gbumstead

There are no welds on this type of handle bar. No cross bar which can contribute to the bending factor. I had the shop that is bending the bars, over bend the first set of bars 6 degrees and then bend them back to original geometry. I think this will ellinimate most of the problem. I am not trying to get any major structural change from the final baking process, more of a sealant. I read your article and appreciate the insight Steve. Although the Oil dip sounds more fun I can understand the letting cool at room temp if i want the heat process to even remotely affect the material. I trust the company i purchased the raw materials from originally that it is 4130 chromoly and heat treated. I have worked in the bicycle industry for some time and have seen raw chromoly, although steel is very similar. I plan on baking this weekend ill report back with results.

I started with a piece of 7/8 O.D 4130 chromoly tube. Had them bent to make a pair of bicycle handle bars aprox 30" width and 4" rise. The bars bent the first day about 7 degrees at the first bend. My thoughts are to heat treat again after the bending process. Things Ive read and heard from fellow small time manufacturers, heat up the furnace, home oven in my case, to about 450-500 degrees F. let bake for 20minutes and then dip in motor oil to seal the heat process. This is a final touch to the handlebars before production levels. I need to know if this process can harden the chromoly just enough to hopefully prevent bending again. thanks, G