How would you get this seatpost removed?
#1
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How would you get this seatpost removed?
There is a sad Paramount frame on eBay now. I am not interested in buying, have too many projects already, but it has me wondering how to properly remove a stuck seatpost.
It looks like someone has used a pipe wrench and grinder on this unfortunate victim, but it seems a shame to toss it in the dumpster.
How would you go about getting this one freed up? Is it too far gone?
It looks like someone has used a pipe wrench and grinder on this unfortunate victim, but it seems a shame to toss it in the dumpster.
How would you go about getting this one freed up? Is it too far gone?
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Upside down over a plastic bucket,
NaOH solution poured down the inside of the seat-tube - don't make it to strong, wear protective gear - and wait a week (you can take the gear off).
NaOH solution poured down the inside of the seat-tube - don't make it to strong, wear protective gear - and wait a week (you can take the gear off).
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I would turn it upside down and fill the seat tube with a 50/50 mix of acetone and ATF. Wait a week and then remove the post from the frame. Cutting it out would be a last resort. I have step drills to ream out the aluminum as well which involves a bit more time but would not damage the frame. I would use lye as a last possible resort, It is messy and requires a lot of patience. Smiles, MH
#5
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In the last stuck seatpost thread, someone recommended taking the frame to an auto shop and having them use an air hammer on the underside of the seat clamp to remove a stuck seatpost. I don't have personal experience with this method, but this frame looks like a good candidate.
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...it looks like an older Campy style seatpost. So there's probably not that much of it inserted (compared to the longer seatposts you sometimes encounter. That's a plus.
Whoever took a grinder to it, didn't do anyone a favor, because you can't still clamp a saddle frame in there for more leverage. That's a minus.
The paint is kinda shot, so you can use heat with abandon. That's a real advantage. I'd use a combination of the ATF/acetone mix, applied from the top and in the slot, and from the bottom, as mentioned already. Then some heating and cooling cycles with a Mapp gas or propane torch, and maybe some cooling shock to the post with Freeze Off. Then more ATF/acetone right before you try to twist it out. Then clamp what remains of the top in a solidly mounted bench vise, and twist off the frame. Try to get the seatpost clamp loose at the top by prying the ears open a little. If it's really stuck there, there is some risk of tearing the seat tube in the location of the slot. That makes the frame useless.
None of this stuff is 100% guaranteed, but it works most of the time without damaging the frame.
...it looks like an older Campy style seatpost. So there's probably not that much of it inserted (compared to the longer seatposts you sometimes encounter. That's a plus.
Whoever took a grinder to it, didn't do anyone a favor, because you can't still clamp a saddle frame in there for more leverage. That's a minus.
The paint is kinda shot, so you can use heat with abandon. That's a real advantage. I'd use a combination of the ATF/acetone mix, applied from the top and in the slot, and from the bottom, as mentioned already. Then some heating and cooling cycles with a Mapp gas or propane torch, and maybe some cooling shock to the post with Freeze Off. Then more ATF/acetone right before you try to twist it out. Then clamp what remains of the top in a solidly mounted bench vise, and twist off the frame. Try to get the seatpost clamp loose at the top by prying the ears open a little. If it's really stuck there, there is some risk of tearing the seat tube in the location of the slot. That makes the frame useless.
None of this stuff is 100% guaranteed, but it works most of the time without damaging the frame.
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Well I'm normally the last one to disparage a Paramount but this guy is on the moon IMO.
It might be worth $279 + ship IF the SP was out and there are absolutely NO other problems or surprises like no returns.
He also has most of the grimey, grungy parts from it listed for equally over optimistic prices as well.
It might be worth $279 + ship IF the SP was out and there are absolutely NO other problems or surprises like no returns.
He also has most of the grimey, grungy parts from it listed for equally over optimistic prices as well.
Last edited by merziac; 03-20-23 at 10:42 AM.
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I agree, $279 is too much.
He stripped EVERYTHING off of the frame but not the seatpost, that speaks for itself. Too risky or at the least, too much work.
He stripped EVERYTHING off of the frame but not the seatpost, that speaks for itself. Too risky or at the least, too much work.
