How to remove rounded out hex / allen screw?

Tinkerer

Senior Chief Petty Officer
Joined
Mar 15, 2003
Messages
760
Apart from the usual drill / ezy out (there's a laugh) / tap / heat methods, is there some nifty way of getting a hex / allen screw out when the hex hole has been rounded out and won't take the key? <br /><br />It's a recessed head, the top of which is flush with the part it's holding, so I can't get at it from anywhere except above.<br /><br />We're talking pretty tough steel on a mulcher blade.
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Re: How to remove rounded out hex / allen screw?

Got a welder? Weld a bolt to the top of the allen screw and then just wind it out normally.<br /><br />Chris........
 

Tinkerer

Senior Chief Petty Officer
Joined
Mar 15, 2003
Messages
760
Re: How to remove rounded out hex / allen screw?

Chris<br /><br />Thanks, but I've only got arc. The head is so small that any attempt to weld anything to it will probably just weld the head to the fitting it's holding as well.
 

RPJS

Lieutenant Commander
Joined
Jul 29, 2002
Messages
1,572
Re: How to remove rounded out hex / allen screw?

Get a good set of male "star drive" sockets, pick the one just up from the rounded out bolt and hammer it into the hole.
 

Link

Rear Admiral
Joined
Apr 13, 2003
Messages
4,221
Re: How to remove rounded out hex / allen screw?

Originally posted by RPJS:<br /> Get a good set of male "star drive" sockets, pick the one just up from the rounded out bolt and hammer it into the hole.
YUP waste of a star head (only 2 bucks) But I just did that last week and it worked.<br />And I thought it was my idea ;)
 

one more cast

Captain
Joined
May 6, 2002
Messages
3,143
Re: How to remove rounded out hex / allen screw?

Try a prk punch and a hammer.prk a dimple near the edge and then lean the punch so when you tap it it will turn the bolt. Note: prk= P R I C K
 

fixin

Senior Chief Petty Officer
Joined
Apr 23, 2004
Messages
775
Re: How to remove rounded out hex / allen screw?

Take a dremmel tool and cut a slot in it,then you can use a screwdriver to get it out.
 

Boomyal

Supreme Mariner
Joined
Aug 16, 2003
Messages
12,072
Re: How to remove rounded out hex / allen screw?

Originally posted by Fixin:<br /> Take a dremmel tool and cut a slot in it,then you can use a screwdriver to get it out.
Good idea Fixin, but it should be a carbide bit.
 

fixin

Senior Chief Petty Officer
Joined
Apr 23, 2004
Messages
775
Re: How to remove rounded out hex / allen screw?

Originally posted by Boomyal:<br />
Originally posted by Fixin:<br /> Take a dremmel tool and cut a slot in it,then you can use a screwdriver to get it out.
Good idea Fixin, but it should be a carbide bit.
I use the little cut off discs,just got to make sure you wear the safety glasses. :cool:
 

Nos4r2

Lieutenant Commander
Joined
Dec 12, 2004
Messages
1,533
Re: How to remove rounded out hex / allen screw?

If it's part siezed (and they usually are if the head's mullered)then the p r i c k punch and drift idea's the best. The hammering shocks the threads free quite nicely.
 

Boomyal

Supreme Mariner
Joined
Aug 16, 2003
Messages
12,072
Re: How to remove rounded out hex / allen screw?

Originally posted by Nos4r2:<br /> If it's part siezed (and they usually are if the head's mullered)then the p r i c k punch and drift idea's the best. The hammering shocks the threads free quite nicely.
Along those lines Nos4r2, he could cut the slot head in it then use an impact driver to try to jar it out.<br /><br />Tinkerer has been too busy makin nice to us Yanks :p so he never said what the fastener was stuck in. If it is aluuminium ;) he should apply some propane heat around the fastener before he goes a beatin on it.
 

BLU LUNCH

Lieutenant
Joined
Aug 8, 2003
Messages
1,316
Re: How to remove rounded out hex / allen screw?

