Tuesday, November 23, 2010

Bar Stem Combo in the works

After the Oregon Handmade Bicycle Show in Portland, I decided to make a handlebar stem combo for my Retro 29er. The hard lines of the Thomson stem with the Easton carbon bar were not doing it for me.

I spent some time mocking up a handlebar with curves and desired sweep and then rolled one out on the tubing bender.

I really wanted the handlebar stem combo to be curvy to match the lines on the frame, so after a little time with the tubing bender I came up with a curved and ovalized piece of tubing for the stem extension.

The design requires some custom parts and cutting the stem extension on a milling machine. Fortunately I have friends with the required tools. My friend with the lathe made up the custom binder bolt in no time.  Piercing the extension to allow the steerer tube to pass though the stem was a slightly taller order. The tube that the extension was to be made from was now curved and ovalized - which required a bit of thinking on how to go about cutting the hole in the proper plane and also how to go about clamping such a unusually shaped piece of tubing.

With everything that has been going on lately - it took me weeks to setup a time to use the mill. It took about 30 minutes to get the part properly aligned and fixtured in the milling machine and then about 2 minutes to cut the hole.








It is almost ready to weld / braze up.

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