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Only because I had a whiskey bar at the time, and we were getting deliveries of dry ice, I dropped some dry ice pellets from the BB, small enough to go into the seat post. The aluminum contracted enough to come loose.
PS, this was also after a week's worth of daily PB Blaster spraying.
Good luck.
PS, this was also after a week's worth of daily PB Blaster spraying.
Good luck.
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...I wonder why anyone would think that was worth $280 ?
...I wonder why anyone would think that was worth $280 ?
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I used drain cleaner to remove this rather massive bar stem:
Outside, of course. Keep water within reach:
After a few hours:
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#12
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Given the price of Paramount framesets in general, the ask wasn't horrible. And it's gone BTW.
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...it looks like an older Campy style seatpost. So there's probably not that much of it inserted (compared to the longer seatposts you sometimes encounter. That's a plus.
Whoever took a grinder to it, didn't do anyone a favor, because you can't still clamp a saddle frame in there for more leverage. That's a minus.
The paint is kinda shot, so you can use heat with abandon. That's a real advantage. I'd use a combination of the ATF/acetone mix, applied from the top and in the slot, and from the bottom, as mentioned already. Then some heating and cooling cycles with a Mapp gas or propane torch, and maybe some cooling shock to the post with Freeze Off. Then more ATF/acetone right before you try to twist it out. Then clamp what remains of the top in a solidly mounted bench vise, and twist off the frame. Try to get the seatpost clamp loose at the top by prying the ears open a little. If it's really stuck there, there is some risk of tearing the seat tube in the location of the slot. That makes the frame useless.
None of this stuff is 100% guaranteed, but it works most of the time without damaging the frame.
...it looks like an older Campy style seatpost. So there's probably not that much of it inserted (compared to the longer seatposts you sometimes encounter. That's a plus.
Whoever took a grinder to it, didn't do anyone a favor, because you can't still clamp a saddle frame in there for more leverage. That's a minus.
The paint is kinda shot, so you can use heat with abandon. That's a real advantage. I'd use a combination of the ATF/acetone mix, applied from the top and in the slot, and from the bottom, as mentioned already. Then some heating and cooling cycles with a Mapp gas or propane torch, and maybe some cooling shock to the post with Freeze Off. Then more ATF/acetone right before you try to twist it out. Then clamp what remains of the top in a solidly mounted bench vise, and twist off the frame. Try to get the seatpost clamp loose at the top by prying the ears open a little. If it's really stuck there, there is some risk of tearing the seat tube in the location of the slot. That makes the frame useless.
None of this stuff is 100% guaranteed, but it works most of the time without damaging the frame.
i would assume it is a longer one. The post, with some machine work and an aluminum rod could be saved.
inverted with a favored elixir might be the way to go with possibly some freeze off to help break the galvanic bond.
I use Kroil but acetone and ATF has a following.
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...so it was worth $280 on ebay ? I have a couple of good condition Paramounts I need to sell. I guess that's the place. Local prices were pretty sad last year.
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If the paint is a goner, then by far the fastest solution is melting the post out. I have a big rosebud tip for my oxy/propane torch, might melt out the stub (after hacksawing near the lug) in about a minute, 2 minutes tops. A propane weed-burner is a lot less expensive than my rig though, and should have no trouble melting alu. The one I linked to is a good one, $43, but you can get them for half that much, just lower output and shorter hose.
Don't breathe the burning-paint smoke though. I assume it's super toxic, though I don't have any proof of that.
Don't breathe the burning-paint smoke though. I assume it's super toxic, though I don't have any proof of that.
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does the heat affect the braze?
will there be aluminum residue in the frame's seat post?
will there be aluminum residue in the frame's seat post?
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Alu doesn't "wet out" or braze itself to steel. There will be some gunk, for example the product of the galvanic corrosion, but I think that's pretty much the same no matter how you get the post out. If you used, say, oil and brute force, there'd still be gunk in there that's worth getting out before putting a seatpost back in. But the molten alu just rolls out, in my experience.
