Superlight seat clamp

I had some spare fittings left over from making the supercommuter a while back, and I thought it might be cool to try making a super light seatpost clamp such as the ultralight ones made by the German company BTP. Theirs comes in at 6 grams while mine is double that, though I've got some finsihing touches to do, and I haven't got a titanium bolt yet.

Getting closer

I'm finally getting close with my bike.

TO DO:
--Install all of the little fiddly-bits such as waterbottle bosses, cable stops and the front derailleur hanger
--Smooth out the last remaining divits
--Make fittings and Install headset
--Prime
--Paint
--Build
AND THEN RIDE!!

The end is in sight, but there is still a lot of working and waiting to be done on this one. If I could afford all of the necessaries, I could probably do the work in a week, but I'm going to have to delay a while given the state of the budget and whatnot.

Robotics?

I've decided to diversify a bit into robotics. Well, non-animatronic robotics, aka sculpture. Jennifer's birthday-bot, Sturmley the Snowbot, dubbed such because of his composition as well as the timing of his unveiling during the biggest snowfall on record for Philadelphia.

Kids bikes in action, almost

Jude sent me this picture of Shiloh on her Scooter. It's WAAAY too big for her now, but I have faith that she'll get some use of it some day. Just look at that grin!

Second try

My second shot at the BB joint seems to have gone better. I was up till 2 last night futzing with it and when I pulled off the vacuum bag this morning, it looked pretty good. A quick tug on the dropouts shows that the joint itself flexes not a bit, all of the movement is along the length of the stays. I just have to glue in the seatstay bridge, wrap the seat-stay/dropout junction a bit, and sand sand sand sand sand. Oh yeah, then make the headset fitting and paint. I'm probably only slightly more than halfway done time-wise, but it feels good to see the whole frame.

Last niggling doubt: I am a bit worried about my previously mentioned 3d wiggle in the seat tube. My concern is that it will affect my eventual seat position enough to be noticeable. I imagine that If I were to jack up the seat enough, the distortion would be apparent, but I'm hoping that the seat collar, which is located on the centerline of the jig by the seat-tube cone, is close enough to the eventual position of my saddle, that it will be an inconsequential feature. If not, i guess I'll make myself a self-centering seatpost or something.

Trust the jig

 
One odd thing about working with bamboo is that no matter how straight you think the cane is, it always has some sort of linear distortion. This is especially true in my home-grown culms that come from up the river a piece. There is always a major distortion axis, and then a secondary axis of distortion that leaves me wondering if I've gotten the alignment right at the end. In this case, the seat tube bends mostly in the fore-aft direction, but also has a slight deviation left to right, which makes the seat tube a little off center at its midpoint, even though it is perfectly centered at the seat collar and BB junctions. My bet, I'll never notice it once I am astride the bike.

Natural bends

 
I've decided to try my hand at using the natural bends inherent in bamboo to my advantage. Check out the subtle bend of the seat tube to shield the rear wheel.
Wait till I post the seatstays, they've got hips.

Not straight

 
I'm kinda pissed that the vacuum bag screwed up my alignment. It looked pretty good to me! I'm finally getting the technique down well enough to do single-pass carbon layups. I did learn as I sawed this joint apart that there were some voids in the area below the BB shell, not enough to worry me about strength, but enough to make me think a bit about how much I have to saturate each piece of carbon before applying it.

Drillium Dropouts

 
I did a little bit of carving on the left dropout. I'm ever so slightly apprehensive about strength, but I think that the coolness factor outweighs that by a long shot. Worst case scenario involves a blowtorch and some pliers somewhere down the road.