Before a wheel is stripped a record is made of the current characteristics, rim size, spoke pattern, spoke gauge, offset etc.
Building generally involves using a new set of spokes, the exception may be for example if the wheel has a good set of reasonably new spokes in good condition and it is just the rim that needs replacing. If new spokes are to be used stripping down involves carefully removing a set of four spokes in case they are required as patterns for a new set, then cutting out the remaining spokes with bolt cutters.
If the spokes are to be reused the nipples are first soaked overnight in penetrating fluid. They are then removed. This often involves working them backwards and forwards to loosen them. A common problem at this stage is seized nipples – either through corrosion or because someone has tightened them with pliers in the past and crushed the nipple. Nipples can become so seized that they are impossible to remove without snapping the spoke.
Once all of the spokes have been removed a decision is taken as to whether they can be reused or not. If they are to be reused they are now cleaned so that the threads run free allowing proper spoke tensioning.
Any components that are to be reused, often only the hub, are inspected for any problems before rebuilding.
Cleaning and coating.
Depending upon what the customer requires the wheel components are cleaned, polished, powder coated, anodised, chromed or painted.
Lacing is the stage at which the wheel components are loosely assembled. Depending upon the hub design some wheels are easier to assemble than others. The rim is laid over the hub, ensuring that it is the correct way around so that the rim drill pattern matches the wheel offset (dish). The spokes are threaded through the hub, into the rim and a nipple loosely attached. The correct spoke pattern must be maintained with inner / outer / leading and trailing spokes all in the correct location. Once all of the spokes have been assembled the nipples are gradually tightened to a point where they are holding the rim in approximately the correct position, radially and laterally. The wheel is now ready for truing.
Truing is the process whereby the wheel is corrected for lateral, radial, dishing and spoke tension. This is where the art of the Wheelbuilder comes into play. There is no manual that can tell you how and where to tension a particular spoke to achieve a strong, accurate wheel. The Wheelbuilder gradually tensions the spokes to reduce the largest runout and so brings the wheel into true. There are no shortcuts, it is a patient process of gradual refinement and no two wheels are exactly the same to true.
Truing is carried out in a wheelbuilding jig. There are many different designs but they all essentially hold the wheel firm whilst allowing it to freely rotate and they have a pointer mechanism to allow the Wheelbuilder to measure runout. A dishing gauge can be used to measure the hub / rim offset, known as the wheel dish.
The final result is a strong wheel that has each spoke playing a role in holding the rim and hub together in their correct spatial relationship.