Need Help To Remove A Bolt With Stripped Head

C

compact8

Registered
Registered
Joined
Oct 13, 2012
Messages
324
I thought I could do it but this is the result :

strip%2Bhead.jpg

The bolt is a M4 counter-sink socket-head. Before I screw it up further, I would like to seek advice from members of this forum. There are tools out there designed for extracting bolts or screws with stripped head but my impression is that they are for bolts of larger sizes so I don’t think they are the solution to my problem. I can drill out the head easily but doing so will leave the body of the bolt fully buried in the hole and I guess that will be a more difficult problem. The hole is a through hole.

May I have some suggestions pls ? Thanks in advance.
 
Where possible I normally will drill the screw out with a tap size drill, then just run a tap through it. You have to be careful that you get the started in the original threads, and as the bolt material breaks up that you don't jamb and break the tap. This technique usually works. A small pick is helpful to peel out the screw material. Sometimes I grind a very narrow chisel out of a broken tap to work around the edge to start the extraction process and expose the top threads so I can start the tap in the threads.

In this case it might be helpful to remove the top plate if possible, there may be enough screw material left to just grab it with vice grips. This would require drilling the screw head out.

It also may be possible to use a center punch and try to just unscrew the screw.
 
Center drill with a #40 or smaller bit, then drill for a #1 easy out. Make sure your total drilled depth is enough to allow the easy out to go deep enough to grab and not bottom out. Drilling the head off should be the last resort.
 
+2 on using a SHARP center punch(better yet,use a more acute angled prick punch). Punch around near the edge of the head to start loosening the bolt. It looks large enough to get some decent leverage by punching the head.

Try to keep far enough from the edge of the head so you don't increase the diameter of the head,and add to jamming it tighter by making it tight in the counterbored hole.
 
Echo,

i'll take a Center Punch, Diamond Point Chisel, or Cold Chisel and hold it on the bolt head near the center hole but not in the hole.
give a sharp smack with a hammer in the loosening direction.
the result will leave an indentation in the bolt head as well as adding shock to the equation.
i'll beat the bolt head into submission until turns, usually 3 or 4 good whacks will do, or many small whacks seem to work too on smaller fasteners.

if this should fail, i'd break out the drill and drill a 5/32" hole in the center to break the head off, then extract the other piece.
 
I would also give it a little heat. It doesn't look corroded so if you have had that much trouble getting it out there is the possibility it was assembled with some type of thread lock. You may need heat or an impact/shock to break the seal.
 
First Off.....Is this stuck because the center stripped out ? If so, I have gotten screws out by using a sharp center punch and tapping the head of the screw in a counter clockwise direction. The punch will dig in and the tapping can sometimes shock the screw loose. Just like Ulma Doctor suggested. It usually works well. If that does not work I will try an easy out. If that then does not work I will try drilling in the center with the tap drill and pick out what I can before using a tap to clean up the rest. If all that fails I will drill for a Heli-coil and install.
 
From the looks of it if you were to drill the head of the screw off you would be able to remove the top plate, this should leave enough of the screw exposed to get a good grip on with vise grips. With the head drilled off and the top plate removed there will be no tension on the screw holding it in place and it should back out easily with the vise grips (possibly with just your fingers). For drilling the head off the screw I would use a M4 drill bit and drill slowly, when you reach a depth that the drill would be entering the body of the screw the head will simply separate, stop drilling there and remove the top plate.
 
Try a left hand drill bit. Sometimes they will lock up and back the screw out. If nothing else it will drill the head off then you can back to shank out with a pair of vice grips.

Sent from somewhere in East Texas JP
 
All above comments are good ones. I have also had very good luck TIG welding a piece of material onto the part to be removed. And I guess the heat from the TIG weld also helps. Depending on size, the weld could be smaller than you are used to. But it can be done. Just a little more patience with the current control and a close-up lens in your hood are good things to note…Good Luck, Dave.
 
You must log in or register to reply here.
Back
Top