We spent several hours over the course of several days on a young woman's aluminum seatpost that was chemically bonded to her steel frame because of a lack of lubricant between the two.
We first used the torque of our palms to get the post to spin. Because it was a cheap seatpost that was two pieces of aluminum temperature bonded, it broke off at the top. We then gave it a healthy dose of helper fluid to break the bond. The fact is that the bond was from the bottom of the post to the top. After about a 24 hour soak, we went back at it. This time we drilled a nice clean hole in the post in order to insert a piece of tooling steel in there to get some nice torque. 2 of us with cheater bars provided in the neighborhood of 800 lb/feet of torque (I'm guessing here) and the post literally shattered. Our next idea was to open up a channel to get the fluid further into the frame by using a saw blade to slide a channel into the post. After about 45 minutes of this tedious procession, we had made a small slit part of the way down. The post still did not budge. We let it rest for a while with loads of caustic fluid hopefully finding its way to the chemical bonds. Our next idea was to put a quill stem inside the post, tighten it down and hammer it out. We quite literally broke the stem in half attempting to hammer out the post. (Some laughter may be necessary here) Finally, we decided to try reaming out the post from the inside out. We were going to attempt to shave the post to nothing. After a few hours of removing small amounts of post we made a call to our custom frame builder, James from Blacksheep. He explained that we would be doing this for many many hours and it may not work quite as easily as we were imagining. We decided to let the customer decide whether she could afford our labor or if we needed to call the project done.
I have to say that the young woman was both sad and understanding. She immediately saw the bright side of the situation, that being that her next bike will be fully adjustable and will have a nice slippery seatpost.
By the way, she bought this bike at VeloSwap. Yet another word of warning about buying from an unknown source. Check to make sure the seatpost was greased.