Soooooo I’ve just had my Bronson resprayed by the fantastic fatcreations and its immaculate and I’m rebuilding it ready for invisiframe and to continue.

Installing brand new bearings/axle kit etc and assembling as per instructions to 90 in lbs for the smallest bolt and due to the high toruqe settings and the fact suddenly my B********D torque wrench stopped working the bolt head snapped off with a ping.

Its now stuck solid with no clear way to remove.

Those up with Bronson and Santa Cruz axles will know how they work. The bolt hasn’t snapped low enough to allow me to remove the axle with the normal allen key. I’ve tried a flat bladed screwdriver on the other side of the axle to undo it and remove it. The shaft of the bolt is too narrow to tap a slot into to remove. The slots in the axle are too fine to use to remove the axle, the only option I can see is to drill out the bolt with as fine a drill bit as i can find (in my dremel kit most likely) and increase the gauge until the bolt gives way.

Can anybody else think of any bright ideas other than cry a lot and sulk, which I’ve admittedly managed to do all day!

Drill into it a little and then try a reverse threaded screw. As it digs in it should start turning the snapped bolt.

Don’t have a mental picture of the failure, but would an extractor bit work?

I’d look at an appropriately sized one of these http://www.screwfix.com/p/screw-extractor-5-piece-set/18643 and the smallest hole you can get away with – less chance of the drill bit breakign out the stud into the frame that way.

This small bolt threads into the axle which then threads into the frame so it would take a catastrophic failure for it to go right through into the frame. I’m of the mind that an extractor wont work due to the size of the thread shaft thqts left and the limited view of them.

if you have a good tool shop near by something like cromwells, Irwin make left hand drill bits along with the extractor but you normally find as you start to drill in reverse when the drill starts to cut it starts to pull out the broken stud so theres normally no need to use the extractor never had a problem using them on bolts which have been torqued a lot higher and thread locked

what middleagedmadness said really – if the head’s snapped off there’s no ‘load’ or tension on the bolt other than the friction within the threads so it’ll turn fairly easily once you can get purchase on it.

If its the axle that screws in from one side, I’m assuming that the wedge isn’t stuck in the end of the axle, meaning that the axle is only nipped up and not locked in place? The snapped bolt shouldn’t be under any pressure so once you’ve per-cured a bit of a grip its should simply unscrew

This one – http://89.234.25.113/jungleproducts/store/products/medium/1460396675_793_1.jpg

Is there anyway you can use a knife blade in one of the axle slots??

I’d also be trying to insert all nature of things into the opposite end of the axle. Small scissors, Torx bit, a tapered screwdriver. Actually I think this is the best option, you must have something in the house/garage? I’ve got a Heckler axle in front of me and I can wedge in a tea spoon handle and I reckon that will be enough purchase once wedged in to unscrew it from the opposite side. I know the Bronson axle is threaded on the opposite side so might mean trashing the axle

Good luck

GolfChick – I see your point on the extractor bolt as the snapped bolt is only about 4mm, so you’d need a 2mm.

I’d be very careful with any bolt extractor as of it breaks off in the bolt you’re really in the shit…

Carlos yes you’ve got the design right on the head. The tapered washer isn’t stuck so in theory there’s no real tension other than the medium strength loctite. The opposite side is a good idea but one we’ve tried, the material the axle is made out of is just way too soft as soon as you try to put any real strength through it you just slip through it like a soft cheese. Even though the axle is brand new at this point I just want it out whether I need a whole new £45 axle kit or not!

I think trying to find an opposite drill bit may be a good shout if there’s one small enough to still have the same effect

you can get the left hand bits from 1mm up , if your axle is 4mm id start with 1mm to get a pilot dead center then if it dont budge put a 3mm through it use the slowest setting on your drill so the bit dont snag and snap , try and get a decent bit though either cobalt or with a cobalt coating it makes life much easier

The opposite side is a good idea but one we’ve tried, the material the axle is made out of is just way too soft as soon as you try to put any real strength through it you just slip through it like a soft cheese.

Have you managed to remove the locking collet before you tried to undo the axle from the opposite side?

Can you get a pillar drill on its lowest speed on the other side of the bolt? That way the act of drilling it out is trying to unscrew it at the same time, no need to buy reverse threaded bits either.

The locking collet came off with the bolt head so no problem there.

Sobriety you had the same thought I just had while walking the dog. I have some lock smiths screwdriver bits that may be different enough to bite or even try to slowly drill it out as you said.

With the angled top of the bolt shaft left I really don’t fancy my chances of drilling dead centre in order to opposite drill the bolt back out. If it was flat with surface maybe but the fact it’s reccessed back doesn’t fill me with confidence.

OK.
If the locking collet is out of the way try jamming a couple of screwdrivers down either side of the bolt into the allen key hole. Then use a bar between the screwdrivers to turn the axle out.
Also get a hairdryer on the frame where the axle threads are and get it warm.

We did a snapped off bolt in some engine cases a few weeks back in the pillar drill. It had resisted all efforts while it was still in the motobike, so while the engine was being rebuilt we thought we’d give it a go.

Took about 20 minutes, and most of that was making sure everything was square, and checking it again, and once more to be certain. Started on a tiny drill bit, worked up to the largest size we could without damaging the threads, put the ez-out in and as soon as it bit it just wound the bolt out.

