look up seatpost extractor tool and see if it’s of any help.
If it was me, I would drill a hole in it, then stick a screwdriver through the hole. Then try to break it free by tapping on it with a hammer. If it loosens, you will then be able to unscrew it like a corkscrew by the screwdriver 🪛
wookieewrenches on
Send as much penetrating oil down there as you can, let it sit for a day. If you have access to a pipe vise, clamp the end of the post in the pipe jaws and use the frame as your lever
tiregroove on
I cannot believe we are still discussing the most over-the-top brute-force solutions for this.
JUST BUY A 1″ (25.4mm) DRILLBIT and DRILL IT OUT.
Cut what’s left of the post a 1/4 inch from the top first. It takes 3 minutes, and what’s left is a paper-thin shard of aluminum that pulls right out. NO caustic chemicals necessary. You should have cutting oil for the drillbit though.
Willing-Bowl-675 on
Just to be sure:
Does “everything” include just mounting a big saddle and use it as grip to get it out with rotation?
You can try drilling a hole through the top, put something like a metal tire lifter in there, put the seatpost in a vice and then use the frame as lever to get the post rotating. (The hole with the tool inside gives a lever for the rotation if the vice has not enough grip.)
Once it rotates you can get it out with back and forth rotating movement while pulling.
MaksDampf on
Just dissolve it.
Its Aluminium, so any pipe cleaning agent, granulate or solution that includes NaOH will dissolve it without harming the steel or paint. You can get it in any drug store for around 2$.
I would probably seal the BB at the bottom and bosses and then fill it up with water and NaOH granulate. But you can also submerge it upside down in a bassin. Heating the water will speed up the process. Use gloves, keep the area ventilated and don’t inhale the fumes!
Make sure it is not oily, use isopopanol or acetone to remove it, since that would shield the aluminium from being penetrated. scrubbing the anodizing off with a file inside also improves the decomposition speed.
Wooden-Combination53 on
Anyone tried dry ice? Aluminium will shrink more than metal and maybe would loosen things
fringe1992 on
There is an old method that consists of filling the rest of the visible seatpost near the beginning of the seat tube
Then you file the visible seat post on the back opening of the seat tube
This will basically turn the current post into a “shin”
Then you find the inner diameter of the post and get a new seatpost that will fit in there
Reynolds531IPA on
Not budging whatsoever? Sounds like it’s galvanically corroded. Caustic solution is the only way.
ENTroPicGirl on
You want to use gallium. Cut the seat post flush take a high-speed drill with a wire brush on it. Hit the inside of that dig yourself a little trench with a file and use a syringe filled with gallium and put some of that into the trench. You will need to keep it level for a day or so but the Gallium will eat the aluminium away so you can extract.
The advantage of the gallium method is that you can pull this thing out of the steel frame. It won’t damage any paint and you don’t have to deal with caustic chemicals that can actually burn your skin and also damage your floor covering and everything else that comes in contact with.
Kanaimma on
Weld it perpendicularly to a thick bar to serve as a rotating lever. You are turning it like a screw The bigger and stronger the one above, the easier it will be for you.
1. Drill hole. 2. Get 5kg slide hammer from auto parts shop. 3. Attach slide hammer to bolt placed in hole. 4. Go to fucking town.
I’ve only had one stuck seatpost not be able to be removed via this method (bolts kept breaking or straight up ripping the alu apart) and it was a pretty special case… where it was just completely fucked already by someone else.
JoeTouchdown on
Penetrating oil in the bottom bracket hole, uppend the whole frame. Then hammer that seat post flat ish and get it in a vice. Then use the whole frame as a lever to brake it free
12 Comments
look up seatpost extractor tool and see if it’s of any help.
If it was me, I would drill a hole in it, then stick a screwdriver through the hole. Then try to break it free by tapping on it with a hammer. If it loosens, you will then be able to unscrew it like a corkscrew by the screwdriver 🪛
Send as much penetrating oil down there as you can, let it sit for a day. If you have access to a pipe vise, clamp the end of the post in the pipe jaws and use the frame as your lever
I cannot believe we are still discussing the most over-the-top brute-force solutions for this.
JUST BUY A 1″ (25.4mm) DRILLBIT and DRILL IT OUT.
Cut what’s left of the post a 1/4 inch from the top first. It takes 3 minutes, and what’s left is a paper-thin shard of aluminum that pulls right out. NO caustic chemicals necessary. You should have cutting oil for the drillbit though.
Just to be sure:
Does “everything” include just mounting a big saddle and use it as grip to get it out with rotation?
You can try drilling a hole through the top, put something like a metal tire lifter in there, put the seatpost in a vice and then use the frame as lever to get the post rotating. (The hole with the tool inside gives a lever for the rotation if the vice has not enough grip.)
Once it rotates you can get it out with back and forth rotating movement while pulling.
Just dissolve it.
Its Aluminium, so any pipe cleaning agent, granulate or solution that includes NaOH will dissolve it without harming the steel or paint. You can get it in any drug store for around 2$.
I would probably seal the BB at the bottom and bosses and then fill it up with water and NaOH granulate. But you can also submerge it upside down in a bassin. Heating the water will speed up the process. Use gloves, keep the area ventilated and don’t inhale the fumes!
Make sure it is not oily, use isopopanol or acetone to remove it, since that would shield the aluminium from being penetrated. scrubbing the anodizing off with a file inside also improves the decomposition speed.
Anyone tried dry ice? Aluminium will shrink more than metal and maybe would loosen things
There is an old method that consists of filling the rest of the visible seatpost near the beginning of the seat tube
Then you file the visible seat post on the back opening of the seat tube
This will basically turn the current post into a “shin”
Then you find the inner diameter of the post and get a new seatpost that will fit in there
Not budging whatsoever? Sounds like it’s galvanically corroded. Caustic solution is the only way.
You want to use gallium. Cut the seat post flush take a high-speed drill with a wire brush on it. Hit the inside of that dig yourself a little trench with a file and use a syringe filled with gallium and put some of that into the trench. You will need to keep it level for a day or so but the Gallium will eat the aluminium away so you can extract.
The advantage of the gallium method is that you can pull this thing out of the steel frame. It won’t damage any paint and you don’t have to deal with caustic chemicals that can actually burn your skin and also damage your floor covering and everything else that comes in contact with.
Weld it perpendicularly to a thick bar to serve as a rotating lever. You are turning it like a screw The bigger and stronger the one above, the easier it will be for you.
https://preview.redd.it/ywsm4byrf4of1.jpeg?width=1024&format=pjpg&auto=webp&s=dc3fc7d1aa7aaf76d34d1aec648772155a44e75a
1. Drill hole. 2. Get 5kg slide hammer from auto parts shop. 3. Attach slide hammer to bolt placed in hole. 4. Go to fucking town.
I’ve only had one stuck seatpost not be able to be removed via this method (bolts kept breaking or straight up ripping the alu apart) and it was a pretty special case… where it was just completely fucked already by someone else.
Penetrating oil in the bottom bracket hole, uppend the whole frame. Then hammer that seat post flat ish and get it in a vice. Then use the whole frame as a lever to brake it free