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• #118552
I had one milled out (actually he used a clock drill) by a frame builder. Took him 5 minutes.
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• #118553
The frame isn't worth it to be honest, I should just give up but don't like accepting defeat against inanimate objects. Might see if i can get a similar bit for cheap, cheers
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• #118554
The bit isn't the most important part. You need the proper machinery so the drill is 100% perpendicular to the bracket.
I had to pay the guy 10 € for the job so maybe it's worth asking a frame builder near you?
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• #118555
Cool, I'll have a look around
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• #118556
You need the proper machinery
All cuts are easy once you have the cutter and the workpiece securely held in the correct relationship with one another 🙂
The trick with boring the guts out of a BB shell is getting the frame solidly mounted down to the mill table with the BB axis parallel to the spindle. Frame builders have a head start because they are already 95% of the way to having the right jigs.
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• #118557
There's also the technique of getting one cup out (are you there yet?) then bashing the cartridge out with a hammer, then hacksawing the remaining cup into segments, then cold chiseling the segments out. It has been done!
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• #118558
Not yet, but that was my plan - I've drilled into it to try and get the bearings out to fit a hacksaw in to get the nds cup out to do the above... A complete waste of time but I don't want to just throw it out!
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• #118559
Is it a cartridge BB?
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• #118560
Also sawing a seatpost out of another frame, fun. In other projects - has anyone widened a brake bridge hole in an old steel frame to fit modern calipers? Is that the simplest/best solution?
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• #118561
Yep - think having it milled out may be the only real option now
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• #118562
I get what people are saying above about jigs etc. Buy if you use a smaller milling bit you've got more room for error if you've not got a perfect straight and steady line through the BB. IANAM (I am not a machinist).
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• #118563
Yeah that's what I was thinking. I keep putting it off because after 10 minutes I want to throw it through the window
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• #118564
has anyone widened a brake bridge hole in an old steel frame to fit modern calipers?
It's the leading face that needs to be widened and unless your frame has a particularly strange geo, you won't get a drill inside the triangle.
Have a look on Sheldon Brown, he covers fitting modern brakes to an old frame: I think it's in the dual pivot brakes article.
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• #118565
Gotcha, cheers!
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• #118566
The easiest way to do it is to use a front brake on the back as well, and just drill the fork out.
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• #118568
I used a regular cordless drill with a good HSS drill on my GF's mixte. Fork was easy and the rear bridge turned out pretty rough, but it works well enough.
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• #118569
just gona leave this here, work in progress... now for paint...
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• #118570
ooooft
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• #118571
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• #118572
Enjoy!
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• #118573
: D I have not yet ride it enough, but I find it well balanced for me : )
do I must I find it a flater stem to finish in Bike Porn ?
cheers Miro_o
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• #118574
Just an Italian one :)
I've been battling with The Most Stuck Bottom Bracket Ever on and off for a few months, tried all of the above including a 12" plumbing wrench and 6' scaff tube, blowtorching, soaking in penetrating oil... It even broke the tool at my LBS. Have now started attacking it with a drill and hacksaw as I'm stubborn - anyone have any experience of this?