removal of Grade 8 bolt

Arrgh. Have what's left of a Grade 8 bolt,flush with a steel plate. Any
ideas how to get it out? Can't get to the back of it( it's flush too). 5/8"
bolt in 3/4" plate.
All ideas, short of dynamite, welcomed !
Jay
Reply to
j.b. miller
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Carefully centerpunch the bolt. Drill a hole through the bolt. Pound an Easyout into the bolt and remove. If the stub is not in a blind hole you may luck out and have the drill bit catch in the stub and screw it through the plate.
Rex the Wrench
j.b. miller wrote:
Reply to
Rex the Wrench
Easy-out extractors are the work of the devil. Better to simply drill the hole in the bolt up to the tap drill diameter, and then pick out the thread coil that's left over.
Jim
================================================== please reply to: JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com ==================================================
Reply to
jim rozen
Soak it in Kroil an do a few heat cycles then try an ezout or drill it out with a left hand drill very sharp and you might snag the thing and walk it out. You might try a center punch and hammer and walk it out too. The trick is to figure out why it is siezed and why it broke...fix that!
Reply to
Tom Gardner
|Arrgh. Have what's left of a Grade 8 bolt,flush with a steel plate. Any |ideas how to get it out? Can't get to the back of it( it's flush too). 5/8" |bolt in 3/4" plate. |All ideas, short of dynamite, welcomed ! |Jay
Carbide left-hand twist drill Rex in Fort Worth
Reply to
Rex B
Get a thinner than normal 5/8" (bolt size) nut, center it carefully, set a hot plug weld down the hole with a stick or MIG welder. Heat cycle will help loosen it. Use a big breaker bar. You might have to repeat a couple times but you aren't messing anything up by repeating.
j.b. miller wrote:
Reply to
Roy J
jim rozen jim snipped-for-privacy@newsguy.com
I'm with RextW. And with you.
But try the Ez first. You can also punch out many such. A prick punch that will bite on the edge of the bolt material, if hammered (sharp blow, then assess and try again, and again) in a counter-clockwise direction (RH thread), "may" back it out. FM (of limited mechanical vocabulary)
Reply to
Fdmorrison
They sure are.... Drilling to the minor diameter is the course of choice, but requires fairly tight precision to succeed. A 5/8" thread...doubtful it could be accurately drilled with a hand-held drill motor. Lots of rigidity needed here. More likely to hog it out beyond redemption. If he can get it on a drill press, maybe so. JR Dweller in the cellar
jim rozen wrote:
Reply to
JR North
Before we all postulate on the various extraction methods, let's find out WHY it's sheared off. Extractors are only useful for removing threaded sections which can turn easily in the hole. Break one off, and the G8 bolt will seam like butter compared to the situation you have now. If the fastener was seized, and sheared off trying to be removed-forget extracting. Ditto if it was over torqued to the shear point and snapped. JR Dweller in the cellar
"j.b. miller" wrote:
Reply to
JR North
JR North wrote: (clip)doubtful it could be accurately drilled with a hand-held drill motor (clip) ^^^^^^^^^^^^ I am not as pessimistic as you. I have done this, without the precision, and what happens is that when the hole reaches the threads on the near side, you will very likely get a thin easily removed shell of the former threads, which comes out by itself, or is easily removed with a pick.
Worst case scenario--you mess up the threads, so you make your final drill size a Helicoil bit, and go from there.
I also like the idea of welding on a thin nut. You might even try welding on a flat lever with a hole in it, and then using it as the removal tool. I would make the hole a tad smaller than the thread diameter, and countersink it for easier access by the welding rod.
BTW, do we know whether the thread is siezed? Maybe a Dremel type tool could be used to cut a screwdriver slot, and just walk it out.
Reply to
Leo Lichtman
What's the problem with welding another bolt to it? Maybe I missed something.
wws
Reply to
wws
Weld a nut on the end and back it out with air impact wrench
Reply to
Tony
When Junior got his first car, the rear plate was attached with sheet metal screws into a clip on speed nut in one hole and into the hole plug in another. He insisted that the twisted off 6mm bolt had to come out of the nut-sert, so I grabbed the trusty hand drill and a couple bits. Would you believe, first try the thread spiral wound onto the bit when I broke through and I didn't even need to clean up. Junior was properly impressed. Gerry :-)} London, Canada
Reply to
Gerald Miller
Easy outs are always worth a try, and I usually have success with them unless the bolt broke because it seized or bottomed out in the hole. If you're drilling the bolt anyway, might as well try the easy out - making sure not to twist so hard that it snaps.
