a vise is good for stuck seat posts. flip over the bike, insert seat post into vise, tighten -but not too much to crush post-, move bike frame back and forth gently and smoothly while pulling up. be very careful to use smooth motions and 2 or 3 people as to not tweak frame.
any other 'stuck seat post' tips?
-Bob Giordano, Free Cycles Missoula
On 6-Aug-08, at 10:37 AM, Bob Giordano wrote:
a vise is good for stuck seat posts. flip over the bike, insert
seat post into vise, tighten -but not too much to crush post-, move bike
frame back and forth gently and smoothly while pulling up. be very careful to
use smooth motions and 2 or 3 people as to not tweak frame.
Yeah, we have a 4" vise and it has come in very handy for things like
this. It of course also needs to be bolted to a strong, sturdy table.
any other 'stuck seat post' tips?
-Bob Giordano, Free Cycles Missoula
Sheldon has the answer(s):
http://www.sheldonbrown.com/stuck-seatposts.html
Cheers,
Mark Rehder http://re-cycles.ca
speaking of vices, i took a welding class recently at our local state university. the teacher has been around for a long time, and has a ton of old tools and equipment, including machine shop tools, anvils, vices, etc. he advised us to never buy a vice (or an anvil, but that's beyond the scope of this discussion) new, since good quality ones can last over 100 years. as evidenced by the two 100+ year old vices and anvil we had and used in the welding/machine shop.
he suggested going to artisan welders more than production type welders, as they tend to have leads on older, more robust, used equipment.
On Wed, Aug 6, 2008 at 9:22 AM, Mark Rehder mark@re-cycles.ca wrote:
On 6-Aug-08, at 10:37 AM, Bob Giordano wrote:
a vise is good for stuck seat posts. flip over the bike, insert seat post
into vise, tighten -but not too much to crush post-, move bike frame back and forth gently and smoothly while pulling up. be very careful to use smooth motions and 2 or 3 people as to not tweak frame.
Yeah, we have a 4" vise and it has come in very handy for things like this. It of course also needs to be bolted to a strong, sturdy table.
any other 'stuck seat post' tips?
-Bob Giordano, Free Cycles Missoula
Sheldon has the answer(s):
http://www.sheldonbrown.com/stuck-seatposts.html
Cheers,
Mark Rehder http://re-cycles.ca
Thethinktank mailing list Thethinktank@bikecollectives.org
http://lists.bikecollectives.org/listinfo.cgi/thethinktank-bikecollectives.o...
Vice advice is right on - posting an ad for a good ole vice for a community bike shop could get one donated. Lots of folks with unused shops out there.
The other thing to try on a seatpost is to take the bottom bracket out, put the frame in a stand and flip it upside down, then drip some penetrating oil in the seat tube. This takes some time, but worth trying before in there with a hacksaw or risking damaging a sweet frame by pounding & wrenching.
- Colin
On 8/6/08, Mark Rehder mark@re-cycles.ca wrote:
On 6-Aug-08, at 10:37 AM, Bob Giordano wrote:
a vise is good for stuck seat posts. flip over the bike, insert seat post
into vise, tighten -but not too much to crush post-, move bike frame back and forth gently and smoothly while pulling up. be very careful to use smooth motions and 2 or 3 people as to not tweak frame.
Yeah, we have a 4" vise and it has come in very handy for things like this. It of course also needs to be bolted to a strong, sturdy table.
any other 'stuck seat post' tips?
-Bob Giordano, Free Cycles Missoula
Sheldon has the answer(s):
http://www.sheldonbrown.com/stuck-seatposts.html
Cheers,
Mark Rehder http://re-cycles.ca _______________________________________________ Thethinktank mailing list Thethinktank@bikecollectives.org
http://lists.bikecollectives.org/listinfo.cgi/thethinktank-bikecollectives.o...
Our head mechanic has had success with soaking seat-posts with Coca Cola (frame upside down; plug the end of seatpost if it's a straight post; you might have to remove the bottom-bracket for this or if the frame has water-bottle bosses on the seat tube you can inject/ pour thru those). This takes time but works on frames where the post is seized in the frame due to metals reacting with eachother and not rust. Don't use this with carbon, only aluminum/ steel frames. Also, using ammonia is another trick but beware that it can cause aluminum to expand, so you need to understand your metals (steel frame? Steel post?). Another one is using cold temps (ice, compressed air, etc) to get the metals to shrink/ expand.
