Saturday, March 14, 2009

Lazy Saturday

...well, not really lazy so much as influenza-addled stupor Saturday. Sarah went out for a ride with the Avery boys that ended up being 4.5 hours, so I was left to entertain my sick (and hung over a bit) self.

Digging around in the shop, I found a lot of interesting stuff gathering dust. Most notably:
-Some really nice plug-in dropouts from Paragon that didn't fit the fork blades I wanted to use them with.
-A pile (15 or so) of tandem chainstays that I bought on a whim (and because True Temper pretty much gave them to me when I ordered some other stuff) and then have never used. I'm still waiting for a 350 pound guy who wants a road bike to show up...

Long story short, I put the dropouts in the ends of the tandem chainstays. Nice fit. Always kind of wanted to make a fork with "aero" blades (not for any good reason, just for giggles, basically). Since the chainstays are WAY beefy, there's plenty of strength there to use them as fork blades.

It was a bit of a pain (because the blades are oval, and don't match up for mitering with my round holesaws) to miter the crown, but not too bad. I had to do some creative vent hole drilling and plug the ends of the blades with foil, since I don't have any appropriately shaped purge plugs.

And the fork came together pretty nicely. I built it to be 465mm x 45mm rake (ie, a close match to an 80mm travel 29er fork) and I suppose I'll ride it myself a bit to see how it feels. Probably not something I'll really ever sell, since I have a grand total of about 10 more of those chainstays left and True Temper isn't making them anymore, but still a neat experiment. If it rides nice, I'll give it to my old college buddy Hassan, probably. And if it rides *really* nice, I'll go find some appropriate oval fork blades (or tandem chainstays) and start offering it as an option.

6 comments:

Anonymous said...

Are those chainstays what you'll use on a commuter fork for me? Thanks, Derek

Feldy said...

Bet if you use a really large hold saw (like EBB sized), the blades would miter decently.

Also, get back to me on why the Stans rims are such a PITA.

Yo, pass that chronic-What!-cles of Narnia....oh, you said Saturday.

Walt said...

Derek -

Sure, I could. Depends on how big you are, what "commuter" means to you, etc. There are certainly some oval stays that would work, though these ones might or might not be ideal.

-Walt

Walt said...

Feldy -

Yeah, I used a 37mm saw. It was pretty close - I could go a little bigger (38) and that would have been a tiny bit better. I think my 52+mm ones would be much too big - the radius _mostly_ matches about a 37-38mm.

It wasn't really that bad, part of the slowness was just me being unfamiliar with all the parts, so it took a while to make sure I wasn't screwing anything up.

Anonymous said...

Pretty cool. How does the weight compare to your regular tapering blade forks?

Walt said...

Hey Mike -

It's 885g (albeit with no powdercoat) with an 8" steerer. I could probably make it a bit (5-10g) lighter by cutting most of the plugs and the rack mounts off of the dropouts (since they're welded in, the plugs don't really need to be there).

So it's basically a 900g fork, give or take a little bit. Probably only appropriate for people under 170# or so? I'll be curious to see how it rides.

For comparison, the usual tapering blades I use are 25.4mm diameter, with 1.3mm/.94mm butting (the thicker section being at the top) or 1.0mm/.7mm (I only use those blades for 'cross forks, generally). These are 1.2/.9mm, which is a nice compromise between the two - still beefy enough for medium/small people on mountain bikes, right in between the other two options.

I should probably just post this into the blog, since I'm sure someone else will ask.