Erich's method is quite nice. When we discussed this in an earlier thread, I thought his method was the best. Back then, I looked into the Alfin process done in the UK and priced an aluminum brake, but it was in the thousands of Pounds Sterling, as I remember. Not bad if you are a rich vintage racing car owner, but a little salty for cheap Vincent owners.
One of the issues is that Irving said he had made a mistake on the diameter of the stock Vincent brake--7 inches was too small for the large diameter wheels he was mating the brakes to. That has certainly proved to be the case with the racing machinery. The 8 inch brakes improve the braking out of the box. As the rim diameter is lowered the braking improves considerably and the handling also becomes much quicker. Combining the larger brakes with the smaller rims is a double boost.
The old Ford Fiesta rear brake drums are 7 inches. When you make new drums, like Bernd, going to 8 inches gives you the ability to enlarge the shoe and take advantage of the larger surface area as well as the better leverage ration of the brake diameter to tire diameter.
Bernds cast iron rings are mechanically locked into the aluminum drum by pouring the aluminum around the cast iron ring that has cleats on the exterior of the cast iron ring.
This is an excellent way of locking the cast iron ring into the aluminum.
Finally, Bernd has used a rather clever internal linkage to make the action of the shoes twin leading shoes. All that is left is the testing. It might take a while to tune the brake for the correct coefficient of friction. That is always time consuming.
Bernd has done a great job designing in some features to his brake that are very unique.
David
