Gee3

I stripped the bottle cage hex screws on my CF frame. The screws on my new BD frame were overly tightened and I jacked them up.

So my question is, can I use screw extractors to get a hex screw out? If so, does it matter what kind to use? Sears extractors link

The shape of the head is rounded so I can't grip it with a vise-grip, so that's out.

Thanks for your help in advanced!

DDYTDY

I never had to do this on a bike but,

I would drill into the head with a drill thats about the same diameter as the threaded part of the bolt, then tickle the remnant out. If its a new bike corrosion should not be a problem.

Getting the head off will free the stud. If you just try an extractor on it it may break in the bolt and then you'll have more headaches.


Someone else how's solved your problem may have a better plan.

ianjk

Al1943

It's a tricky job but I believe I would use a small drill and CAREFULLY drill through the center of the bolt and work out the remains or use an "easy out" extractor small enough to fit inside the newly drilled hole and back out the bolt. You need to use utmost care to not ruin the threads in the female side of the fitting. If you question your drilling skills it may be best to take it to a good bicycle shop mechanic.

Al

Applehead57

Don't forget about cutting a notch accross the screw. You might be able to use a screwdriver to extricate the screw.

roadfix

Carefully cut a slot on the hex bolt head using a dremel tool and use a screwdriver to unscrew.

Edit: oops....above poster already suggested this.

J T CUNNINGHAM

No matter what you do in way of removal, protect the tube with cover padding FIRST.

Regards,
J T

Jim Bushard

ianjk you wouldn't be related th Reg Green would you?

tellyho

Drill out the head. Did it with my cleats. Use oil to lube and a high speed bit that's just a little larger than the opening of the hex part. Get an extra bit in case you break yours.

MudPie

I assume you mean the hex screw is an "Allen" style screw with a hex recess, and the hex recess feature is damaged. If so, I like this type of extractor since no pilot hole need to be drilled. The sharp edges on the extractor digs into the damaged fastener head as you apply force and turn. These can be used with a drill in the reverse direction, however, I'd recommend using a tap handle for better control.

https://www.sears.com/shc/s/p_10153_1...crew+extractor

mtnbiker4791

the other thing you need to check for is that the rivnut is not spining also. if it is drilling out the screw is only part of the solution and an easy out wont help because you need to tighten the rivnut but with the screw still in there its almost imposible without drilling the riv nut out also and installing a new one. To drill the old one out drill the screw out first if possible and then use a spot weld cutting bit to take the top of the rivnut off and the rest will fall into the frame. Two choices after that one is to pull the BB and hope there is a hole into the shell from that tube unless its a seat tube mounted rivnut then thats easy pull the seatpost. If no hole in the bb and its a down tube mount some silicone caulking down into the hole left by the rivnut will glue the remaining piece in place o it doesnt rattle. then have a new rivnut installed.

busted knuckles

If it is an allen key socket, I have found a torx head to grip what is left of the wallowed out socket.

operator

Easy out.

Ex Pres 

torx or old hex wrench w/glue

DER MotorSports

Bob is correct - in our industry, we find that stripped socket heads can often be removed using Torx keys.

J T CUNNINGHAM

When all else fails,

use a die grinder (dremel?) with a wheel to bring the machine screw down to slightly above

the parent metal (the tube) afterwhich an abraisive point will remove the balance.

Do not abraid the parent metal. (tube)

Regards,
J T

Gee3

Well, my local hardware store only had some spiral screw extractors that req'd me to drill in the head of the allen head. So I followed the instructions and now I have a stuck bolt with a bigger round hole in it that still won't grip onto the extractor.

I may end up trying to use my die grinder to make a slot to try and screw it out. Or maybe I'll bite the bullet and bring it to my local LBS... I'm swaying towards the LBS because I'm afraid I'll damage it beyond repair.

If they have to drill out the bolt and the riv-nut can a new one be installed in a CF frame? Please tell me yes! I'm thinking worst-case scenario if it comes down to that.

Thanks for everyone's suggestions!

bhchdh 

I don't get the rounded head shape not allowing you to use vise grips. I generally only use vise grips when bolt heads are rounded off.

Deanster04

This has worked with a small drop of penetrating oil allowed to work over night. Sometimes you can use a star nut driver slightly oversized to grab the bolt enough to remove it. Good luck

awc380

Hate to be the one to mention it, but this is a bolt the OP's talking about, not a screw.

In all likelihood, anyway.

dcb

I'm guessing it is like a pan-head

Anyway, cut a slot in it with your dremel and take the biggest flathead screwdriver that will fit to it, with a lot of pressure on the but of the screwdriver and the vice grips on the screwdriver for extra torque if needed.


Or if it is holding something on that has any depth to it, remove any other bolts holding the thing on then grind the head off the errant bolt, remove the thing, and put the vice grips on the newley exposed shank.

joejack951

This is something often encountered working on older cars. What I've done, which has worked very well, is to drill the head off the bolt first using a bit about the same size as the threads. With the threads being 5mm, a 3/16" drill bit should do the trick (the minor diameter of the threads is about 4.2mm which is really all you need to cut through). Slowly drill thru the hex recess. When you hit the shank of the bolt, the head should pop off and likely get stuck on the drill bit. That was the easy part.

The next part is much easier if some of the bolt is sticking out of the threaded hole still. If some is, you can likely grab it with your fingers and turn it out. If not, you'll need to drill a hole in it and use an extractor to get the leftover piece out of the hole. This is easier with left handed drill bits but I've had success with right handed bits. The left handed bit will sometimes catch as you are drilling and turn the bolt out of the hole. Right handed drill bits will tend to do the opposite. Worst case, you'll need to flip your bike upside down and shake until the little piece falls out the seat tube after the right handed bit screws it all the way through, or just leave it in there.

Good luck.

Wordbiker

All good suggestions (minus the sawzall, but it was funny ), any of which can potentially resolve the issue.

This thread just reminds me that it's what you do when things aren't going so well that make you a mechanic. There's no teacher like hands-on experience. Best of luck with the extraction.

reckon

I use these: https://www.4grabit.com/Default.asp?bhcp=1

which are GREAT as long as it's not stuck super tight,.... if the screw/bolt/allen whatever is REALLY stuck in there try these:
https://www.northerntool.com/webapp/w..._390507_390507

which are the best extractors I have ever used, but $$$$$$$$$

now to the original poster, dude,..you NEED one of these:
https://buy1.snapon.com/catalog/item....re&dir=catalog

the easiest way to remove a stripped/broken fastener is not to strip it in the first place: you mentioned that you messed up several fasteners in a row, so I would HIGHLY recommend that you go get SOME kind of torque wrench: for bicycles I like a 1/4" drive digital, or beam wrench that reads in inch pounds.
and of course, using the right size/shape tool for the fastener in question is critical

messed up fasteners are what separates the amateur from the pro or seasoned wrenchy, and is my biggest pet peave about buying vintage rides: some wannabe do-it-your-selfer has usually FUBAR'd every fastener on the bicycle/motorcycle/car.

which is why I spent over $600 on quality screw extractors, taps and dies and I use them all the time.

Wordbiker

From what I gathered the OP could've stripped the heads while trying to remove the screws, in which case a torque wrench does little good. The fix for that is using a fresh set of hex wrenches or bits, not rounded-off old cheapos.