An admitted shoe geek waxes philosophical about running, triathlon, and life in general.
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Tuesday, September 11, 2018

Something happened on the way to the frame jig

Every once in a while, something happens. A mistake is made. It doesn’t get caught until…

And so it was with a frame that was 90% complete, basically just waiting on one more small braze-on part, when I figured out what was wrong.

The idea behind the build was a bike specific to hilly rides and events, a “climbing” bike that was lighter in weight, utilizing 650c wheels of smaller diameter than the standard 700c, and made for the SRAM eTap component group. eTap is SRAM’s wireless electronic shifting groupset, which is a boon to frame builders in that no extra pieces need be added to the frame for the derailleur cables – lighter, fewer heat affected zones (which increases longevity), and generally just really, really cool.

I’d also planned this build to be a specific project within a limited time span when I would be home alone for an entire weekend. A bit of a challenge to myself to see whether I could get this frame completed, sans some finish work and paint, in that time.

And it worked – I had the design ready and tubes in hand, and set to it when the day arrived. By Sunday evening, I had a completely assembled frame. I could do the hand finishing in the cracks of time over the coming weeks, and it would be ready for the “season” of longer and loftier riders.

And then the discussion happened surrounding the groupset. It’s not cheap, by any means, and even with access to wholesale pricing, it’s a chunk of change. It was deemed a lower priority, a “some day” thing at some undetermined later point.

And then… the house happened. The horizon went from "some day" to "the remotest of possibilities ever".
I set the frame aside, it moved with us into the new house, and sat next to the boiler.

I’d take it out and throw the wheels on it occasionally, just to think and look. At one point I leaned it up against my current road bike. Something didn’t look right. I tried to put the frame pump under the top tube. It didn’t fit. That’s when I realized I’d done something very wrong, and went back to the original design, thinking maybe I’d measured to the wrong side of the T-square, or something.

No, it all matched the dimensions of the computer model. Everything fit up nicely according to the printout. But I’d made one error, assuming one dimension that I’d planned to double check, but forgot. So the frame is almost 4 inches too long.

It’s recoverable, but will take some work. Fortunately, the top tube butted section is long enough and the tube is in position such that it can stay attached to the seat tube and just be trimmed at the head tube end. The down tube, though, will need to be cut out at both ends and re-trimmed. So that means a lot of grinding out and sanding at the bottom bracket to get that ready for the new join.

I’ll get that started shortly. And I’ll get it built without the wireless group. That just means a few more bits added onto the frame after getting the head tube in the right place.

Which makes for three frames in the pipeline at near-complete stages. The first being my daughter’s first pedal bike, the second my replacement gravel bike (with clearance for larger tires). 

It’s just a matter of time…