Broke bolt extractor - what to do?

NuggyBuggy

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So was taking off the front wheel on my bike. The hex recess on one of the pinch bolts was rounded on the inside - not my doing.

What was my doing : I tried using a bolt extractor after soaking it in penetrating oil and heating a bit. Yup, the worst happened and the extractor itself snapped.

The head is recessed so I couldn’t get a grip on it. I know some advise cutting slots with a Dremel to fit a flathead in - but not sure how that would work with a rotary tool and so little space and the head recessed. I do not know how to weld.

What’s my next step?

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Dremel. Cut a slot very carefully to fit a flat for a hand impact. Tight fit is critical.
 
Ooof. How far in was the extractor when it broke? My first attack would be using a punch (and safety glasses) to try to shatter the extractor. If you can get extractor out, you can drill. I assume these are through holes and you can see the bottom of the bolt? I assume they are pinch bolts and the bottom part of the yoke doesn't drop off? Drilling it all out and cleaning the threads would not be high on my list of safe and fun activities.

It's going to be a prick to get cutters in there to make a slot. You may be able to start with a disc but very shortly after you'd need to switch to a burr. After you get a slot, I'd use an old school impact screwdriver (the kind you hit with a hammer) to break it free.

This guy has good luck with a diamond hole saw to clean out a broken tap. As with my first paragraph, popping the head gets you somewhere but you have a long way to go before the finish line.

 
Dremel. Cut a slot very carefully to fit a flat for a hand impact. Tight fit is critical.
Looks like I'm shopping for tools. Looking now for a hand impact. I had a Vessel but I lost it last year. Grr.

I have a crappy rotary tool and this set of accessories but have no idea what I ought to be using here. I see some burrs but as with all things Mastercraft, not sure how good they are. Think I'll take one of the other bolts and see how successful I am at cutting a slot - off the bike of course.
 
Looks like I'm shopping for tools. Looking now for a hand impact. I had a Vessel but I lost it last year. Grr.

I have a crappy rotary tool and this set of accessories but have no idea what I ought to be using here. I see some burrs but as with all things Mastercraft, not sure how good they are. Think I'll take one of the other bolts and see how successful I am at cutting a slot - off the bike of course.
I'm thinking more like a cutter and less like diamond or abrasive.

 
Just checked the assortment of discs I have. Smallest one is too big to get in there. I guess I could cut it smaller?
The first cut would have the shaft centred on the bolt to mark both sides of the slot. It will be very hard to to without nicking the fork leg. If you want a smaller disc, cut something to wear part of it away. As diameter decreases, you may need more speed to keep progress up.
 
So was taking off the front wheel on my bike. The hex recess on one of the pinch bolts was rounded on the inside - not my doing.

What was my doing : I tried using a bolt extractor after soaking it in penetrating oil and heating a bit. Yup, the worst happened and the extractor itself snapped.

The head is recessed so I couldn’t get a grip on it. I know some advise cutting slots with a Dremel to fit a flathead in - but not sure how that would work with a rotary tool and so little space and the head recessed. I do not know how to weld.

What’s my next step?

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Have you tried driving out the axle to allow tightening of the other bolt.
This will reduce the pressure on the one with the broken extractor.
Then tap the head of the problem bolt using a small chisel in counterclockwise direction.
If this fails grind off the head of the bolt with a ball shaped carbide burr.
Once the head of the bolt is removed the thread portion should be only finger tight.
1/4 inch air die grinder will work better than a 1/8 dremmel
Plan B
Using a hacksaw in the expansion slot in the lower fork to cut the bolt in half.
The head portion should just lift out and the threaded portion can be removed by drilling a hole for your extractor.
Use a drill the same size as the bolt to centre the the hole in the remaining thread portion and then use a smaller drill for the extractor.
 
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Is your first picture from before or after the extractor broke and stuck in it? I can't really see much, if any, of the extractor stuck in there.

I've shattered rotary cutoff discs trying to cut slots in similar recessed things, so dig out your safety glasses. Pretty sure I was trying to cut both sides of the slot at the same time, and the discs bind up easy doing that. Probably better to cut one side of the slot at a time with a smaller disc.

I can't weld worth a damn, but I do own a welder and I think I'd try that first. Hammer in an oversized torx bit, get a neighbor to tack weld the bit to the bolt head, and then go to town with an impact driver.
 
Is your first picture from before or after the extractor broke and stuck in it? I can't really see much, if any, of the extractor stuck in there.

I've shattered rotary cutoff discs trying to cut slots in similar recessed things, so dig out your safety glasses. Pretty sure I was trying to cut both sides of the slot at the same time, and the discs bind up easy doing that. Probably better to cut one side of the slot at a time with a smaller disc.

I can't weld worth a damn, but I do own a welder and I think I'd try that first. Hammer in an oversized torx bit, get a neighbor to tack weld the bit to the bolt head, and then go to town with an impact driver.
If you hammer/press in the torx, you probably don't need a welder. Welding bits to bolts doesn't normally work well. If the torx breaks off, now you have a bigger hard plug to deal with. Nuts are normally the winner. Sit it on top and fill head/inside of nut with weld. Tons of surface area, similar metals, external flats to grab on to and apply force, lots of heat put into bolt, all wins.
 
