How do you guys bust rust this bad?

[Bike from the Dead]

Plug the seat post. Turn the frame upside down and fill the seat tube with either citric acid mix, or atf / acetone thru the hole in the bottom bracket.
That amount if crust may be worth acid treatment, then penetrating oil.

I might do that. I've been hitting it with PB Blaster on-and-off for the past couple months, but I don't know if it's penetrated the rust at all. I've just kind of stalled on this one because I've been working on a few other bikes, and I need the bike stand to work on those. I'll figure something out. I'm in no hurry.

 

[rat krate orange]

I might do that. I've been hitting it with PB Blaster on-and-off for the past couple months, but I don't know if it's penetrated the rust at all. I've just kind of stalled on this one because I've been working on a few other bikes, and I need the bike stand to work on those. I'll figure something out. I'm in no hurry.

WOW, You don't know how lucky you are.. I guess i'm just to old skcool because I've never even owned a nite stand.. Built all of my bikes with a LARGE and small bench vice is the closet thing i have to a stand... Good luck... Razin...

 

[curtisfox]

To help the PB put some acetone with it helps it get down in further. he ordinal mix is 50/50 acetone and ATF, but acetone evaporates so fast, I have also used brake cleaner to help, the pentrating oil go deeper........Curt

 

[us56456712]

I’m working on similar rust encased project right now. It’s currently soaking in penetrant in a warm basement. I might use my firecracker idea in the head tube. For the bb I’m going to try my big Bosch hammer drill with the bit on a block of maple hardwood. Hopefully the vibration will bust the rust. I’ll also use my son and son-in-laws muscles, their young and a lot stronger than I am.

 

[Ulu]

Before I'd beat on it hard, or put explosives in a valuable frame, I would consider heat and vibratory methods. This will advance the action of the oil, along the length of the post.

Which is the issue. Oil must seep into a crack the length of the post, from the ends in. Like 3" each way.

That action slows as the square of the distance. Double the distance= 4x the time.
4x dist= 16x time

If the oil seeps in 1/2" in a day, the second day it will go 1/4". third day 1/8". 4th day 1/16" 5th day 1/32". 6th day 1/64"

How long does the oil take to go 3". In 6 days it goes 63/64" in this (what-if) case.

next week: .0075 + .00375 + .001875 + .00094 + .00049 + .00025 + .000125 = less than 1/64"

It's like Zeno's paradox. Can't get there, from here, that way.

After 2 weeks it soaks almost 2" of the theoretical 6". Just 1" from each end

BUT repeated heat cycles and vibration will speed the process A LOT.

 

[Ulu]

To help the PB put some acetone with it helps it get down in further. he ordinal mix is 50/50 acetone and ATF, but acetone evaporates so fast, I have also used brake cleaner to help, the pentrating oil go deeper........Curt

I switched from PB to Deep Creep, which has some acid in it. That's what I used to flush my muddy Sturmey hub.
The rust and mud neutralizes the acid, as the acid dissolves the rust and mud.

 

[SpokeMan]

an oxy-acetylene torch and a pipe wrench! I know not every one has access to one, I don't anymore either. A weld shop would be able to un stuck that for you.

 

[Bike from the Dead]

Those are all definitely good suggestions, but I really want to avoid using heat on the frame, because I don't want to mess up what's left of the original paint. The paint's what makes this frame special, as it proves that this frame was once a Black Phantom. The frame itself is a little too far gone for a full-blown restoration, at least in my opinion, but I think it's good enough to build into a rideable state. I just don't want to scorch the paint too bad. There's not much left to scorch, but still!

 

[Bike from the Dead]

What about naval jelly? Would that be able to bust the seat post loose without using a torch?

 

[SpokeMan]

Naval Jelly is worth a shot. Does the serial number notate the model? I suppose you could try running a hacksaw blade along the inside of the seat post until you make it threw the seat post and then us a chisel or probably a long heavy duty flat head screw driver and chisel it out. Id probably hack saw it 2-3 times down the length of the seat post. Its very labor intensive, wear gloves!! I also see your stem is stuck in the fork, again easiest quickest way would be the torch and pipe wrench.

 

[SpokeMan]

Ive done the hacksaw thing a few times because i didnt have access or the money for the weld shop. It is a lot of work with the hack saw, and i guess you are limited by the length of the blade. You'll have to use just the blade, ( so it fits down inside the seat post) maybe you have a key hole saw that might work for a handle? You will need to cut the seat post step down off, and as close to the frame as possible so you take advantage of using as much of the length of the saw blade as you can. I wrap duct tape on one end as a handle and wear some leather work gloves. the idea is to cut the seat post length wise from the inside out, with out cutting into the inside wall of the seat tube, then chisel it out in pieces. You may need to also pick up a six pack of your favorite brew to help alleviate some of the frustration and the hand and forearm cramps LOL

 

[skylonda]

An associate of mine once saved a valuable Miyata frame by gently heating with a propane torch, then plunging just the exposed portion of the stuck post in a bucket of ice-filled water. You may be reluctant to use heat, but that area will be covered by the seat clamp. Anyway, expansion-contraction is another idea to explore.

I’ve separated amd assembled parts many times using thermal shock - it works better when it is different materials like a steel frame with an alloy seatpost. More extreme sudden temperature change can be achieved with liquid nitrogen.