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Technical & Reference Section => Tech and Restoration => Topic started by: nobby on May 02, 2021, 06:06 PM
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I'm trying to fit a set of twin pinch flights to my Quadangle. Bottom Bracket width is 66mm, the sealed bearing BB has two RS12 bearings which are 11.1mm wide, and a spindle sleeve which is 51mm which makes the total width 72.2mm give or take.
Now I know some people bin the spindle sleeve and use the arm retaining bolts and pinch bolts to adjust bearing load, but I?d rather do the job properly. Obviously it should be a case of using basic maths to determine how much to remove from the spindle sleeve, but is it that simple ? Do you just cut to exactly the right length to match the sleeve and bearing width to BB width ? And how do you cut/grind it perfectly square without specialist tools, as obviously a misaligned sleeve edge to bearing is almost as bad as omitting the sleeve.
Hope I'm making sense ( just got home from my local beer garden ) :D
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You shouldn't have to cut the spindle.
There are different washers that come with bottom bracket to take away any slack.
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Sometimes they are too wide. I usually have a selection that are too small I can use spacers on, but I have had to cut them a couple of times.
I use 1" masking tape to create a perfectly straight line around the sleeve. Then I use a Dremel with a reinforced cutting wheel. Slowly go around marking it, before cutting it. I then file off the end with a file.
There are tools you can buy to cut tubes with a hacksaw, but I don't see the point. Let the power tool do the work. I cut bars using the same method too, never gone wrong there either (Oh and I have cut two forks too).
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All sorted :daumenhoch:
The method i used was simply to turn the frame on its head, put the bearings and sleeve onto the spindle and lay it on top of the upturned bottom bracket for quick reference. I then put the vernier caliper on the frame BB, and then on the inner edge of the bearing cup of the assembled Spindle, Sleeve and bearings.
Only had to take a couple of MM off the sleeve so just put a file face up in the vice then gently rubbed the sleeve edge across it carefully until it was near, then checked it with a square edge when close.
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You shouldn't have to cut the spindle.
There are different washers that come with bottom bracket to take away any slack.
It was the Spindle Sleeve that preloads the inner edge of the bearings that i was interested in rather than the spindle itself.
Thanks anyway :daumenhoch: