how many members know how to weld and have a welder at home that is used for their custom bicycle builds?
Tell us what you've got, and what you've done!
Can you or would you help another member in your area, if they need something welded, if they paid you for your consumables?
Whats a consumable?
Welding consumables are as follows:
1-stick electrode
2-mig wire
3-cored wire (flux-cored wire)
4-stainless steel electrodes
5-oxy-acetylene gas welding & brazing
stick electrode
a short stick of welding filler metal consisting of a core of bare electrode covered by chemical or metallic materials that provide shielding of the welding arc against the surrounding air. It also completes the electrical circuit, thereby creating the arc. (also known as smaw, or stick metal arc welding.)
mig wire
like a stick electrode, mig wire completes the electrical circuit creating the arc, but it is continually fed through a welding gun from a spool or drum. Mig wire is a solid, non-coated wire and receives shielding from a mixture of gases. (process is also known as gmaw, or gas metal arc welding.)
cored wire (flux-cored wire)
cored wire is similar to mig wire in that it is spooled filler metal for continuous welding. However, cored wire is not solid, but contains flux internally (chemical & metallic materials) that provides shielding. Gas is often not required for shielding. (process is also known as fcaw, or flux-cored arc welding.)
submerged arc
a bare metal wire is used in conjunction with a separate flux. Flux is a granular composition of chemical and metallic materials that shields the arc. The actual point of metal fusion, and the arc, is submerged within the flux. (process is also known as saw, or submerged arc welding.)
stainless steel electrodes
stainless steel electrodes and wire are used for welding applications where corrosion resistance is required. Stainless steel consumables are designed to match the composition of stainless steel base metals.
Hardfacing
a stick of electrode or cored wire that is designed not to fuse two pieces of metal together, but to add a layer of surface metal to a work-piece in order to reduce wear. An example of this is the shovel on an excavator.
Oxy-acetylene gas welding & brazing
custom building bicycles and human-powered machines with oxy-acetylene welding/ brazing (also known as "gas welding").
There are two kinds of welding equipment, gas, and electric. Electric welding is faster to set up, happens faster, and warps large metal pieces less. However, gas ("oxy-acetylene") welding or "brazing" is more versatile. Since both kinds of welding equipment are expensive, you might be able to afford only one - so go with gas, and you'll be able to accomplish more. You can weld almost any kind of metal with gas, plus you can braze (stronger than welding steel), and cut metals.
one of the strongest ways to attach steel bicycle frame tubing is gas brazing. this is a process similar to soldering, or using hot glue, but with a golden colored metal called brass. Brass is not as strong as steel, and so is not used for knives, or bicycle frame tubing, but is a metal that's very much strong enough to attach steel tubes together. Brass melts at a much lower temperature (1600 fahrenheit - 870 celsius) than steel (2300 fahrenheit - 1260 celsius). As you approach a metal's melting point, the metal crystallizes, and it's alloys can separate. So, if you can stay well below the metal's melting point, you'll end up with a stronger attachment.
Two types of gas brazing
'slip,' 'flow' or lugged' brazing is the most common style. in this technique, frame tubes are joined with sockets called lugs. a large area, encompassing the lug and tubes are heated until brass will melt. Brass rod is placed against the edge of the lug, and melts. Capillary action causes the brass to flow into the lug, filling the gaps between the frame tubes and the inner walls of the lug. Slip brazing is very much like soldering copper plumbing pipes. This is a very strong method of attachment. the drawbacks are:
* lugs are required. Ie lugs are: Lugged headtube, lugged bottom bracket, or even lugged triangle / lugged chainstay dropouts. If you search for vintage bicycle frames or vintage motorcycle frames, you'll find that most of the vintage frame components were cast steel lugged components with sockets, which accepted steel tubing into the lugs to be brazed (gas welded).
* precise fitting is required in order to create gaps of the proper width for the brass to flow.
* cleanliness is very important, because dirt or residuals of oil of any type can cause places where the brass will not flow.
* it is difficult to see the difference between a well executed slip braze, and one that is not strong.
* practice and experience are required for reliable slip brazing.
* if too much brass is added, it pools at the edges of the lugs, requiring reheating or careful grinding to clean up.
To be continued...
C.h.
