Thursday, January 04, 2007

They're here!

Yup, first shipment of the redesigned crowns arrived yesterday. Here's a bunch of pictures:



Overall I'm much happier with these than I was with the previous prototype. The fit of the blades in the socket is much better. It's just about perfect with no sanding at all. The steerer hole has a small burr on the top-side which prevented a steerer from fitting right in, but a couple turns with my reamer in there and it's a perfect fit. I thickened up the walls of the sockets a bit as I felt they were a little on the skimpy side before, and I thickened up the cross section of the horizontal members that connect the steerer to the blades. That was good because they're still under design spec, but I accounted for that in my design, so they still meet the factor of safety.
I guess that's one of the hassles of dealing with outsourced manufacturing, I need to modify my designs to accomodate their looser tolerances (but loose tolerances are what make it affordable).
Even despite beefing up a few areas, the crown is slightly lighter than the protoype designs due to the decreased overall height and width. It weighs in about 190 g which I feel is very appropriate for a mtb crown of this style and width. It's certainly much lighter than the old Long shen mtb crowns I used to use, and about half the weight of my hand made wide fork crowns. They're going to look great on my lugged 29'ers.

Billy, you'll have your fork pretty soon!

bbbb

7 comments:

Baba said...

They do look nice, BBBB. Straight blade?

C Matt said...

For sale to the commonfolk? Puhleeeeease?
-Chauncey Matthews

fasterjim said...

Beautiful. Hey, you may not remember me- but we met at Winter Park a few years ago. You were with 2 woment who were preparing for Leadville on a tandem. i was with my wife who had teh pre-Trek Bontrager. Anyway- beautiful work.

Bob said...

Chauncey, email me for information.

Jim, good to hear from you, thanks for the comments.

Baba, no way, rake'em.

bbbb

John Speare said...

oh man. love them. why ceeway or other manufacture doesn't have this as normal part of their line up is beyond me... same question as c matt: can mere mortals buy the crown only?

Bob said...

There's a very good reason why most suppliers don't have something like this: cost. First off you have to design it to the point where an electronic model can be given right to a machine shop. Secondly, they're expensive. I've considered sellign them, but the price I would have to charge makes them less attractive to most folks. The simple fact is people think $60 is a lot for a set of investment cast lugs, so a $75 fork crown turns them off (which is completely ridiculous if you ask me, I'm building frames that usualyl end up about 2 grand, a few bucks more in raw materials is well worth it to me).

I haven't listed them for sale to the public basically for my own insurance reasons, I don't want the liability of other builders customers (It's expensive enough paying liability insurance for my own customers). So for that reason I'll tell you what I've told others for right now, if you're just building a fork for yourself and want to try one and you're willing to pay my price, I'll probably sell you one. But that's about it for right now unless I find there's a real market for these, then I'll change my insurance plan.

bbbb

bjcv said...

BBBB, I'd give you $75 for one, and I wouldn't even be able to do anything with it! -bjcv