broken seat post loose in seat tube
 

OK kids, Advice?
My FSA carbon post cracked off at the clamp. The post was corroaded in hte steel Fierte seat tube. I sawed grooves, pried and peeled out 3 or 4 inches of post. The last inch or two of the carbon post fell down, loose to the bottom bracket becasue the seat tube is double butted at the top by the clamp. It rattles when I ride.
The remaining seat post is frayed out like Bart Simpsons head so it won't come out. I can just grab it with my needle nose pliers or hook it with a coat hanger but can't pull it out.

Do I epoxy it in, down out of the way?
Do you invent a nibbler for me to chew out the remaining piece?

The epoxy will add weight!

what about taking it out the bottom?
take out you're BB, use something to push the post through into the bb shell, and then bust it up with a screwdriver or something

might work, or might be way too much hassle.

epoxy sounds messy but a lot easier.
make sure you don't let any drip onto your bb - those things are hard enough to get out when they're not glued in place.

Good thoughts. The bottom bracket was removed during the first operation. Alas, Serotta seat tube to bottom bracket is only a 3/8" hole so no chance for a southernly exit. I need a narrow, wicked long nibbler.

can you get a long stick with a dob of good epoxy glue on the end and a flash light. carefully Glue the sick to the fragment wait and pull.

Look here: http://www.bikeforums.net/showthread.php?t=428324

Instant replay?

Forceps, a hacksaw blade, and a lot of time.

Squirt some insulation foam in through the hole through the BB. That will keep it from rattling around.

And cause the frame to rust out, both by blocking drainage, and because insulation foam is open-cell, and will hold water.

Good thoughts. Thanks. I will not go foam or epoxy (yet) and try forceps and hack saw it is. As Hill mentioned I'm still angsting and tried this new thread after looking for help in a related thread. I should have linked. I'll report back.

A CF/steel rattle is probably not as annoying as an aluminum/steel rattle.

If concerned about water passing through to the BB all he would need to do is make a small hole to allow water to pass on through.
Best idea is to send it back to Serotta and have them get the messed up post out. May involve cutting and rewelding and paint but probably better than any advice that can be found on a bike forum.

This is going to be odd, but it may be worth a shot. I am assuming this is probably a 27.2 Seatpost and if it is, it will probably be too small, but if you could get an old 1" quill stem to engage the post it would give you some grip and you could try to pull it despite the fraying. I am trying to think if there is another part with a smaller diameter that would fit inside the seatpost and do the same thing. You may also want to try a segment of chain with a nail in one end. drop the nail through the post straight and then get it to "T" so that it will engage the backside of the post. (did that make sense?) Then use the chain to pull the broken post up and out.

ok lets make a tool. buy a 3' long threaded 1/4 rod at home depot, and a rubbber bottle stopper from some science supply place. with nuts and washers on both sides of the stopper, which has a 1/4 drilled in the middle, and it just fits inside the broken off seatpost. now you insert the stopper into the seatpost and will need to tighten the nuts, which will make the stopper grab the inside of the seatpost. we will need a tool to tighten the nut....I'm thinking a 7/16 socket epoxyed into a
1/2 emt that is longer than your seatube, but is shorter than the threaded 1/4 rod.....just a quick idea. practice on the top piece of the seatpost to see if the rubber stopper is the right size, uncompressed it need to just fit the inner diameter of the post

WoW! Creative! This is worth a shot. Stay tuned.

home made tool?
 

Here is my first illustration showing the issue.
The second drawing is a dead end idea of screwing down a home made cutter. The bottom cone will splay out and center the insert tube so it won't pull through. It needs to go back to a small diameter to pull it back out. I'm as fuzzy as the carbon tube how that wil work.
The idea is the cutter washer will scribe the inside diameter of the carbon post remnant. The cutter has to fit inside the seat post and be centered past the Bart Simpson head of frayed carbon.

Just to finish off our story, probably in error I started this thread then told the same story in another thread. I just wanted to let you know, after riding too long with a rattling seat post remnant I finally cut out the culprit. All's well and thanks for your support.

The lessons learned:
http://www.bikeforums.net/showthread...=428324&page=2

"the seat tube is double butted at the top by the clamp"

Only if the seat tube was installed upside down.

Glad it worked out for you. BTW park makes a tool for pulling out busted seatposts- more of a shop tool than diy, perhaps your shop has one.

Double butted seat tube at seat post end
 

Dirtdrop,
In this case, by double butted I mean a smaller inside diameter at the seat post end. Serotta does it in the Fierte with a drilled out sleeve about 2 or 3 inches long. It is a sharp edge, not tappered so the frayed carbon caught.

Turn bicycle upside-down. Shake. No go? Fashion a hook out of a coat-hanger. Deliver the carbon-baby.:D

Park seat post tool
 

Frankenmike,
Hmmm, Nope I don't know about this tool.
I though about making a tool to guide a scribe like a keyway cutter but once I got a sacrificial blade between the seat tube and the seat post remnant how could I not use a wobbly, loud, satisfying Sawzall?

Do you mean the internal seat tube clamp? Park discontinued a fancy version of a traditional wedge/quill stem for a threaded fork. http://www.parktool.com/products/doc...5812_86665.pdf
They replaced it with an internally expanding clamp http://www.parktool.com/products/doc...SC-4_Parts.pdf
In this case neither would have worked because of the splayed carbon fibers jamming under the sleeved seat tube top.

You can also use a heat gun and funnel the heat into the seat tube, wait for the epoxy to melt, push it through and scoop it out your BB. High heat + CF = gooey.

That's what I was going to suggest - carbon fiber epoxy burns, right? Then light the sucker on fire. Lighter fluid and a match should allow it to get hot enough to be pliable and allow you to pull at least part of it out. Or it'll melt to the inside of the seat tube, in which case you wouldn't need the epoxy you were initially going to try. Something like toluene might do the same job, depending on the carbon fiber resin. Both would be hell on your paint, most likely.

You could also try taking 2-3 feet of that 1/4" all thread rod with a drum sander bit bolted to the end and shove that down into the broken-out seat post from the top, putting it into a drill and going nuts with the whole thing until you reduce the post to dust from the inside out.

Or plug up the bottom end of the broken tube, fill the space between the end of the tube and the bottom bracket shell with butane gas, and light that on fire. Might build up enough speed to rocket out the top end of the seat post.

I'm not saying these is a good idea, but one might work.

You guys are the best of the bike forum with creative solutions to odd ball problems. I hope these get archived somewhere. They really are helpful when cranking through unusual problems.

I worried about heat damaging paint and maybe the glued carbon backstay. Same thing with powerful solvents.

The Serotta Fierte configuration with the sleeved top of the seat tube caused the problem and enabled the solution. It allowed space to shove a sacrificial saw blade under the seat post remnant and Sawzall to death the remnant. Sawing by hand would have taken 15.7 hours* because the remnant was so deep in the seat tube it was difficult to get pressure on a saw blade.


*calculated from progress after 45 minutes.