Quantcast

Suggestions for getting a stripped bolt out

mtbpaint1

Monkey
Apr 25, 2005
326
0
University of Connecticut
Bolt on the side of my stem is stripped, i desperately need to get the crowns off so i can put another fork on so i can bleed my front brake, because the rest of my 888 (only sent in the stantions and lowers) is being fixed after my incident at Mount Snow. So i need to get the bolt out whats some easy in home ways i can do this

Note-brought it into my LBS (VERNON CYCLE for all you CT people) and they "had no idea" how to get it out
 

johnbrittain

Monkey
Jun 14, 2003
200
0
Amarillo, Texas
if the bolt head sticks out a bit further than thesurface of the stem, then you could dremmel it and use a flathead screwdriver, and if the bolt is flush witht he stem or is sunk in a bit then use a hacksaw/dremmel to cut the bolt in half where the stem has that cut in it so it can tighten around the steertube, and then you will at least have the stem off, and getting the bolt out from there should be a ton easier. 'hope that wasnt TOO confusing...
 

ncrider

Turbo Monkey
Aug 15, 2004
1,564
0
Los Angeles
If you don't have a hacksaw or dremmel then try the ghetto fix. I'm asuming you striped the allen key hole, to ghetto fix it take a screw driver head (I have a set of flat head bits that I've used for this), Place the flat head into the hole so that it goes into opposite corners (use a bit that is just wider than the hole). Now pound it into the hole. It will eventually dig into the corners deep enough for you to use the flat head bit to unscrew the bolt.

It's super ghetto, but works.
 

Taro

Chimp
OK , if the ex key hole is broken , go to sears and get a kit for strip screws and use the right size one to unscrew the bolt by fitting it in the strip hole . If you broke the head all together , you'll have to make a smaller then the bolt size hole in the bolt and use a extractor , it looks like a strange bit with long teeth that you punch into the hole you made in the bolt and you turn counterclock wise . If it doesn't work , find a machine shop and they do it for you . Be carefull , if you're not feeling like you can do this don't try and take it to the shop . If you mess it up you'll have to buy a new stem .
 

D_D

Monkey
Dec 16, 2001
392
0
UK
Sometimes you can use a torx bit. Similar to the flat head screwdrive but with more contact points.
Smack the closest fitting bit in with a hammer and twist.
 

T0mo

Monkey
Feb 12, 2003
434
0
nedtown, colorado
johnbrittain said:
if the bolt head sticks out a bit further than thesurface of the stem, then you could dremmel it and use a flathead screwdriver
I've done that a bunch of times and it's always worked great. You don't even need to replace the bolt after it's done.
 

Brian HCM#1

MMMMMMMMM BEER!!!!!!!!!!
Sep 7, 2001
32,119
378
Bay Area, California
What also sometimes works is use a US standard wrench set, they are a hair larger than metric and you can tap the standard wrench in with a hammer then try to loosen. It's worked for me several times, try that first before hacking up the bolt head.
 

ALEXIS_DH

Tirelessly Awesome
Jan 30, 2003
6,147
796
Lima, Peru, Peru
there is this tool, which is like a screw, but its threaded in the opposite direction of the regular threads...
get a nail and hammer a little dimple in the middle of that bolt, big enough so that it can be the guide for the other tool-screw...

then put that screw, and as you turn counterclock wise, it will carve itself into the metal, and un-screw the stripped bolt out..

i dont know how is that screw-tool called in english, but am almost certain you can find it in any big hardware store.... and it shouldnt be that expensive..

just get the right size (which is about 1/2 the width of the bolt's thread at the widest point) if you dont get the whole set.
 

Matt D

Monkey
Mar 19, 2002
996
0
charlottesville, va
I've tried the EZ outs w/o success, they just snapped when I applied some force. I like the flathead screwdriver method, but if none of the other methods suggested work, you can simply drill the bolt out. To do this, first start by drilling off the head of the bolt, which will pop right out. After thats off, you'll just have the threads remaining. You want start with a small bit and start a pilot hole, then work your way up in size until you're almost to the size of the bolt. The big thing is to be careful not to bugger up the threads, but you need to get close enough where you can just pick away the remaining pieces of bolt that you couldn't drill out.

Hope that makes sense. I do this all the time with cleats on shoes, and use it as a last resort for bike parts.
 

ALEXIS_DH

Tirelessly Awesome
Jan 30, 2003
6,147
796
Lima, Peru, Peru
mtbpaint1 said:
tried that screw thing two days ago...didnt work. Maybe we need a more powerful drill
hmmm... might be something not working right there...
are you sure you are using the right tools??

get a drill, and you have to drill in depth about 2-3 times the width of the hole's width.

i dont have the exact formulas at hand, but for a UNC screw (i assume you are trying to get out an english bolt with regular threads), the hole you have to drill is about 1/2 the nominal bolt size at the widest point in the thread...

if its a UNF (english fine thread), then you have a bit more clearance... but to be safe drill a hole about 1/2 the thread width.
be sure to meassure the width of the threaded part, NOT THE HEAD to decide what size of hole you need to drill...

you dont want to drill a hole too wide, because you will mess up everything...

drill about 1-1.5 times the bolt width, deep... and that should be enough to grip and take out the bolt..

be sure to use some loosening liquid too..
 

sanjuro

Tube Smuggler
Sep 13, 2004
17,373
0
SF
Can you post a picture? I know some mechanics in the area, and they might have a solution if they could look at the picture first.
 

shocktower

Monkey
Sep 7, 2001
622
0
Molalla Oregon
Drill the screw out at about 40% of it`s size put and EZ-out in the hole you will remove the scew :thumb: :thumb: :thumb: ,and if you don`t know what an EZ out is go to a Hard ware stor and as they will tell which isle


BTW Love bunny loosening lube is called astro glide ;) ;) ;) ;) ;) ;)
 

BAXTER

Monkey
Jun 25, 2005
161
0
THE BURG but missing BOSTON
Oh yeah, after the head is gone, use superglue or another bonding agent to attach the end of a flathead screw driver to what is left. If your threads aren't boogered up the rest should just thread right out. I 've done this AT LEAST 50 times . Mostly on Diabolis stems. Remember to grease the threads on your new bolts and don't over tighten.
 

Spunger

Git yer dumb questions here
Feb 19, 2003
2,257
0
805
I just had this happen to a rotor bolt, head snapped off. I used the dremel to cut a slot into it and worked it out with a flat blade screwdriver. That was for a broken bolt that is above the threads. If it was below you'd have to use a bolt extractor or screw extractor. I wanna say it drills into the middle and as you back it out it removes the broken bolt/screw.

Good luck though. It's frustrating but not as hard as it seems once you get the right tools and such.