Worn seat-post clamp-bolt-thingy, help!

DonDaddyD

The allen key thread on the bolt that goes though the seat post clamp has worn away.

How do I go about removing the seat post clamp?

Ive bought a hacksaw to saw away the exposed bit of the bolt, but isn't there an easier way?

davis

Do you mean the thread??

Or (more likely) do you mean the head? I.e. the hexagonal cut-out, in which case the usual answer is to get a torx head screwdriver (preferably not a cheap one, 'cos you'll probably chew it up), cover it in screw grab, and undo it.

Edit: the torx bit tends to have to be a bit bigger than the hex bolt, so the splines catch in the corners.

tailwindhome

DonDaddyD wrote:

The allen key thread on the bolt that goes though the seat post clamp has worn away.

How do I go about removing the seat post clamp?WITHOUT DAMAGING THE CARBON SEAT POST

Ive bought a hacksaw to saw away the exposed bit of the bolt, but isn't there an easier way?

FTFY

rjsterry

Put the hacksaw down.

Step away from the hacksaw.

Now, is it the threaded end that's worn, or the head of the bolt?

If you've stripped the inside of the head (so the allen key turns without moving the bolt) then try davis's suggestion. Seat clamps normally take a 4mm allen key I believe. If it's the threaded end, then just carefully unscrew the bolt as normal.

If it doesn't look as though you can get it out without damaging the clamp, frame or seatpost, then get a shop to do it.

mudcow007

if the head isnt allen key shaped any more an you cut across the head the the hack saw an get a big flat head screw driver into the slot you just cut?

or if all else fails epoxy resin stick an allen key to the bolt, leave it a day or so to harden then try an remove it,

Kieran_Burns

mudcow007 wrote:

if the head isnt allen key shaped any more an you cut across the head the the hack saw an get a big flat head screw driver into the slot you just cut?

or if all else fails epoxy resin stick an allen key to the bolt, leave it a day or so to harden then try an remove it,

the flat head or a philips gently knocked into the end has done it for me (they'er cheaper than torx)

jeremyrundle

Lay the bike flat on a workmate and use a steel drill. 5 minutes to remove the head and knock out the bolt.

notsoblue

jeremyrundle wrote:

Lay the bike flat on a work mate and use a steel drill. 5 minutes to remove the head and knock out the bolt.

Paging HR to thread...

DonDaddyD

davis wrote:

Do you mean the thread??

Or (more likely) do you mean the head? I.e. the hexagonal cut-out, in which case the usual answer is to get a torx head screwdriver (preferably not a cheap one, 'cos you'll probably chew it up), cover it in screw grab, and undo it.

Edit: the torx bit tends to have to be a bit bigger than the hex bolt, so the splines catch in the corners.

Thanks, I mean:

Or (more likely) do you mean the head? I.e. the hexagonal cut-out

Any links to this screwdriver you mentioned would be greatly appreciated.

davis

Oh, I'd assumed you'd have one... :-)

Although, seriously, if you don't use them that often then a set of interchangeable bits would probably do. You'll be wanting something in the T20 - T25 range, from memory.

If you do need them regularly, then a decent set is worthwhile - here's the set I use:

http://www.rapidonline.com/Tools-Fasteners-Production-Equipment/Hand-Tools/Screwdrivers/Torx-screwdrivers/34672/kw/torx

Course you'll now get a billion comments of "nah, that make's crap, you want OTHERMAKE"

Screw Grab is worth its weight in gold.

Other options are: cutting a slot in the head with a hacksaw (don't, you'll fluff it up), drilling it out (much fluffing it up), using screw extractors (possibly slightly less fluffing, assuming you've got a steady hand)

[edit]: I'd have thought one of the "bit kit" sets like this: http://www.rapidonline.com/Tools-Fasteners-Production-Equipment/Hand-Tools/Screwdrivers/33-piece-bit-set/180831 would do for you. Course, being an Alpha Male you'll already have one

rjsterry

The point to point diameter of a 4mm allen key is 4.62mm, so a T25 Torx (at 4.43mm point to point) should fit, or you might need to jump up to T27 if you've really ground it out.

The Rookie

Personally I'd hacksaw a slot and use a screwdriver, but if D (having lost 2 D's again) hasn't got one and as we know he struggles with most menial mechanical tasks I'd suggest he uses an LBS!

Simon

DonDaddyD

If you hacksaw the bolt the bit that is visible (facing the rear wheel) between the clamp what do you do with the screwdriver.

I'm assuming pry open the clamp itself....

That solution sounds the most fun...

nicklouse

DonDaddyD wrote:

The allen key thread on the bolt that goes though the seat post clamp has worn away.

How do I go about removing the seat post clamp?

Ive bought a hacksaw to saw away the exposed bit of the bolt, but isn't there an easier way?