Tim
Tim Potter Coordinator MSU Bikes Service Center B10 Bessey Hall/ Michigan St. University Along the N. River Trail, 300 ft. west of Farm Ln. Bridge E. Lansing, MI 48824-1033
Ph: 517/432-3400 Fax: 517/432-2743 Email: mailto:bikes@msu.edu bikes@msu.edu Web: file:///C:\Documents%20and%20Settings\tbpotter\Application%20Data\Microsoft \Signatures\www.bikes.msu.edu www.bikes.msu.edu Home Dept: file:///C:\Documents%20and%20Settings\tbpotter\Application%20Data\Microsoft \Signatures\www.transportation.pp.msu.edu www.transportation.pp.msu.edu
From: thethinktank-bounces@bikecollectives.org [mailto:thethinktank-bounces@bikecollectives.org] On Behalf Of Colin Dixon, Phoenix Bikes Sent: Wednesday, August 06, 2008 12:18 PM To: The Think Tank Subject: Re: [TheThinkTank] stuck seat post tip
Vice advice is right on - posting an ad for a good ole vice for a community bike shop could get one donated. Lots of folks with unused shops out there.
The other thing to try on a seatpost is to take the bottom bracket out, put the frame in a stand and flip it upside down, then drip some penetrating oil in the seat tube. This takes some time, but worth trying before in there with a hacksaw or risking damaging a sweet frame by pounding & wrenching.
- Colin
On 8/6/08, Mark Rehder mark@re-cycles.ca wrote:
On 6-Aug-08, at 10:37 AM, Bob Giordano wrote:
a vise is good for stuck seat posts. flip over the bike, insert seat post into vise, tighten -but not too much to crush post-, move bike frame back and forth gently and smoothly while pulling up. be very careful to use smooth motions and 2 or 3 people as to not tweak frame.
Yeah, we have a 4" vise and it has come in very handy for things like this. It of course also needs to be bolted to a strong, sturdy table.
any other 'stuck seat post' tips?
-Bob Giordano, Free Cycles Missoula
Sheldon has the answer(s):
http://www.sheldonbrown.com/stuck-seatposts.html
Cheers,
Mark Rehder http://re-cycles.ca http://re-cycles.ca/
Thethinktank mailing list Thethinktank@bikecollectives.org http://lists.bikecollectives.org/listinfo.cgi/thethinktank-bikecollectives.o rg
Method below works better on a steel post (on which you can safely crush the end if it is a few inches out of the frame). Soak steel posts with penetrating oil (dribbled in over several days). A sharp rap with a steel hammer may help break the corrosion loose.
According to Sheldon Brown's website the only way to dissolve an aluminum/steel corrosion bond is with ammonia (haven't tried it myself). Tried putting my alloy post in a vice but it was too brittle and just cracked and disintegrated. So I have resorted to cutting it off and attempting to cut a slot with a hack saw blade. Naturally the post is inserted a good 12 inches in to the frame :-( Once the slot is cut I'll try to twist it out or break it up (or at least clear the first 3-4 inches so I can insert another post.
BTW if dealing with an oversize frame/seatpost, I simply cut off the post flush with the frame, cut a short slot in the old post (matching the one in the frame) and then find a smaller post to fit inside the old post.
PPS I'm not the dummy that put an alloy post 12 inches in to a steel frame with no grease. I am however the one that salvaged a sweet Pinnerrello (sp?) from the garbage (complete except for wheels, chain, rear derailleur and a seat).
Chris --- Bob Giordano mist@strans.org wrote:
a vise is good for stuck seat posts. flip over the bike, insert seat post into vise, tighten -but not too much to crush post-, move bike frame back and forth gently and smoothly while pulling up. be very careful to use smooth motions and 2 or 3 people as to not tweak frame.
any other 'stuck seat post' tips?
-Bob Giordano, Free Cycles Missoula
Thethinktank mailing list Thethinktank@bikecollectives.org
http://lists.bikecollectives.org/listinfo.cgi/thethinktank-bikecollectives.o...
participants (6)
-
Bob Giordano -
Chris Wells -
Colin Dixon, Phoenix Bikes -
Mark Rehder -
Tim Potter -
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