Re: [CR]Dropout alignment tool....

(Example: Framebuilding:Tubing)

Subject: Re: [CR]Dropout alignment tool....
Date: Mon, 30 Aug 04 20:05:59 +1200
From: "Wayne Davidson" <wayne.collect@xtra.co.nz>
Cc: "CR BIKE LIST" <classicrendezvous@bikelist.org>


Hi all, I checked my dropout as per a similar method as Mark S had replied with. I found that to be all OK, I thought it would be, with the SR RD that I took of gave no faults. So now I am guessing that the SR I have fitted is out of alignment. I had replaced all the pully cages with NOS items, and that had made no improvement. I will now make a alignment checking tool for the SR RD, this will at least tell me for certain that this is the problem, and also how much out it is........regards wayne davidson Invers NZ.......

Mark S wrote:- "Plan A" is to use professional tools such as the Park or Campi. But before I got mine, I got the same result (albeit more slowly) with a simple tool made from an axle.

I tapped a piece of heavy wall tubing to 10mmx 1mm, to accept one end of the axle. I threaded on a track nut, backwards, and put on two large, thick washers and threaded it into the tubing. I'd have just enough axle protruding so that if I placed a washer on either side of one tip, the other end of the axle didn't quite reach the other tip. Slide the axle all the way into the back of the slot, and tighten the nut. See http://bikesmithdesign.com/temp/TipAlign1.jpg (20Kb) If the other end of the axle isn't lined up with the back of the slot on the other tip, as in http://bikesmithdesign.com/temp/TipAlign2.jpg (17Kb) bend the tip you are in, using the tubing, not the axle. Now switch sides and repeat.

You should use an axle, threaded rod, AKA AllThread, isn't usually straight enough.

The same tool can be used to align derailleur hangers. Just install a 2nd axle in the tips. and thread the tool into the hanger threads with the axle protruding to the left and the tubing to the right. See http://bikesmithdesign.com/temp/HangAlign.jpg (18Kb) Now check the axles for being parallel. If not, bend into alignment using the tube, not the axle.

Mark Stonich;
BikeSmith Design & Fabrication LLC
http://bikesmithdesign.com