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 Starting the Kid CF bike
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SpiderMonkey
recumbent guru

USA
569 Posts

Posted - 07/09/2019 :  07:09:49  Show Profile  Reply with Quote
I agree indicators are overrated. The nice thing about a 'bent is the real front indicator is right there in your field of view, between your feet. But I did feel like a moron erasing the mark after thinking I was so clever in reindexing the twister.

I did rig up the derailleur and shifter and tested it, and I was able to get perfect indexing with the new middle index notch and the original big ring notch, with no derailleur fouling on the main tube either in the granny, just mounting with a single 2mm spacer on the BB right side. So that'll be good.

For the next few adult bikes (next project is an upright for the wife) we're going with microshift thumbies. Micro-friction on left, so works with any front derailleur. Right side is 9-speed shimano index or friction, so again works with anything, or if the indexing goes wonky in the middle of a ride, you can move it to friction and be happy until there's enough time to adjust properly. They're really pretty shifters, and not too pricey at ~$80 a set. Should last forever.

Kid's hands do better with these twisters for now, however.

I think I'm actually going to stick another index notch into this one. One thing I dislike about front index shifting is that the final drop to the granny is sort of an uncontrolled chain throw. Whereas with friction or micro-steps on that side, you get a slower, more controlled drop, that fast, spring-loaded toss toward the center is in my experience more likely to result in a chain drop. I figure another index notch on the way down will give a small pause in the cage-slap toward center that should mitigate that.

If there are too many chain drops, I'll rig up a DIY jump-stop on the post. I generally have real jump-stops on all our bikes, since to me they're cheap, light insurance against annoyance.

--SpiderMonkey

Edited by - SpiderMonkey on 07/09/2019 07:12:08
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mecheic
Starting Member

United Kingdom
5 Posts

Posted - 08/05/2019 :  01:29:35  Show Profile  Reply with Quote
great effort and looking good...
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SpiderMonkey
recumbent guru

USA
569 Posts

Posted - 09/14/2019 :  17:41:24  Show Profile  Reply with Quote
Haven't done much on this lately. School's started, and the wife wanted an upright for her short commute, so that jumped the line in priority.

Fingers killing me today. Upright dropouts are a lot more fiddly to make. Lots of drill, file, and hacksaw, but these should work out well for that.



I should have this bike wrapped up inside a month, then I can get back to finishing the kid bike. It needs the seat stays finished, then some seat fabric designed and made. After I get her on the bike again and confirm body position, I'll design her steering mast and flipit, and after that it'll just be a matter of cable stops and buildup.



--SpiderMonkey
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SpiderMonkey
recumbent guru

USA
569 Posts

Posted - 10/06/2019 :  20:35:10  Show Profile  Reply with Quote
I've been mostly working on the wife's upright, but this weekend I finally made another test at a finish for the bike(s) I'm working on. I had no luck earlier with Duratec Sunshield, which was a bummer because it's got good built-in UV protection, it's really nice and glossy when cured, and it's nice and tough. I was trying some liquid dyes I was told would work with it, but they didn't. They never fully mixed, and left gooey spots. I decided to try some try powdered pigments. Test looked OK, so the kiddo said she wanted gold, and I ended up with this.



I was going for a transluscent pearlescent finish, so this is actually a little too dense. It looks less dense than it does in real life. The color is wild. The opacity changes depending on the angle of the light/viewer. Spots that show CF weave from this angle will be covered in opaque gold from just a bit to the side.

The kid loves it, and wants to name the bike Gold Fang, so I guess it's a hit.

The finish is pretty good. Can use a little high-grit sanding, and when I see what that does to the opacity, I'll probably just put another layer of this down clear.

It's meant to be sprayed, but brushing works OK. I thin it with 10% MEK, then mix the pigments for 2 minutes. Then, I pour off the batch into 5g servings. I catalyze it with 2% MEKP at that point (about 4 drops) and then I've got about 4-5 minutes to both stir and brush it on before it gets a little gummy. After the point of gumminess, you can actually stipple it on and it will add color density and lay flat and not produce bubbling. The odd bubble is fairly easily removed with a heat gun on low.

I get a few boogers in the mix, probably from the cheap brush, but those should sand out.









--SpiderMonkey
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