About a year ago I picked up a 1985 Panasonic Pro-ATB for my son. It's a great bike unfortunately the seatpost is stuck. It won't budge no matter what I try. So the bike has sat in the garage untouched. I was looking at the frame this morning and realized that this would make an excellent touring bike, much better than the Diamondback Ascent I'm currently working on. I decided to make one last all-out effort to remove the seatpost. I'm thinking about trying the caustic soda method (CS for short). Basically you pour CS down the seattube (for me it will be from the bottom bracket while the frame is suspended upside down). The CS dissolves the aluminum seatpost, sparing the steel frame. The problem with this method is that the chemical reaction between the aluminum and CS produces a lot of heat and poison gas (ask any meth cook). This method works but you've got to be really careful. I stripped the frame but discovered that the bottom bracket shell is stuck. It's sitting at the shop right now. I hope to have it back tomorrow. I'll be heading to the hardware store to pick up CS, plastic tubing, and safety gear.
How NOT to do the CS method. The first three minutes are pretty entertaining.
I hope you can come up with an alternative to the CS method. I'm not afraid to take things apart because I know that if I'm paying attention (and make notes or draw a diagram) I can put them back together. But chemicals scare me. Chemicals, and electric stuff.
ReplyDeleteThe Diamond Back is good, but I think the Panasonic will be even better. I assembled many Panasonics and was always impressed with them. However, to this day, people say, "Really? Panasonic made bikes?"
Have you soaked it in Marvel Mystery Oil for a week or two? One other thing to keep in mind is tha aluminum will shrink quite a bit when cold (as in dry ice), whereas you can pour hot water over the steel tube.
ReplyDeleteIs there a machine shop, nearby? It might be safer to have them cut the seat post and them ream it out of the seat tube...
ReplyDeleteWell, I'm going to try to find a machine shop that is willing to mess with my frame. The caustic soda will most likely damage the paint. If a machine shop can't help me, the chemical reaction/ poison gas method will be tried.
ReplyDeleteHi - great bike and I hope you get your seat post out. I bought a frame of the exact same model and had it powder coated to build up as a touring bike. I want to add replacement decals to mine and I'm wondering if you could post or email a close up of the graphic on the side of the seat tube and where the Tange label is on the seat tube? - Thanks and good luck with yours.
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