Sunday, January 13, 2008

Some bar/stem lovin...

Hey folks,

Been a few days since I last posted; caught up on some of the "business" end of framebuilding such as paying bills, ordering materials/parts, posting items, etc...

The unfortunate truth is that very little time in building frames is spent building frames :^)

I spent today fabbing up the Bar / Stem combo for Roy's bike. Requested was a combo piece with 135mm reach, 10 degree rise, 60cm width, with a gentle bend.

Although the bar/stem is only made up of four parts, it takes 34 individual processes to fabricate them.

Here's a shot beginning to bore the custom binder bolt...

And a shot of the binder bored, tapped, and relieved for the head of the stainless allen bolt.

The binder is designed to seat against the steerer section through the stem extension, so I relieve the adjacent profile to give a firm, tight fit so it is very strong once brazed.

This piece is reminiscent of the old Grove Hotheads in that I like to use an oval extension as well. The bars, however, are 7/8" .035" 4130 without the compound bend in the palm that made the Grove's famous, instead utilizing a straight grip area to facilitate fitting the Rohloff shifter and it's large surface area.

I pierced the oval extension and placed the steerer tube piece through it and brazed in a custom pinch bolt to the rear, giving it a very clean and effective look.

In this shot you can see how the binder will sit behind the steerer section...the additional material behind the bolt will be filed off to give a smooth profile once completed.

and using an 1/8" end mill to slot the binder and rear of the stem.

And a pic of the basic layout just prior to welding...

I mocked up the bike with the frame, fork, bars, and a post with saddle just to see how it looks...everything came out exactly as I had hoped. She's dead sexy from behind (wink, wink)

All that is left to do is to custom fab the firmtech brake mounts (yes, the final parts arrived!) and braze on the chain stay cable guides I made.

Then a quick blast in the cabinet and it's into the paint booth...I've got some awesome plans for this one.



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