How do you weld bicycle frames?
When considering how to weld bicycle frames , you must first decide whether you want to make a steel or an aluminum frame , because the two metals require different skills in welding .
What do you have to consider when choosing the material for a steel bicycle frame?
First of all, it is important to know that high-quality steel pipes are alloyed and have also undergone heat treatment and work hardening. Unfortunately, these properties are not fully preserved when welding such steel pipes, so that one must expect material weakening at the weld seam. Usually, steels with a chromium-molybdenum alloy are used in bicycle frame construction. Knowledge of the alloy of the steel is essential, because the joining temperature of the steel tubes depends on the alloy and can vary greatly.
What else must be considered when welding steel bicycle frames?
If the welding temperature for steel is set too high for the material, the grid structure and thus the structure of the steel changes. If the material then cools down too quickly, it can become brittle or hardened as a result of the welding process. Only if it cools down slowly does the steel have the opportunity to return to its original state.
What do you have to consider when welding aluminium bicycle frames?
Aluminium has a significantly lower melting point than steel, so that during the welding process it is important not to set the temperature too high, otherwise gaps will quickly appear in the weld seam. In addition, one must make sure that the two workpieces to be joined are thoroughly freed of their oxide layer (like rust, only on aluminium) before welding, as aluminium oxide has a much higher melting point than aluminium itself.
Which welding processes are used in bicycle frame construction?
- MIG/MAG weldingTIG weldingAutogenous weldingElectrodes weldingPlasma weldingSpot weldingSubmerged arc welding etc.
Which welding methods can be used “at home”?
Usually bicycle frames are processed with MIG/MAG welding machines or a TIG welding machine. The other processes mentioned are either purely industrial processes or, as in the case of oxyacetylene welding, are losing importance. Both the MIG, MAG and TIG processes are arc welding processes that work with a so-called shielding gas during the welding process. The MIG (metal inert gas) process and usually works with the inert gas argon. MAG is the abbreviation for metal active gas and uses an argon-oxygen-carbon dioxide gas mixture.
Both processes allow the production of rather bulging welds, which is why this technique is not so much used in the field of high-quality bicycle frames, but mainly in the construction of children’s bicycle frames. Like the MIG process, the TIG process works with an inert gas, but has a non-melting tungsten pin as electrode. With the TIG welding technique, even very fine weld seams can be produced.