Monday, November 20, 2006

Showin' and tellin'

Today's edition will be complete with full color photos, something which is becoming a rare treat around this blog.

As I said earlier, my first prototype crown showed up. Here it is in all it's glory:

As I mentioned in previous posts, this one isn't perfect and I'm going to have to do some work with the supplier. The lower span that connects the steerer to the fork blade is below spec. thickness, and the steerer tube bore is under spec as well. In addition, now that I see it in person I have a few ideas on making it slightly more visually appealing without complicating it. I think I'm going to have the from and back face machined down parallel to each other, and put a radius out to the center section (where the steerer goes).


I heart Richard Sachs Lugs:

Quite literally in this case. The customer wanted Richard's lugs, but with the cut-outs changed to look more like hearts. Richard has a geometric shape cast in that's kind of a stylized heart. The customer wanted a more literal interpretation, so I added some brass to fill in parts of the window and re-filed things to what you see here.
I like how the shape of the cut-out follows the shape of the lug edge so nicely.

Richards lugs are really nicely done, simple and tasteful, but with enough room to be a bit creative. I like 'em. These should make for a nice sport-tourer with a little extra flare.

29'er talk:
Yup, here's the first prototype of these too. Can you tell I've been busy?
This one isn't exactly how the finished product will look as they'll have sliding rear dropouts, but it's a close appoximation. It's not quite done here, I still need to add the brake bosses, bottle bosses and cable stops, but you get the idea.
It's fully lugged, clean and tidy, just how I like my bikes. The sliding dropouts will be about the cleanest you've seen, I've been working hard to make them match the style of the bike.

I'm glad I went through the process of building this one up front, I came across a couple of snafu's that slowed me down and I was able to work on ways to solve them now, rather than on a finished frame. This one will just be for show to give the shop an idea of what to expect. They're double oversize tubes, 31.8 top and seat-tube, 35mm downtube. S-bend seatstays and chainstays for great tire clearance, disc and rim brake compatible, suspension corrected for an 80mm travel fork (they'll probably have the Reba or White Bros fork stock).

These are the dropouts I had originally spec'd as I thought the socket style would go nicely with the lugged frame and they'd save me time by not having to file scallops in the dropouts. Well, I used 'em here since I don't have the sliders in yet and I'm glad I'm not using them for the rest. First off, they have 14mm chainstay ports, which is perfect for the 4 year old Columbus mtb chainstays I have, but Columbus changed their stays to a 12.5mm tip now and my stock of old ones is almost gone. So that would be a big hassle. Secondly these really didn't save me much time over regular flat plate dropouts. By the time I smooth the braze around the seat-stay adjustable socket, I could have finished a set of regular dropouts. But on the plus side, they do look pretty good overall, and I like the cast-in disc tabs.

So I'm one step closer to these things being reality, but there are still a few kinks to work out.

and finally, here's a link to a nice video of the state CX race:

http://www.youtube.com/watch?v=Xaio8y-wU1s

About 3/4 of the way through is a nice pan of me rounding the corner into the creekbed dismount. Look for the gold skinsuit. Lots of good footage out there!

bbbb

3 comments:

Anonymous said...

Hi Bob,
I've really been enjoying your blog- especially the 953 frame stuff. That 29'er frame looks great too. I like it's modern look with classic construction. Are those the slant 6 lugs and BB shell from Kirk?
I'm really looking forward to seeing one of the new crowns built up!
Happy building,
Chauncey Matthews

Anonymous said...

Love the look of that lugged 29er frame, particularly with the standard vertical dropouts. Maybe you could leave that as an option for folks who ride with those new-fangled derailleurs.

Bob said...

I might off them with the option for either style dropout, but for the purposes of bikes actually on display at retail shops, I'll probably build mostly with the sliders so people see them, if there's demand for one or the other, I can do that.

The lugs are not Slant six lugs, they're an older MTB lugset from Long-shen. These lugs allow more slope on the top-tube. Unfortunately there simply isn't a good lugset for 29'ers, they all have some glitch, these seem to have the least and still look good!

Bob