Originally Posted by
Peterpan1
Get three wedges, that add up to parallel, and beat the centre wedge in to stretch out the tube. There are also sets for expanding muffler tubes. I played around with them at one point in order to come up with something to hold Eccentric BBs. You would need to put something in to protect the steel. You might also need to put a shim in to draw it oversize in one direction.
Ooh, I like the wedge idea. I may be able to make some at work out of aluminum, to protect the steel - two right angle triangles to sit against the inner BB and an isosceles one to drive between them. I should be able to curve the sides of the right angle ones so that they fit the curvature of the BB. Thanks!