JayKay3000

Hi all.

So I forgot to use some oil when putting a bolt into on of the bolts holes on my front forks to fit the front rack.

I think I must have put it in crossthreaded and thought the bolt might even out and re-cut some new threads.

Uh - No.

The end of the bolt came off.

I have about 3mm of bolt showing and I was using a lot of force when I was trying to put it in so it's stuck.

Not really having any experience of this issue I've probably made it worse by trying a few things. There isn't much room to get a big clamp on it.

My failed ideas:

> Screwing a bolt in from the other side in hopes of the contact unscrewing the stuck bolt
> Using a set of pliers to grip onto the exposed end and undo the bolt
> Using a bigger set of pliers to grip onto the exposed end and undo the bolt
> Cutting a small line into the exposed bolt to try and use a screwdriver to undo the bolt (Line not big enough from tool, screwdriver too small, bent screwdriver head)

There are no threads left on the small sticking out bit and the bolt is slightly deformed from my failed extraction attempts.

I'm taking it to a LBS in 2 weeks, but wondering if I can do this myself in the meantime - It was a brand new frame so I'm trying not to completely trash it before its done any real work.

I only have a basic level of hand tools and no workshop.

My main issue is the cost and trashing the forks - I don't want to spend the cost of a new set of forks by trying to fix the problem because then I could have just brought the new set of forks and sold the others as spares for cheap.

Side note - I bent another bolt from the same batch even when using lubricants so maybe I just got unlucky with a bad batch - I noticed this new issue and got the bolt out and successfully put a new one in its place without issue.

JoeTBM 

Or maybe you have the wrong bolt thread.

You do not say what size bolt or have provided a picture or the situation

Without a picture, it would be hard to save if an "easy-out" would work or your other choice is to drill it out and re-tap the hole.

dsbrantjr

Try drilling it out from the backside with progressively-larger bits. If you are fortunate at some point it will be driven out by the bit, otherwise you could attempt to re-tap it, again starting from the backside, but be aware that many bolts are quite hard and difficult to tap without breaking the tool off in the hole.
Going forward do not try to use a bolt as a tap.

andrewclaus

At this point, good shop tools and experience are needed. If it were mine and I needed it fixed right away with basic tools, I'd drill it out and retap to the next size. That may also mean drilling out the rack. Everything would be weaker.

grizzly59

If you can find a left hand drill bit I would give that a try. Old fashioned hardware store may have them. Hope your bolt is soft steel. Use penetrating oil for a few days prior.

sch

Although drilling it out is the usual approach, in practice this is a dicey thing since the drill bit will be just as likely to
wander off and drill something else on the fork even if the part of the bolt to be drilled is meticulously flattened with a
file and center punched with a fine point punch. Access from the other side would be ideal but limited by the other
side of the fork. Since the bolt appears to at least be cross threaded in a high torque scenario and made of soft
steel removal should be done by those experienced in such in view of your non-success even with a good bit of the
bolt protruding. If drilling is contemplated a center drill is much more rigid than a twist drill.

Community college machining programs are sometimes helpful to walkins with simple problems but in the time
of covid that option is foreclosed and hopefully you are not in a deep blue state where bike shops are closed as well.

dedhed

3mm sticking out? Try a vice grips

bldegle2

Without a picture.....your gonna get a lot of suggestions...drilling out carefully is the way to go. If you drill carefully with progressively larger drill bits after the first drill makes it all the way through and get the leftover bolt material to a minimum, you can use a tool of choice, chisel, screwdriver, punch, whatever, and 'collapse' the remaining material to the center. Once you do this, removal is usually bing bang boom....then you got to chase the threads before rebolting...

pdlamb

I'm batting about .500 using an easy-out. I'm worse than an American League pitcher trying to drill a screw out.

If you're not confident in your tool and machine skills, wait and let the bike shop deal with it.

Phil_gretz

Interestingly and not unrelated to the thread, I just watch a YouTube video that compared six or seven "easy out" systems for their hardness and effectiveness in backing out highly torqued test bolts. It was eye opening. The kits cost between <$10 (China) to over $60 (German). The higher priced kits had better hardness and worked up to higher torque values.

The Irwin basic kit was the superior low-cost option.



Of course, you have to supply your own drill bit(s) and machine oil, wrench head, etc.

I have a set of Craftsman left-handed chisel-head extractors that I've only had 50-50 success with. I don't recommend. They worked on a head cover bolt that sheared off on my 1967 Mustang, though. Years ago...

dsbrantjr

Well, the OP states they have access to the far side so left-hand bits are not needed. I agree that the best course would be to have a pro look at it.
If it is a very valuable fork it might be worthwhile to take it to a machine shop which has wire EDM capability and have the stub taken out in that way.

WizardOfBoz

It probably is going to be easiest to back it out. If the bolt is plain old steel and not Ti or stainless, one option is to weld a new head on. Works if have enough of the bolt sticking out on the side you broke off. On that side, can you put a little hex nut on the stub? If you can, you'd be well served to find a welding shop to weld that hex nut to the bolt. If the bolt is broken off flush or sunk, then you could try to drill it out. If it were me, I'd want to center punch a starting depression in the exact center of the stub, and then get the fork in a rigid fixture of some kind, and use a drill press. Pretty imperative to have that center punch divot to start the hold.

If the bolt is broken at an angle, so that a drill would be deflected away from center into the frame, take the thing to a machine shop and ask them to wire EDM the broken stud out.

Once out, CAREFULLY chase the threads with an appropriate sized tap (if you think getting a steel bolt stub out was hard, try getting a carbide tap stub out!) and test to make sure that the threads are not now too loose. If so, use a backing bolt when you install your rack again.

JayKay3000

I looked at prices for a replacement fork - they cost about $150 - luckily because corona I don't need the front rack at the moment.

None of these ideas sound that nice and probably a bit out of my skill range, but I think you're all thinking along the same lines as I am so I guess i'll take it to the experts as I've had a few more goes and progressively made it worse.

Thanks for your ideas though.

mikeread

If you can get round the back with a drill then try the following.

Take a new bolt and drill a hole through the centre. I would do this on a lathe but you will have to do the best you can without to get the hole central. Shortening the bolt will help.

Screw this bolt into the other side of the hole and use it as a drill guide to drill through the stuck bolt. Increase the drill size until the bolt comes loose or gets so thin you can pick it out.

Take care not to damage the existing thread, the more central your hole the better.

wsteve464

Spend a few bucks on some penetrating oil and a new pair of vice grips let the oil soak over night and clamp the vice grips on as tight as you can.

When resolved buy a set of taps to chase the threads before installing bolts.

One more edit you should be able to put the bolt most of the way in with your fingers