I'm not sure that I understand your question. Doesn't your Schwinn have a seatpost clamp built into the frame?I am using a 74 Schwinn Continential to build a single. Is there a source for a seatpost that will allow a modern seat clamp ? The tube is about 20.8 mm ID
I think I know what you are trying to do. The seatpost you have is like the one on the right and you want to switch to the kind on the left?In the frame yes. I am trying to use a modern seat, must have a "seatpost" that will fit in the frame and clamp to a modern seat.
20.8 is definitely an odd ball size. I have an old Schwinn singlespeed conversion myself. Good luck!Correct, but can not find a post with the small diameter needed to fit my frame. I will probably have to have an adapter turned at a machine shop. Fit it inside the new post, not in a hurry, still looking.
Modern seatposts are aluminum and the OP's is probably steel, so welding is not possible.Just an idea and its really a fairly high risk one if what you have already is working. IF you have access to someone that is a really good welder, why not remove or just cut the top off the seat post you have that will work, and then cut the mount off the type you want and then have the welder put them together?
You can weld aluminum and you can weld steel, but you can't weld aluminum to steel.There is no welding equivalent for aluminum?