The key is taking your time(!), and being able to apply constant pressure on a dead straight drill. As you drill it, it heats up too, which helps things free off as well.

Whatever method you go for, if it has loctite on the threads warm it up first with a hair dryer or similar to soften the loctite, we use this at work when removing the anti tamper shear bolts from ECU housings

I’m pretty sure this will work.

You need to get a long bolt with the same thread as the end cap side (not the snapped bolt side). Screw it in and keep screwing, as long as it’s long enough it should lock in the axle against the inside bit of the snapped bolt then as you keep turning, it should unscrew it, no??

Won’t damage the frame as it’s only locked up against the inside of the axle

I hope that all makes sense

I have thought about this before posting and can’t see any faults in it, but I’ll happily be corrected

Carllos

Would heating it help, within a sensible limit? Assuming steel bolt in ally, the ally should expand more, and any threadlock may soften.

I’m pretty sure this will work.

I’m not.

Unless there’s a lot of friction between the two ends it’ll be like trying to turn a worm gear with the driven gear. You’re trying to unscrew something by pushing it really hard. It’ll just bind, like twisting two nuts together on a bold.

I did similar on an old bike i used to have, i just drilled the other side of the bolt through the axle and once the drill bit started to grip it just spun it out with ease.

The problem with this particular axle is that it’s the smaller version and as such isn’t really hollow. It has a domed surface instead so you can’t see through it I like the others.

Kinda doesn’t help you, but on my Tallboy 2 CC, the torque for the axle inner bolt is only 50 in-lbs on mine – 5.6NM for those that think that inch-lbs is the most stupid unit of measure ever created. Seems amazing that the Bronson would have such a different torque rating when the axle assemblies are so similar.

As others have said, if this is the tapered bolt into the axle, then drill it out with a reverse-threaded extracting bit, destroying the axle if needed. They are pretty cheap (and actually wear out anyway) so you shouldn’t feel too much pain.

as per instructions to 90 in lbs

Ah yes, the Santa Cruz torque specs. I did the same and snapped mine on my old Nomad using a torque wrench to the exact spec. Contacted Jungle about it and they laughed at the torque specs, said they’re probably a bit high, and sent me some free bolts.

Have been told that thread lock messes with the torque as well, and I was using a different spec of thread lock to the typical. I trusted the wrench and thought it should have clicked by now, but no and snap!

Anyway, bolt extractor but you may need to drill a pilot hole first. You may need HSS drill bit. If you’ve got stainless steel bolts that SC used to use (as mine had) then it’s even tougher. I used cobalt drill bit to get enough of a hole (using coolant as I drilled) and then the bolt extractor would fit. I just got a set of extractors with various sizes. Been useful for a number of things since, including removing old DU bushings 😀

I’ve had some success with left handed drill bits, i think i got them on ebay. Since you usually have to drill a pilot for an extractor, theres no harm in trying 🙂

I cannot help with the extraction but have sheared several using a torque wrench and now put a new one in each time. Guess I have been lucky getting the bolt out. I use lower torque now as well. Good luck

Drill it insert Lh roll thread tap then insert lh thhread bolt and out it comes

One of those broken head removal things they are a double edged sword too big and as they screw in they expand the bolt wall, and it also depends on broken below the hole top and material , soft materials deform more easily sometimes the net result is you make it worse sometimes if the twin god of bolt removal are smiling on you it comes out

Other method take to local spark eroders and give man beer money should take 20 minites

Thanks for the frankly superb ideas and sensible replies when needed!! Got it out by some miracle this morning. Combination of grinding the top of what was left down a little, using some heat and an Allen key with no angle at the tip meant it came out. Luckily only one small scratch and a small patch where the heat got to it.

I’ve sent an email to jungle and hopefully they’ll send me that axle and bolt once they agree on torque setting being ridiculous. Now need to send my wiggle pro torque wrench back for refund and and pick up one that’ll last longer!!

Maybe a crap idea, but I had success getting a bolt out in a similar situation by punching a mark on bolt, drilling a wee hole carefully with handheld drill, taping a small torx bit into the hole reasonably gently with hammer so it bit into the bolt then turning the bit. Was enough torque to turn the bolt given that it wasn’t under tension after the head broke off. A bit of a bodge but remarkably effective.

Torque spec on the Bronson V1 was revised to 80/50 inch-pounds (9/5.5Nm) for the big/small linkage bolts around 2015.

I removed a few ruste crumbly headed bolts yesterday. Beware the smallest screwfix extractor because it’s too small to get any purchase. The second is fine and probably what you need for most bike jobs. I also used a Grab-It that works if the metal is soft – rounded hex bolts for example.

For an expensive frame, I’d pay someone else to do it.

Ah yes, the Santa Cruz torque specs. I did the same and snapped mine on my old Nomad using a torque wrench to the exact spec. Contacted Jungle about it and they laughed at the torque specs, said they’re probably a bit high, and sent me some free bolts.

Yeah, I was warned not to pay too much attention to torques, especially for the axle bolts (rather than the tapered ones) which need to be set by feel, a little like a headset would be done.

On mine, the specified torques feel about “right”, however, so I’ve just stuck with ’em. Glad Jungle treated you right anyway.

Now need to send my wiggle pro torque wrench back for refund and and pick up one that’ll last longer!!

Depending on the bolt size and spec, it might be working as it should. An M5 bolt might only take 90 in lbs before snapping