Originally Posted by urge2kill
Actually, it is a uni-crown. The blades curve 90 degrees and weld to the steerer. There is no crown intermediary.
Not to worry ...
While I think that the steerer on MOST uni-crown forks extends all way through the shoulders & thereby bolsters the shoulder/etc, even if it doesn't on your fork, if you look at it, the amount of steel that you see should be fairly substantial.
- If in doubt, partially flatten a tin can & drill through it ...
with one of the two holes large enough to accept the recessed nut ...
- mount your brake caliper onto the tin can ...
- you should see that even a comparatively flimsy tin can will present a formidable platform onto which you can mount your brake caliper.
FWIW. Here is a fork whose brake hole I moved UP
after removing the what 'I' deemed to be excess material on the underside of the shoulder ...
The "normal" 39-49 calipers are too short, but the fork will accommodate a 700x32 tire, now ...
Here is a long reach (49-59) caliper mounted to the rear after enlarging forward hole normally used to mount a fender or other accessory on a MTB frame (
!?!) whose cantilever brake mounting bosses were removed from the seat stays ...
Quote:
I got a titanium 5/16" drill bit, but no drill or drill extension will ever get between the seat tube and stays with that bulky 5/16" bit on it. There is 3 inches or less of room.
What are my options regarding non-power tools?
You can fabricate the necessary "tool" by taking a FLAT BLADE, "stubby" screwdriver whose blade you will modify by grinding its taper down to a suitable width which varies between 1/4" (
or, slightly under) to 5/16" (
or, just over AS LONG AS YOU KNOW TO STOP & CHECK the hole BEFORE reaching the wide end of the taper!!!) ...
The
crisper the edges on the taper, the better it will "cut"/(
ream) the hole as you slowly turn the DIY tool in the hole ...
- MOST "flat" files are often fairly brittle, but if you have a set of CHEAPER files, then it may be soft enough to bend the TANG (the end which goes into the handle) 90º and thereby create a tool with more leverage ...
Obviously, the wide end of the tang will need to be 5/16" of an inch, or more, to make this a viable option.
An aluminum brake bridge will be COMPARATIVELY QUICK & EASY to enlarge ...
A steel brake bridge will take more time & patience ... the quality of the edge on your DIY tool will dictate how quickly you can complete the task.
Quote:
I don't know what you just said, but I think I could drill from the other side of the seat stays, expanding both holes, then correct the near hole with that procedure!
I have NOT tried this (
however, I probably will the next time I want to enlarge the forward facing hole on a rear brake bridge to accept a recessed nut), yet ...
BUT, if you want to enlarge the front facing hole on the rear brake bridge from the rear with the aid of a power drill, then you may want to
use a smaller diameter bit (
< 1/4"), wrap the shaft some tape where it would otherwise contact the hole, and then wallow out the forward facing hole ...
Steel is actually incredibly soft, so
CHECK OFTEN (
!!!) so that you don't over enlarge the forward facing hole AND to ensure it is as close to ROUND as possible!
If you STOP wallowing out the hole with the drill bit
before you achieve the necessary 5/16" hole, then you can square & "clean up" the forward facing hole with the fore mentioned, modified stubby screwdriver.