A friend totally mangled a seat post (that he hadn't lubed properly. Shame!) on a steel frame, got frustrated, and gave me the frame for cheap.

I took it to my LBS and they recommended taking a hacksaw blade and sawing up and down for a while to notch the seat post. Then, theoretically, once a couple of notches had been made, slivers of the post would come out and it could be removed that way.

Well the thing was rusted in there really firmly. So after notching the thing all the way around and not getting any movement, I started to try to hammer it down. Needless to say, it's still there.

Any thoughts on how I could get it out? Or, if I hammer it down far enough will I be okay?

Thanks for any responses.

how about a seat tube reamer on the inside of the seat post? grind away at the inside of the post until you hit the frame, just a crazy thought.
is the post aluminum?
what kind/brand of frame, have to know to see if it's worth the trouble.

It's an IRO Mark V; alloy seat post. I can't really do much more sawing/grinding since the slivers are now bent down.

Well, your options are scarce seeing as how the post is bent in on itself. Basically, the only thing you can do now is fixture the frame up in a (horizontal) mill , and feed the whole thing into a cutter either the exact st id or slightly smaller. The set up is crucial, or you will scew the st up. The tube needs to be exactly on center with the tool. It would take someone with some machining experienece to do it right. The set up needs to rigid, and the feed slooooow.

Resist the urge to pound a screwdriver down in b/t the post and st.. it will bulge and tear the st.

several bike shops send frames to me to remove seatposts, I use a counterbore with a center pilot custom turned to the inside of the seatpost so it won't veere off and hit the seat tube, usually leaves a thin sleeve inside and I use a small chisel to cut down the length of the remaining alum. tube, usually falls out after that

at this point i would ream it out. start small, and increase till you hit the seat tube, or near enough you can bend the post out. ive also heard that amonia will help break down the al. but that could be a total load, ive never not been able to just force the thing out. also, if you can get a seat tube colar around just the seat post, clamp the **** down, clamp the colar in a vice, and use the frame as leverage to twist the post out. good luck!

Reaming is a bad option because it really isn't designed for mass removal of material, but it may appeal because it can be done by hand or with simple machines. Consider a cheap adjustible reamer:

https://www.victornet.com/cgi-bin/vic...90&id=UMwSawtD

If the post bits are mashed inward, the above few suggestions won't work....

or if there's anything left sticking out of the frame you could drill through the seatpost and put a bolt through it to put in a vice or something

couldn't you just drill through them or cut that section off? a pic form the OP would sure help...