So you are not talking bike here at all.

Pics so can see what the actual issue is,

is it a separate clamp? or built in or........

DonDaddyD

The bike is Giant SCR3.

The seat post clamp is separate from the frame.



The bit of the bolt that I'm thinking of taking the hacksaw to is visible in the image above.

The the head of the bolt I.e. the hexagonal cut-out (where the allen key would go to tighten or loosen it) has been rounded off so that the allen key doesn't tighten or loosen - it sort of skips rounding it off further.

rjsterry

NO!

Unless of course you don't mind binning the clamp - you'll really struggle to get two bits of bolt out. If you don't mind, buy a replacement before you do it. There's a;so a risk of you slipping and gouging the seat post.

As I said, ditch the hacksaw, get a suitably sized flat screwdriver (that fits tightly into the head of the bolt), tap it in gently with a hammer, and then very gently twist - you are trying to use just enough torque to get the bolt out and no more, to avoid stripping the head even more.

kelsen

Yeah, I say you probably need something like this...

jejv

I think I'd try assorted interchangeable screwdriver bits - like torx, and failing that drill the bolt with a Dremel and use a bolt extractor.

Does anyone else have popcorn ready yet ?

Take it to the LBS. Okay?

nicklouse

DonDaddyD wrote:

The bike is Giant SCR3.

The seat post clamp is separate from the frame.



The bit of the bolt that I'm thinking of taking the hacksaw to is visible in the image above.

The the head of the bolt I.e. the hexagonal cut-out (where the allen key would go to tighten or loosen it) has been rounded off so that the allen key doesn't tighten or loosen - it sort of skips rounding it off further.

TBH a dremmel type thing would be better as you will have very limited access with a hack saw.

But my option woild be to drill the head off the bolt. and fit a new clamp.

EKE_38BPM

The Beginner wrote:

Personally I'd hacksaw a slot and use a screwdriver, but if D (having lost 2 D's again) hasn't got one and as we know he struggles with most menial mechanical tasks I'd suggest he uses an LBS!

Simon

Now, now. Play nice.

Some people are less mechanically minded than others and make up for it in other ways, such as being good at relationships, art apreciation and dealing with other people and their feelings.










These people are usually called women.

redvee

Carefully hacksaw along the marked red lines.

http://imageshack.us/photo/my-images/685/image1vbv.jpg/

shouldbeinbed

DonDaddyD wrote:

If you hacksaw the bolt the bit that is visible (facing the rear wheel) between the clamp what do you do with the screwdriver.

I'm assuming pry open the clamp itself....

That solution sounds the most fun...

No not like that. On the top of the bolt where the allen key goes into, cut a slot across the top and then treat it like a flat head screw.

Warning tho, this'll only work if enough of the head is exposed from the clamp. If not then go and ask your LBS,

If you cut through the bolt anywhere, you've still got the bolt bits to get out

jejv

We're in suspense.

D - have you killed your bike yet ?

If so, we might be interested in the wheels, the brakes and the seat. PM me if you are still alive.

SteppenHerring

Is there enough space in the gap in the clamp to get an angle grinder disc in? Because that's loads easier than a hacksaw. Alternatively you might want to see of you can get enough grip on the head with a mole wrench to turn it. Ease it up a bit first by heating gently with an oxyacetylene torch.

Or, as someone said, see of you can TAP GENTLY a torx key or a flat blade screwdriver into the head enough to get some purchase. If you can lay the bike flat and put a brick or something under the other side of the seatpost clamp so your gentle tapping is going through the metal clamp rather than the carbon frame, that might be a thing as well. Or get a mouse to gnaw through the seatpost.

itboffin

Explosives that's the way forward.

graham.

If you take the hacksaw/cutting route. Don't use a hacksaw. Beg, steal or borrow one of those Dremmel jobies and a few cutting discs. Much neater and more controllable. (As long as you don't slip!)
Graham.

EKE_38BPM

itboffin wrote:

Explosives that's the way forward.

Thats your answer to everything!

CiB

itboffin wrote:

Explosives that's the way forward.

<pictures scene DDD with hands on hips>

You're only sapposed to blow the bladdy seatpost off.

jejv

SteppenHerring wrote:

Is there enough space in the gap in the clamp to get an angle grinder disc in?

Oi. You're just after bits of his bike. I was there first.

While we're waiting for news, it occured to me that a bolt extractor might fit in what's left of the hex socket on the end of the bolt, without any drilling. Would that work ?

rjsterry

itboffin wrote:

Explosives that's the way forward.

"When I was in the army..."

mudcow007

if the bolt is truly goosed, you will probably be needing a whole new clamp anyways, so why not gently cut across the clamp its self, it will only be alloy so way easier to cut that then bolt.

when you are through the clamp stick a flat bladed screwdriver in the cut you just made an pries the whole thing off

simples