I once did it over a crushed-rock ("gravel") driveway, and the molten alu penetrated a couple inches down between the rocks, gluing them together, so the whole lump came out like this:
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Aluminum melting point is too low to melt brass or silver, but it is possible to overheat the joint by inattention... so don't.
Alu doesn't "wet out" or braze itself to steel. There will be some gunk, for example the product of the galvanic corrosion, but I think that's pretty much the same no matter how you get the post out. If you used, say, oil and brute force, there'd still be gunk in there that's worth getting out before putting a seatpost back in. But the molten alu just rolls out, in my experience.
I once did it over a crushed-rock ("gravel") driveway, and the molten alu penetrated a couple inches down between the rocks, gluing them together, so the whole lump came out like this:
Alu doesn't "wet out" or braze itself to steel. There will be some gunk, for example the product of the galvanic corrosion, but I think that's pretty much the same no matter how you get the post out. If you used, say, oil and brute force, there'd still be gunk in there that's worth getting out before putting a seatpost back in. But the molten alu just rolls out, in my experience.
I once did it over a crushed-rock ("gravel") driveway, and the molten alu penetrated a couple inches down between the rocks, gluing them together, so the whole lump came out like this:
modern.
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https://orangecounty.craigslist.org/...601014465.html
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Put the item in a location that will be seen by the maximum amount of interested parties.
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Then I had a flashback to the 10 hours it took me to get a seat post out of a Specialized Expedition and passed.
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Folks, this is 2023, and stuck posts aren't the nightmare that they used to be.
Muriatic acid dissolves aluminum.
Alkali solutions embrittle steel.
Some of us have found that cutting off 1" above the opening and using a slender, sharp sawzall blade can get any stuck alloy post out fast, with no damage to the frame.
The tricks are:
1) Begin by probing with a bent spoke to determine the inserted length of the post.
2) Make certain (by means of probing with a sharpened bent spoke) that the slot in the post is cut through to the steel all the way to the bottom of the post.
3) Do not align/clock the cut with the slot in the lug.
4) Do not let the blade contact the edge at the lug opening, so keep the blade's cutting side tilted slightly at all times.
5) Make sure that the end of the blade can't/doesn't reciprocate/travel too high and thus "catch" above the upper end edge of the seat tube, remembering that the directional teeth will tend to try to push the saw and blade upward as the blade digs into the aluminum and reciprocates through it's perhaps 1" of stroke.
6) The cut height doesn't need to extend much above the height of bottom of the slot in the seat tube, and doesn't need to extend to the end of the seat tube.
Please read the above (5) instructions several times, slowly.
Be patient and controlled with the cutting, especially when starting out, and again when extending the cut to just barely above the height of the lower end of the slot in the frame's seat tube.
If the teeth out near the tip of the blade clog, or seem to become dull, they can be directionally sharpened using a Dremel "wafer" disc using good technique. The leading teeth should do all of the cutting. Cutting oil on the teeth recommended, any oil will do.
Once cut through to steel, the post can be easily twisted out. For heavier amounts of twisting force using plumbing pliers, put a reinforcing insert such as a dowel into the ID of the end of the post. Back-and-forth action and WD40 should make this easy.
I've had to "slenderize" a Sawzall blade on the bench grinder to cope with the narrow ID of the post.
I've had to sharpen the teeth at the tip of a used blade.
There is no tendency for the blade to dig into the steel, unless you let the teeth contact the edge at the opening or at the slot.
It takes a lot of concentrated pressure to get a Sawzall blade's teeth to even start digging into steel, which is pretty much impossible to achieve at the tip of the blade.
Muriatic acid dissolves aluminum.
Alkali solutions embrittle steel.
Some of us have found that cutting off 1" above the opening and using a slender, sharp sawzall blade can get any stuck alloy post out fast, with no damage to the frame.
The tricks are:
1) Begin by probing with a bent spoke to determine the inserted length of the post.
2) Make certain (by means of probing with a sharpened bent spoke) that the slot in the post is cut through to the steel all the way to the bottom of the post.
3) Do not align/clock the cut with the slot in the lug.
4) Do not let the blade contact the edge at the lug opening, so keep the blade's cutting side tilted slightly at all times.
