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frame building questions...?(2 posts)

frame building questions...?hycobob
Oct 23, 2002 11:51 AM
Have any of you do-it-yourselfers built your own frames? I'm considering a 700cc rear wheel recumbent project and am curious about some things... I've thought about using 1.5"OD muffler pipe for a main beam and using a local muffler shop to bend it. The chain-stays are a bit harder though. I've seen bents with and without seat-stays welded to the dropouts. What wall thickness should I use and how can I make the taper at the dropout? Since the stay's tubing is larger than the dropout's tab that inserts into it, and I don't want to invest in high dollar shaped tubing; this presents a problem. Can I cut notches in the end and heat the tubing so it'll bend easily to the correct size and then fill-weld/braize it. Or will this make a weak spot that'll crack where the bend/cut is? I've thought about using 5/8 or 3/4 inch stainless tubing here as I have plenty on hand. I'm unsure as to the strength of the tubing, though it is rated at 3000psig (inside the tubing) and seems to be stiff will it withstand the force of a 185lb rider? Should I think about using a 1/2 inch stainless tubing seat-stay at about 35 degrees to add strength to the rear? Chain management will be fun in a psychotic sort of way, along with seat construction. The front end, though I'm still unsure as to the size of wheel, seems pretty cut and dry...famous last words.
Lots of bent builders here...Nessism
Oct 23, 2002 6:22 PM