Chris!

So I was moving a fear rack from one bike to another. When tightening the last bolt down the head broke. So I decided that I would use a drill and try to drill it out good or bad it what I tried. Well the drill bit broke. So I quietly put the bike in tha garage and went about my day. Hoping I can get it all out and retap the threads. It's an aluminum frame bike.

Russ Roth

Is the bit broken off inside the bolt to where its in the way? If not get a reverse direction drill bit and try again. If so try to get a tiny pair of needle nose and see if you can get enough of a grip to turn the fragment counter clockwise which may unstick it. In not tapping the bit with a center punch may work it loose. can also try epoxying something to the whole of the bolt and getting it to turn.

Gresp15C

A picture might help folks brainstorm on some ideas.

Chris!

I'll pop a pic up tomorrow. I just had to walk away when it happened. It's a new bike has not even been ridden yet.

Maelochs

I'd be really careful about epoxying an extension .... I mean, nothing could go wrong there, right?

Best bet is to buy a quality drill bit smaller than the screw, and to drill Very slowly. The screw/bolt/whatever might be stainless and very hard. Slip off you might gouge the frame .... push too hard you could break another bit.

You shouldn't need to retap the threads---if you drill out the bolt with a bit smaller than the bolt, you should be able to pull out the old bits and re-use the hole .... but re-tapping aluminum is not that hard .... but please be careful there, too.

I am glad you walked away ... I have failed to walk away on occasion .... it is like trying to dig your way out of a hole. As it stands, you are not really out much but the cost of a drill bit.

tomato coupe

Find a friendly machine shop and ask them to do it. Not only will they have the right tools to remove the screw, they'll be able to set it up so the frame suffers no damage.

indyfabz

+1. Sometimes is best to consult a professional. That's what I did when I broke a tap inside the barrel portion of a custom rear rack 3 weeks before the start of a long tour. Guy didn't even have to drill it out. He simply suggested flipping it upside down and starting over. I then let him do the drilling and tapping. Cost me maybe $15 back in 1999.

Just hope this doesn't spawn a "My LMS (Local Machine Shop) sucks!" thread.

Wilfred Laurier

Generally, drilling a bolt is only necessary to remove the head of the bolt, then a pair of pliers or vise grips can be used to unscrew the extending piece of shank.

If the shank doesn't want to unscrew easily then something else is wrong. Are you sure this was a metric (probably M5) bolt? There are imperial sizes that are close to the metric size but will not smoothly screw in or out.

Chris!

Pic if bolt

dedhed

Is the drill bit still in there? Drills and taps are generally hard but brittle and can usually be broken up with a punch and the pieces picked out.

Chris!

I was able to break the bit out and what I believe is most of the bolt. I think I'll drop it at my LBS and have them tap it for me. They are great guys and reasonably priced. Glad I walked away and didnt make it worse up front. I'll post results

bluehills3149

The easiest way to repair is to tap it out to a size bigger thread but this may cause issues when you attach things as the larger screw will necessitate making the rack hole larger. The best solution is a helicoil which is a steel threaded insert that will match the original thread. If it were me I'd insist on the helicoil method but bike shops may not have the tools.
Note you can buy a helicoil kit on amazon from $10up which includes the drill, tap and multiple helicoils.

Atlas Shrugged

If the threads are damaged in this instance you can also use Locktite Thread Repair compound which is not too expensive. Then run the bolt all the way through the rack mount and place a lock bolt on the other end. That won't be going anywhere.

Moe Zhoost

Those rack mount studs have through holes so you may be able to attack the screw from the back side. I'd try a conventional right-hand drill bit smaller than the threaded portion and hope that once it "catches" in the soft metal of the broken bolt it would turn it out. Use a new bit so it will "bite" well.

mstateglfr 

1- what is a fear rack?
2- screw/bolt extractors are a few dollars at the hardware store. The threading is opposite, so the tool digs into the broken bolt and the broken bolt unthreads out. Just an fyi for next time.

Korina

Good luck Chris!

Jicafold

It's a gear rack. F and G are next to each other on the keyboard.

You could just drill the whole thing out...forget the threads...and put a bolt all the way through and a nut on the other side.

washed up

It keeps people off his wheel.

Wilfred Laurier

It's obviously a Dear rack. Not sure if that means it is precious to the OP, or that it is expensive.

rumrunn6

one of my favorite topics!



be sure to report back!

Chris!

Could not get it out. Good thing my local shop had this 8.99 fix.

Wilfred Laurier

How did that bolt break, anyhow?

Also, you should shorten and/or put an 'acorn nut' on the end of the bolt holding the bracket on, if you like the skin on the inside of your thighs intact.

Wilfred Laurier

Another, less ugly solution, would be to use a single front rack stay (iff possible with your rack) and bolt it to the hole int eh brake bridge that has a plastic plug in it.

Chris!

I live in an area that uses a lot of road salt and my assumption is that the bolt was weak from that.... anywho it actually works out fine as long as it holds. And yes I do need to cap that bot off but they didn't have anying at the shop.

Miele Man

It looks like you were able to drill quite a bit of that broken bolt out. I'd try drilling the through the full length of that broken bolt and try an Easy Out or other brand broken bolt/screw extractor.

As another poster said, shorten that protruding bolt and/or add something to the end of it so it doesn't slice your inner thigh.

Cheers