5) Make sure that the end of the blade can't/doesn't reciprocate/travel too high and thus "catch" above the upper end edge of the seat tube, remembering that the directional teeth will tend to try to push the saw and blade upward as the blade digs into the aluminum and reciprocates through it's perhaps 1" of stroke.
6) The cut height doesn't need to extend much above the height of bottom of the slot in the seat tube, and doesn't need to extend to the end of the seat tube.
Please read the above (5) instructions several times, slowly.
Be patient and controlled with the cutting, especially when starting out, and again when extending the cut to just barely above the height of the lower end of the slot in the frame's seat tube.
If the teeth out near the tip of the blade clog, or seem to become dull, they can be directionally sharpened using a Dremel "wafer" disc using good technique. The leading teeth should do all of the cutting. Cutting oil on the teeth recommended, any oil will do.
Once cut through to steel, the post can be easily twisted out. For heavier amounts of twisting force using plumbing pliers, put a reinforcing insert such as a dowel into the ID of the end of the post. Back-and-forth action and WD40 should make this easy.
I've had to "slenderize" a Sawzall blade on the bench grinder to cope with the narrow ID of the post.
I've had to sharpen the teeth at the tip of a used blade.
There is no tendency for the blade to dig into the steel, unless you let the teeth contact the edge at the opening or at the slot.
It takes a lot of concentrated pressure to get a Sawzall blade's teeth to even start digging into steel, which is pretty much impossible to achieve at the tip of the blade.
Last edited by dddd; 03-22-23 at 11:17 AM.
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Well, I have to admit I thought about it for a minute. The 66cm Paramount's just don't come up very often and when they do the price is usually 3 or 4 times his asking price.
Then I had a flashback to the 10 hours it took me to get a seat post out of a Specialized Expedition and passed.
Then I had a flashback to the 10 hours it took me to get a seat post out of a Specialized Expedition and passed.
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Did you save that Weyless top and hardware? Could be used to make a new post by replacing the shaft part.
Or just the two plates and bolts at the top can be used on a "seat mast" where the seat tube extends all the way to the saddle rails. I did that in 1977 on a race bike I made for myself. I'll admit the seatmast idea is dumb, and I winced when that design made a comeback. (when was that, early 2000s?) But I was 19 years old when I made mine, young dumb and full of...
Those are Weyless parts just out of frame at the top. They're not super valuable, but they ain't makin' 'em anymore. The tall fulcrum the weyless clamps sit atop was due to switching to shorter cranks. Fulcrum height was the only way to adjust the saddle height. I made fulcrums at a few different heights, each one pinned to the frame so it drops in but can't rotate. Fine adjustments could be made by grinding one down or shimming it up. Yes, I admit it was dumb.
Mark B
Or just the two plates and bolts at the top can be used on a "seat mast" where the seat tube extends all the way to the saddle rails. I did that in 1977 on a race bike I made for myself. I'll admit the seatmast idea is dumb, and I winced when that design made a comeback. (when was that, early 2000s?) But I was 19 years old when I made mine, young dumb and full of...
Those are Weyless parts just out of frame at the top. They're not super valuable, but they ain't makin' 'em anymore. The tall fulcrum the weyless clamps sit atop was due to switching to shorter cranks. Fulcrum height was the only way to adjust the saddle height. I made fulcrums at a few different heights, each one pinned to the frame so it drops in but can't rotate. Fine adjustments could be made by grinding one down or shimming it up. Yes, I admit it was dumb.
Mark B
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Folks, this is 2023, and stuck posts aren't the nightmare that they used to be.
Muriatic acid dissolves aluminum.
Alkali solutions embrittle steel.
Some of us have found that cutting off 1" above the opening and using a slender, sharp sawzall blade can get any stuck alloy post out fast, with no damage to the frame.
The tricks are:
1) Begin by probing with a bent spoke to determine the inserted length of the post.
2) Make certain (by means of probing with a sharpened bent spoke) that the slot in the post is cut through to the steel all the way to the bottom of the post.
3) Do not align/clock the cut with the slot in the lug.
4) Do not let the blade contact the edge at the lug opening, so keep the blade's cutting side tilted slightly at all times.
