So, I have been an idiot and over-tightened and snapped a bolt when trying to screw in a new bottle cage. Do you have any idea how I can get this out?
by bongoboyyy
So, I have been an idiot and over-tightened and snapped a bolt when trying to screw in a new bottle cage. Do you have any idea how I can get this out?
by bongoboyyy
11 Comments
Drill a small hole/indent, use a screw extractor
There are lots of ways none fun. You can cut a notch into the remaining screw and using a flat head unscrew it. You could also drill into the screw and using a screw extractor unscrew it and if its super loose you could try superglueing something to it and gently unscrewing it.
If all else fails and you cant get the bolt out, you can drill the head of the rivnut off and install a new rivnut. You’ll have to fish inside the frame and probably remove the BB to get the loose parts. Its going to be a bugger of a job as the remaining allen key is below the level of the frame. Good luck.
Drill/dremel off the rivnut, careful not to enlarge the hole in the frame, and fit a new one.
Left hand drill bits and extractors are made for this. Just take your time so you don’t mess up the threads on your bike. [here’s a set from harbor freight](https://www.harborfreight.com/screw-extractor-and-left-hand-drill-bit-combo-set-10-piece-63987.html)
Before you do absolutely anything involving a power tool, start off by soaking the broken bolt in PB Blaster overnight to make sure it’s nice and loose.
Once you’ve done that, get yourself a small, pointed punch (like a nail set), and a set of metal picks. For something small that isn’t corroded, 9/10 times you can (with patience!) manually tap tap tap and manipulate the bolt around enough to unscrew it enough to get a pair of vise grips on it.
Just be patient, and use small taps of the punch to literally rotate the bolt around.
I’d stay FAR away from screw extractors. If you have to drill it out, use a left hand drill bit. They cut in a CCW direction, so you run your drill in reverse, and as they cut into the bolt they also cause the bolt to spin out of it’s hole.
Just slow down, and take it easy. Stuff is only a little fucked right now. If you’re cool about it you can fix it with minimal tears. If you gorilla the fuck out of it things can go sideways fast.
Lots of people commenting on here about using a screw extractor and all that. While that can work I couldn’t get it to work for myself when this happened. I took it to a LBS and they extracted it for like $5-10 on the spot. It was a nice experience and there was no damage to the threads. I know this is a DYI sub mostly but sometimes it’s best to get things done by the pros. If you do try it just be really careful as to not make things worse.
You can also try to epoxy something onto that surface of the broken screw. Then grab that thing gently with pliers and turn the screw out.
Change all Trek frame screws with new ones. the stock ones on all Trek bikes are very soft and do not tolerate anything over 5nm. this happened to my Trek too. Reason the screws are this soft is to protect the aluminum frame and sacrifice the screws.
Im confused how the advice against screw extractors has this many upvotes. screw extractors used the right way are exactly for such cases. Do not make any hard impacts on the screw, it’s already a soft screw and you don’t want the threads or anything to get out of shape and rough which makes unscrewing it more difficult. Spray any penetrating lubricant, wait couple of hours and then start working on it.
Lefty losey righty tighty.
Before potentially fucking up your frame / paint; take it to your LBS and let them sort it out. They will already have the necessary tools needed and will probably cost less than you buying the tool itself.