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Nuts are normally the winner. Sit it on top and fill head/inside of nut with weld. Tons of surface area, similar metals, external flats to grab on to and apply force, all wins.
That's a good point. I will file this away and hope that I remember it when it inevitably comes time that I need to use it.
 
I've been busy since my last post trying this and that, but sad to say, no better off.

Dremel. Cut a slot very carefully to fit a flat for a hand impact. Tight fit is critical.

I was able to cut a slot using a few burrs from my set. @GreyGhost is right, nearly impossible to do without nicking the surrounds, but that's fine. My bike has enough nicks already. Set it with more penetrating oil, then drove off to Whitby from Orillia because someone was selling a Vessel impact driver, the only other options I could find nearby were at CT and PA and I figured two of the bits it came with were probably JIS.

That Vessel is a frigging beast. Apparently, you need to wail on it and I'm too timid to do it within such confined quarters. One of the reviews I read (after my drive to Whitby) said he thought the springs were way too stiff. I suspect it's destroying the nut slowly, to be honest, and I don't see the thing budging.

EDIT: As I study it now - I'm not sure it's working properly. If I understand correctly, compressing the head against the body should cause the business end to rotate a few degrees. I don't think that's happening. Guess I should have saved the drive and gone to PA/CT.

EDIT #2: It is working properly. It's just that you have to put a TON of tension on it before hitting it. I had a different Vessel and it was nothing like this.

Then bought the two biggest slotted screwdrivers I could find. The big screwdrivers don't work. They cam out.

Have you tried driving out the axle to allow tightening of the other bolt.
This will reduce the pressure on the one with the broken extractor.
Then tap the head of the problem bolt using a small chisel in counterclockwise direction.
Do you mean drive out the axle from the other side? Wouldn't the stuck pinch bolt prevent this from being possible? I did whack it a little with a rubber mallet from the left side, but it doesn't seem to be moving and I wasn't sure if I should expect it to.

If this fails grind off the head of the bolt with a ball shaped carbide burr.
Once the head of the bolt is removed the thread portion should be only finger tight.
I think for me that would be a move of last resort - I'd be worried that grinding that off would be a point of no return.

I think you suggested maybe drilling out from the bottom? It is a through hole. Unfortunately, I don't have a good way to lift the front end yet. I have a fork lift stand, two rear paddock stands, but yet no stand that will work with my SSA. I have an Abba SkyLift but no fittings. That all leaves me on my back with not a lot of space to see if I am drilling straight. I guess if I used a right-handed drill from the bottom it might help loosen the fastener itself? Hmmm. The left-handed drill didn't help loosen as they sometimes do, but I didn't drill down even close to where the threads were ... so maybe?

Plan B
Using a hacksaw in the expansion slot in the lower fork to cut the bolt in half.
The head portion should just lift out and the threaded portion can be removed by drilling a hole for your extractor.
I like this idea! Unfortunately, the slot is too narrow for a blade to fit in. Just checked.

Is your first picture from before or after the extractor broke and stuck in it? I can't really see much, if any, of the extractor stuck in there.

After the extractor broke... you're right. It's impossible to see. It must have broke exactly flush. I know it's there, because there was a hole there before, and now there isn't....
 
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I like this idea! Unfortunately, the slot is too narrow for a blade to fit in. Just checked..
Did you try full size hacksaw blade or a mini blade? For bolts, the smaller blades work well. I think the blades cut a smaller kerf. I can measure tomorrow.

Link is example, CT has them too.

 
Drill it out from the back side. The front side is buggered. - if you stripped out an 8mm Allen, then broke an extractor - iI can’t see a slot and screwdriver being any more than a waste of time and some extra unnecessary damage.

Worst case is a heli coil or tapping threads one size up to repair.
 
I had a realization last night prompted by some posts here. I hadn't pulled the other fasteners free so I didn't know the fastener wasn't threaded all the way through. I'd been spraying penetrating oil from the top of the fastener, but that would require the oil to work its way under the head of the fastener, then down through more than half the body of the nut to get to where it needs to be. So now I've putting the penetrating oil through the slot where hopefully it will start off closer to where it needs to be. Of course, the narrowness of the slot makes it hard to get that much in there, but I'm hopeful.

Did you try full size hacksaw blade or a mini blade? For bolts, the smaller blades work well. I think the blades cut a smaller kerf. I can measure tomorrow.
It was a full size blade. I have had a mini hacksaw but I didn't remember the blade being noticeably thinner.... it makes sense. Maybe a jeweller's saw would work - I put a feeler gauge in, and I think the gap is more than .03". Don't think there's enough clearance for the frame, though.

I have a long shopping list today just for this screwup: new hand impact driver, 3 lb hammer, mini hacksaw.
EDIT: Added the Skylift fittings for this bike - I've futzed around too long not being able to use the stand trying to save $150. I still have a bunch of other bikes I could make fittings for, and they don't have SSAs so I can use my regular paddock stands.

Drill it out from the back side. The front side is buggered. - if you stripped out an 8mm Allen, then broke an extractor - iI can’t see a slot and screwdriver being any more than a waste of time and some extra unnecessary damage.

Worst case is a heli coil or tapping threads one size up to repair.
You might be right... problem there is right now I don't have a good way to get the front off the ground enough to get room to work with a drill.
 
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