I work for Allen it's part of Danaher we make millions of screws and bolts under the Holo-Krome name and Keys under the Allen and Craftsman names. Stripping out hex head product is caused by using a inferior over seas product. Our product is made so the tool fails first by heat treating the key to a lower hardness. I see the mechinics use the punch that heads the screws and the bolts hammered in and they use wrench to turn it out. Our made in the USA high performance fasteners are used by OMC, Harley-Davidson, Catapiller, Disneyland, Garrett Turbo's we also made the main turbo shaft,and we were proud to make the lug nuts and windshield bolts for Craig Breedlove's Sprit of America....
 

Skinnywater

Commander
Joined
Mar 7, 2002
Messages
2,065
Re: How to remove rounded out hex / allen screw?

Those inferior over seas hexhead used on Mercedes <br />Benz come out with a good smack with a drift centered on the head. Tap in the allen and remove. Tapping in torx bit is a good idea also.<br />If I feel one is going to strip, I'll always smack it with a drift first and lightly coat the bit with valve grinding paste and tap it in.
 

Nos4r2

Lieutenant Commander
Joined
Dec 12, 2004
Messages
1,533
Re: How to remove rounded out hex / allen screw?

hey Blu, wanna send me some free samples? :) :) :) <br /><br />We rarely see the genuine thing over here. The industry's largest supplier here doesn't even use the term "allen bolt", they just call them socket caps.
 

crab bait

Captain
Joined
Feb 5, 2002
Messages
3,831
Re: How to remove rounded out hex / allen screw?

mix up a LITTLE epoxy or marine tex putty..<br /><br />put a drop into the hex head carefully .. insert the hex key .. let cure for 36 hours
 

Tinkerer

Senior Chief Petty Officer
Joined
Mar 15, 2003
Messages
760
Re: How to remove rounded out hex / allen screw?

Originally posted by Boomyal:<br /> Tinkerer has been too busy makin nice to us Yanks :p so he never said what the fastener was stuck in. If it is aluuminium ;) he should apply some propane heat around the fastener before he goes a beatin on it.
Boomyal, you're too kind. And you went to the trouble of dispensing with that terrible aluminum word just for me! :D <br /><br />The allen screw holds a disc cutter on a $300 replacement value mulcher I picked up last week for $5 at a garage sale. <br /><br />The cutter is rotated as it blunts by releasing the allen screw and tightening it after rotating the cutter. <br /><br />I figure they're all some sort of special quality metal beyond mild steel to put up with the belting they get chewing up branches, so I'm wary of applying heat to release them in case it upsets the metal quality.<br /><br />I've discovered that the screws project slightly below the carrier disc. I think I'll soak them in rust destructor for a while and then try in order:<br /><br />Shock to free them<br />Cut screwdriver slots on projecting part of screws<br />Hit with impact driver<br /><br />After shattering the projecting part of the screw I will belt the bejasus out of the remaining stub with a big mash hammer and attack it from the hex hole side with the star bits.<br /><br />After ruining a few star bits I will then move on to cutting slots with the Dremel.<br /><br />After shattering the screw heads with the impact driver, I will then drill them out with cobalt bits.<br /><br />Or maybe I'll just drill them out and shorten my learning curve for a change.<br /><br />Thanks to everyone who posted. They're all good suggestions and most of them hadn't occurred to me in any form.
 

Johnshan1

Senior Chief Petty Officer
Joined
Apr 15, 2003
Messages
739
Re: How to remove rounded out hex / allen screw?

I took the next size up allen wrench, used a handheld grinder to "shrink" it a bit, then pounded it into the allen bolt with a hammer, works great. This was on a Garret Turbo on a Volvo 850 and rather hard to get at.
 

BLU LUNCH

Lieutenant
Joined
Aug 8, 2003
Messages
1,316
Re: How to remove rounded out hex / allen screw?

Johnshan1 that is the same idea as using the oversized punch from the header that makes the bolts and screws at work. The main shaft from your turbo is headed on the same machines as the bolts......
 
Top