Aluminium seat post identification, for removal/replacement purposes.
#26
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What is it that you have already done, that didn't work ? I don't get it.
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...just a couple of random thoughts. they may or may not help you.
1. the best penetrant, by far, is a 50/50 mix of acetone and automatic transmission fluid.
2. I have owned a couple of posts that were designed like that, and they did not work well. You can help them work better, by increasing the friction of the large flat surface on that curved top, but they tend to slip unless the bolt is tightened excessively. I just replaced mine with a different design.
3. when you struggle with trying to get it to break free, it helps a lot to install an old, junk steel saddle frame, or a crummy saddle you can sacrifice, into the post, Then you can pound and twist on the saddle frame, not the post clamp. If youi have access to a solid mounted bench vise, you can clamp the steel saddle frame in the vise, and twist the bike frame itself, to break it free of the post.
...just a couple of random thoughts. they may or may not help you.
1. the best penetrant, by far, is a 50/50 mix of acetone and automatic transmission fluid.
2. I have owned a couple of posts that were designed like that, and they did not work well. You can help them work better, by increasing the friction of the large flat surface on that curved top, but they tend to slip unless the bolt is tightened excessively. I just replaced mine with a different design.
3. when you struggle with trying to get it to break free, it helps a lot to install an old, junk steel saddle frame, or a crummy saddle you can sacrifice, into the post, Then you can pound and twist on the saddle frame, not the post clamp. If youi have access to a solid mounted bench vise, you can clamp the steel saddle frame in the vise, and twist the bike frame itself, to break it free of the post.
A sacrificial saddle is unlikely to provide enough grip or leverage. I'd put that post in a bench vise, protected by wooden blocks, of course. Spray the inside with penetrant, let it soak for a few days, and then start with short, sharp twisting efforts on the frame. Resist the urge to use a hammer or cheater bar.
....this may be your opinion, but I can assure you that I've done this plenty of times, and in fact, keep an old leather saddle frame (minus the leather) hanging over on one corner of the tools pegboard for exactly this purpose. It works quite well, and you don't need any wooden blocks or other protections for the saddle frame, because it is not necessary to protect it. Why in the world would you think that grabbing a sacrificial saddle frame, attached to the post via the post's own clamp, and fixed on a bench vise, would have less "leverage" in using this method to twist the frame off the post ? It's the same operation. But by avoiding any clamping force directed from the vise to the post, it protects the post and clamp itself.
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Yes, if you're talking about your last quote. Look, I didn't say don't use the penetrant of your choice, I said use a penetrant. I didn't say don't use a sacrificial saddle, I said, if that fails use a bench vise. You said the bench vise won't work. I said, I already used a bench vise after trying everything else, and it did work. For the record, I wrecked a saddle before I tried the bench vise.
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Yes, if you're talking about your last quote. Look, I didn't say don't use the penetrant of your choice, I said use a penetrant. I didn't say don't use a sacrificial saddle, I said, if that fails use a bench vise. You said the bench vise won't work. I said, I already used a bench vise after trying everything else, and it did work. For the record, I wrecked a saddle before I tried the bench vise.
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OK, I see the problem, the sacrificial saddle to be used for pounding on, thus saving the seat post or frame from damage. I shouldn't have put it that way. Yes, if you have to pound, doing it to an old saddle is a good idea. Sorry to have dismissed your idea like that. It was meant to be helpful. When I sacrificed my saddle, I was only using leverage. Come to think of it, I may had the saddle in the bench vise at one point.
Last edited by oldbobcat; 10-02-22 at 07:16 PM.
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