Unfortunately while I was gone on a trip multiple people tried to ride my unicycle and it fell in my pool again and again without a thorough cleaning. I am trying to adjust my seat height and my seat post is completely rusted in place… I have also tried many kinds of lubricant to try to get in unstuck. Is there any place that I can send my unicycle into that will take it apart and give a thorough cleaning?
Did you try to spill Coke on it? I don’t know if it works, but some people say that it helps to unscrew rusty screws. But it was about a product called Kofola, I don’t know if it works with Coke. It’s similar, you can try it, I think you can’t do it any worse than now 
My guess is that between the frame and the seatpost one of them is steel, and the other is aluminum, and that there wasn’t any grease on the seatpost. If this is the case then the parts have galvanized together with the help of the electrolyte in the pool water. If my guess is right then I can offer one solution that works pretty well, and another that is faster but crude.
plug any holes in the end of the seatpost if there are any. Turn the frame over, and pour automotive antifreeze into the seat tube from the bottom. Let it sit like that over night, and in the morning you should be able to wrestle it free. If it doesn’t loosen up by the morning just repeat the procedure and try again the next day.
The alternative is to use a torch to heat up the frame, and break the bond, but that’s a bit aggressive.
If your seatpost is aluminum, and your frame some form of steel, or vice versa then it’s going to be tough getting out. When aluminum and steel corrode together, there is a chemical reaction between them, and they pretty much weld together.
Try taking the wheel and seat off the uni, leaving only the frame and seatpost. Put the frame in a vice or clamp, then use a pipe wrench to try and twist the seatpost free. If it doesn’t work, put lots of lube on it and let it soak in. Then try again, maybe with a pole on the end of the wrench for more leverage. When/if you get it out, use a wire brush and maybe sand paper to get the corrosion off. They also have some rust removing jelly. You could probably find some at a marine shop.
I’ve had to deal with this a few times where I live. It’s a bicyclist community on a very small tropical island. There’s lots of humidity, lots of windy, salty air, and lots of rain. It is probably the worst possible environment for metal.
How about some dry ice on the inside tube with boiling water poured over the outer?
if you can’t get it out by force cut the post off at the top of the frame then using a hacksaw blade with one end in something the protect your hand carefully cut slots in the post that is stuck in the frame making sure not to cut too deep and damage the frame which will enable you to get the separate sections out.
Also unless you have an expensive ride most frames are so cheap now (less than the tyre in some cases) I would have to weight up the effort and “value” of my time and probably just buy a new poet and frame, and would use it as an excuse to get something better 
You could just leave that one rusted in and it can be your loaner Uni to go in the pool again 
an get yourself a new spangly Uni (and don’t lend that one out).
[QUOTE=jtrops;1518106]
My guess is that between the frame and the seatpost one of them is steel, and the other is aluminum, and that there wasn’t any grease on the seatpost. If this is the case then the parts have galvanized together with the help of the electrolyte in the pool water. If my guess is right then I can offer one solution that works pretty well, and another that is faster but crude.
plug any holes in the end of the seatpost if there are any. Turn the frame over, and pour automotive antifreeze into the seat tube from the bottom. Let it sit like that over night, and in the morning you should be able to wrestle it free. If it doesn’t loosen up by the morning just repeat the procedure and try again the next day.
The alternative is to use a torch to heat up the frame, and break the bond, but that’s a bit aggressive.
Thank you! l will definitely try that. Do you know of any stores that sell automotive antifreeze? How much do you think it would be?
Thanks to everyone else for giving your ideas!
[quote=“unigy,post:7,topic:118057”]
You should be able to get it at any store that sells stuff for cars like a gas station, or auto supply store. It’s an additive for the cooling system to keep it from freezing in cold weather. It’s been a while since I’ve bought any, but it normally comes in gallon sized jugs in the $10+ range. Since you only need a pint or so you may be able to get it from an auto repair shop on the cheap, or free if you bring a bottle.
I’ve never tried ammonia, but I understand that it works as well, and it’s recommended by the late Sheldon Brown so it’s worth noting. You may have that in your cleaning cupboard, and you can get it in smaller bottles for much less.
[quote=“jtrops,post:9,topic:118057”]
So I would do the same thing except use ammonia?
Also does it have to be pure ammonia? Or would ammonia with other cleaning substances work? If it needs to be pure ammonia, where would I buy some?
You can buy ammonia at a grocery store or a drug store.
But are the post and frame different materials? If you have a magnet, see if it sticks to either or both. If it sticks to both (cheap uni with a steel seat post, for instance) then the stuff you want to use is a penetrating oil like Kroil or Liquid Wrench (Kroil is the superior product) for steel-on-steel corrosion. Set the uni up vertically and spray it on the seat post right at the point where the seat post enters the frame so the penetrating oil can work its way down the seat post tube of the frame. Let it sit a few hours or overnight. Then try to loosen it. If it doesn’t work, apply more and then heat the frame with a torch. Keep in mind, if you heat the frame with a torch the paint is going to be destroyed.
I cannot speak to the aluminum-on-steel corrosion removal techniques described above. I have, however, used the technique that I described for loosening a joint on a 90-year old, buried, galvanized steel water main.
Harper is right. Kroil is superior. Low heat will help the capillary action to get it to fully penetrate. High heat will boil the solvents, not necessarily a bad thing.
If my seat post is aluminum and my frame is steel with the Kroil oil still work?
Now that you know how to determine this, why don’t you find out?
If the seat tube is open at the bottom where it meets the crown, remove the wheel and place the frame on its side. Using a length of slightly smaller diameter steel tubing, place it inside the open end of the seat tube until it contacts the stuck seat post, then using a hammer, pound the seatpost back out.