5) Make sure that the end of the blade can't/doesn't reciprocate/travel too high and thus "catch" above the upper end edge of the seat tube, remembering that the directional teeth will tend to try to push the saw and blade upward as the blade digs into the aluminum and reciprocates through it's perhaps 1" of stroke.
6) The cut height doesn't need to extend much above the height of bottom of the slot in the seat tube, and doesn't need to extend to the end of the seat tube.
Please read the above (5) instructions several times, slowly.
Be patient and controlled with the cutting, especially when starting out, and again when extending the cut to just barely above the height of the lower end of the slot in the frame's seat tube.
If the teeth out near the tip of the blade clog, or seem to become dull, they can be directionally sharpened using a Dremel "wafer" disc using good technique. The leading teeth should do all of the cutting. Cutting oil on the teeth recommended, any oil will do.
Once cut through to steel, the post can be easily twisted out. For heavier amounts of twisting force using plumbing pliers, put a reinforcing insert such as a dowel into the ID of the end of the post. Back-and-forth action and WD40 should make this easy.
I've had to "slenderize" a Sawzall blade on the bench grinder to cope with the narrow ID of the post.
I've had to sharpen the teeth at the tip of a used blade.
There is no tendency for the blade to dig into the steel, unless you let the teeth contact the edge at the opening or at the slot.
It takes a lot of concentrated pressure to get a Sawzall blade's teeth to even start digging into steel, which is pretty much impossible to achieve at the tip of the blade.
Muriatic acid dissolves aluminum.
Alkali solutions embrittle steel.
Some of us have found that cutting off 1" above the opening and using a slender, sharp sawzall blade can get any stuck alloy post out fast, with no damage to the frame.
The tricks are:
1) Begin by probing with a bent spoke to determine the inserted length of the post.
2) Make certain (by means of probing with a sharpened bent spoke) that the slot in the post is cut through to the steel all the way to the bottom of the post.
3) Do not align/clock the cut with the slot in the lug.
4) Do not let the blade contact the edge at the lug opening, so keep the blade's cutting side tilted slightly at all times.
5) Make sure that the end of the blade can't/doesn't reciprocate/travel too high and thus "catch" above the upper end edge of the seat tube, remembering that the directional teeth will tend to try to push the saw and blade upward as the blade digs into the aluminum and reciprocates through it's perhaps 1" of stroke.
6) The cut height doesn't need to extend much above the height of bottom of the slot in the seat tube, and doesn't need to extend to the end of the seat tube.
Please read the above (5) instructions several times, slowly.
Be patient and controlled with the cutting, especially when starting out, and again when extending the cut to just barely above the height of the lower end of the slot in the frame's seat tube.
If the teeth out near the tip of the blade clog, or seem to become dull, they can be directionally sharpened using a Dremel "wafer" disc using good technique. The leading teeth should do all of the cutting. Cutting oil on the teeth recommended, any oil will do.
Once cut through to steel, the post can be easily twisted out. For heavier amounts of twisting force using plumbing pliers, put a reinforcing insert such as a dowel into the ID of the end of the post. Back-and-forth action and WD40 should make this easy.
I've had to "slenderize" a Sawzall blade on the bench grinder to cope with the narrow ID of the post.
I've had to sharpen the teeth at the tip of a used blade.
There is no tendency for the blade to dig into the steel, unless you let the teeth contact the edge at the opening or at the slot.
It takes a lot of concentrated pressure to get a Sawzall blade's teeth to even start digging into steel, which is pretty much impossible to achieve at the tip of the blade.
I'd add only that if you have any trepidation about using a Sawzall (or knock-off) consider what I use, sometimes: Stanley make a comfortable handle you can screw in any brand of "reciprocating saw" blade and do all the tedious work by hand!
It's not fast but has a lot more control and less chance of a novice going too far too quick! Bitter experience teaches: you can't put that metal back (not easily) once it's gone.
As dddd says, you often have to modify those blades to make them narrow enough for a seat post.
And I still have nightmares about some of those ridiculous struggles with "welded in" posts (and stems) of the past...