Seat pin stuck in an ALAN frame... suggestions?

[whistlestop]

I have an ALAN (aluminum of course) frame with a Campy (aluminum of course) seat pin stuck in it, none of the normal Tricks have proven successful. So far, I have spread the seat lug (stuck a nickel in the slot to keep it open), removed the BB and filled it with all manner of penetrating lubes and concoctions and let it sit for awhile (a year), yelling and screaming and cursing, tapping (carefully) down (did not move), inverted and held the post in a vise and tried twisting (did not move).

I am PRETTY sure that it is the original seat pin so have ruled out someone jamming a too-large pin into the frame.

Does anyone have other ideas to remove an aluminum seat pin from an aluminum frame??

 

[RustySprockets]

One of my cohorts once freed a stuck post by heating the outer tube, then plunging the exposed part of the seat post into a bucket of ice-filled water. It's a pretty aggressive solution, but the temperature differential might just break the choke hold. It worked for him.

 

[whistlestop]

Thanks for the suggestion. My concern about heating the seat tube since ALAN frames are bonded, not welded. Glue doesn't like heat. On top of that is the concern in annealing the tube.

 

[coasterbrakejunkie1969]

I have an ALAN (aluminum of course) frame with a Campy (aluminum of course) seat pin stuck in it, none of the normal Tricks have proven successful. So far, I have spread the seat lug (stuck a nickel in the slot to keep it open), removed the BB and filled it with all manner of penetrating lubes and concoctions and let it sit for awhile (a year), yelling and screaming and cursing, tapping (carefully) down (did not move), inverted and held the post in a vise and tried twisting (did not move).

I am PRETTY sure that it is the original seat pin so have ruled out someone jamming a too-large pin into the frame.

Does anyone have other ideas to remove an aluminum seat pin from an aluminum frame??

Are you talking about the seat post?

 

[coasterbrakejunkie1969]

It is my understanding that the aluminium can react with other materials and become fused together. Not sure there is anything that can be done at that point other then having a machine shop drill it out.

 

[RustySprockets]

Thanks for the suggestion. My concern about heating the seat tube since ALAN frames are bonded, not welded. Glue doesn't like heat. On top of that is the concern in annealing the tube.

AH! I follow--they're a bonded frame, like the Technium. In that case, I'd avoid heat, too. Any chance you can post a photo of what you're dealing with? It sounds like you've already spent a lot of time and effort applying the usual tricks.

 

[HEMI426]

If all else fails and originality is not that important and rideability is. A crude fix would be to cut off the seat post flush at the top of the tube, take a dye grinder and cut a slice in the tube and stem so a pinch seat clamp would tighten. Put a smaller diameter seat post in, tighten it up , put on your seat and ride, ride, ride.

 

[coasterbrakejunkie1969]

Still insure what a seat pin is

 

[nauseated]

Since you can easily replace the seat post, it may have to be sacrificed. Remove the extra parts from the post and while upside down put the top of the post in a vice, then turn the frame.

 

[Schwinn Sales West]

Since you can easily replace the seat post, it may have to be sacrificed. Remove the extra parts from the post and while upside down put the top of the post in a vice, then turn the frame.

Ouch, guys it's a CAMPY seat post in a high dollar frame.

Let's try some more less destructive measures before we go gonzo.

How about using some vibration to work the oil into the corroded area. With the bike upside down, place the seat post into a vise with the seat clamp parts removed, and the post head protected by some wood in the vise. Remove the crank spindle and pour some oil into seat tube. If the oil does not run out, fill up the entire Campy seat post hollow section so you make sure you have enough to reach the frame/seat post junction. Without discussing the entire penetrating oil topic again, just thin the oil of your choice with some Acetone to make the oil very thin and penetrate the tight area between the post and the frame. Take a Plastic or Rubber Hammer and tap the frame around the seat tube/seat post area. You could even take an air hammer, turn the air pressure down, and use a block of wood to protect the seat tube. Vibrate the frame seat post through the block of wood.

The key is to work slowly, have patience. Work the stuck item "back and forth", do not force it, you will feel when it starts to move. This is some of the ways I have removed stuck seat posts, and stuck stems/wedges in steerer tubes. It will come out. It could take several days for the oil to soak with the frame upside down.

When you get it out, you will need to run a hone down the frame seat tube to clean out the corrosion. You need to mic the seat post and inside the frame seat tube to make certain the seat post size is correct. A very light coat, VERY LIGHT coat of anti-seize will prevent the two parts from sticking in the future.

Good luck with your project

John