One of the problems with easy outs is that they can expand the broken bolt. The trick here is not to start with a hole for the largest size easy out that will fit the bolt. Start with a smaller size first, so that the smaller hole and thicker sidewalls won't expand the broken piece. Tap it in gently - don't bang it in so hard that it wedges the bolt into the hole. If it slips, tap a little harder.
Snap On, I believe, sells or used to sell a set of easy outs that had straight non-tapered splines, claiming that they would cut when driven in but would not expand the bolt. Makes sense to me, but I never tried them.
John Martin
Reply to
JMartin957
wws wrote: What's the problem with welding another bolt to it? (clip) ^^^^^^^^^^^^ It would be very hard to butt the end of a bolt against the flush, broken end, and make the weld, without sticking it to the metal around it.
Reply to
Leo Lichtman
Doesn't the nut have a nice, big hole in the middle of it that you could use? :)
Reply to
Tom Lawrence
(slaps forehead) As soon as I pressed send....................
Reply to
wws
Think about it for a moment - how much precision is *really* needed?
The difference between the crests of the female threads, and the root of the male threads is what counts here, and that number is typically at least five thou. For a larger fastener like that it may be ten.
Then consider how much effective 'wall' can be broken out - if there were another ten thou of metal that had to be broken though to make the 'helicoil' of leftover threads unwind, that's a doable situation.
Finally, the reason most fasteners sieze in place is from rust. Rust makes the fastener *bigger*, rust has a larger volume than the steel that it used to be. So the bolt is oversized and that jams it in the threads. Relieve most of the radial force by hogging out the center of the bolt and often the remaining bit just unscrews.
Really all you need to do is get +/- 0.015 accuracy and the hole will work fine. I've done this hundreds of times over the years.
The real trouble happens when a drill snaps off in the fastener as it's being drilled. This sometimes occurs when it's a blind stud, and the drill breaks through into the pocket underneath. Using a larger than normal pilot drill size helps prevent that.
Then the ultimate CF is when the E-Z out snaps off in the bolt. Those things are brittle and hard. They also tend to cam the fastener open more, and bind it in harder.
Jim
================================================== please reply to: JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com ==================================================
Reply to
jim rozen
JMartin957 wrote: (clip) Snap On, I believe, sells or used to sell a set of easy outs that had straight non-tapered splines, claiming that they would cut when driven in but would not expand the bolt. Makes sense to me, but I never tried them. ^^^^^^^^^^^^^ I was lucky enough to find a set at a flea market once, or I could not have afforded them. They really work. Each size comes with its own drill bit, and a special nut, which slips over the spline, which gives you much better torque and less chance of slipping that the usual tapered easy-out. If you are really stuck, I would say the price would be worth it.
Reply to
Leo Lichtman
On 12 Dec 2003 07:24:52 GMT, snipped-for-privacy@aol.com (JMartin957) wrote something ......and in reply I say!:
I have had 3 failures with Ez_Outs (broken Ezouts) to one sucess (removed a stuck spark plug, which is hollow already)
There are cheaper ways. I paid good money for that set of EZouts.
Problem is, the advice given below sounds good. Don't allow the EZOut to be too big as it expands the bolt. But My usual problem is a broken EZout. Smaller would have broken even EZier.
Welding a nut to the flush end has worked for me. It has also NOT worked for me. Then sometimes it worked next time (cheaper than an EZOut and a trip to town) and sometimes it did not.
In the end, sometimes you drill the sucker out, mess up threads or not, and helicoil if needed.....
Or is simply seized in there GAP
**************************************************** sorry remove ns from my header address to reply via email
I was frightened by the idea of a conspricacy that was causing it all. But then I was terrified that maybe there was no plan, really. Is this unpleasant mess all a mistake?
Reply to
Old Nick

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