tom's Welding pages / tom@mmto.org