Rust removal techniques
 

I'd like to read how you folks have adressed the following situation: After some difficulty in removing a seat post from a 25 yr. old bike, I checked the seat tube and saw the rust inside the tube (HiTen steel). I'm interested in the techniques used to remove the rust on the interior of the seat tube.

Thanks,
Drew

Some of the ways are bulky and takes a lot of time. If your worried about ruining paint then you need to fill a tub large enough to submerge your frame in a bath of vinegar and let it soak for 72 hours. Or you can put a cork in the seat tube, turn the bike upside down and fill the frame with vinegar, but it will leak out so you have to stop the leaks, this process could take longer.

You can also buy rust removal liquid at auto parts stores (Naval Jelly) and pure this gunk down into the frame, but paint could be damaged.

OR; you can purchase a product for removing rust from the insides of steel tubes called Flex-Hone that may be still available from Loose Screws the mail order company. Then use Shooters Choice or Hoppies #9 to clean the rust out and lube the tubes. But these things can't get into the stays and forks.

Once you get the rust mostly out then use Frame Savor to arrest protect it in the future from rusting further.

search the forums for oxalic acid, lots of information on this and it works well

Two different and unrelated issues. Search for stuck seatpost on that topic, search for rust removal or oxalic acid on the internal frame rust. Hundreds of threads on either topic.

Step 1: Question whether removing rust from a 25 year old HiTen frame is worth the effort
Step 2: Slap the parts back on and ride it

Wrap some carborundum paper , ie sandpaper for metal, around a dowel, and sand off the excess rust .

grease the inside up your seat-tube and a little on the seatpost, and put it back together

Remember to remove and regrease the stem and seatpost and repeat. maybe annually .

How about using a product that removes rust via chelation instead of acid?

http://shieldtechnology.co.uk/rustremoval.html

(I have no experience with this product; a local retailer started selling this product which is how I know about it.)

Check the cost on it. Do the math on a 60 gallon bath of it, that's about the size of my frame bath. Lets see, one 500ml bottle for $40 US dilutes to two gallons. So I would need 30 bottles for a bath, $1200 worth. Right now, I use about $2 worth of oxalic to make a bath.

Did a little google search on this stuff, some report it to be very similar to using molasses, but paying a huge premium for it. There are a lot of people out there hawking this stuff.

Even if I could just use one bottle somehow, at the $40 price point, I would not bother doing most of the rust treatment I currently do. Just not cost effective.


MSDS on this stuff is straight from infomercial land. Pretty funny stuff.

Ah! The sweet voice of reason. It calls out, yet few
appear to listen. Or as in the zen: "I ride my bicycle
to ride my bicycle."

Mike Larmer

Thanks everyone for your responses. The seatpost was not stuck, I was able to remove it with a bit of "coaxing!" I thought about something like a brake cylinder hone, but I'll use the dowel and emory paper technique. Lube them both and stick them together! Clean the BB later.

Thanks again,
Drew

Drew:

As a footnote, you might consider using anti seize
compound (from the auto parts store) between the
post and tube. I pretty much use it anywhere I don't
want stuff to freeze up -- pedal to crank threads,
freewheel to hub threads, seat post, stem - you get
the idea.

Stuff contains lead thus toxic, so glove up at least a
finger prior to application. You don't need much.

Mike Larmer

Thanks for the anti seize suggestion! I've just been using Park Assembly lube. The bike's a Bridgestone Carmel ('85 or 86), really clean. Just obtained it. The seat tube doesn't have the usual binder bolt, the seat post uses an expander plug (like on the stem) to hold the post in position!

Drew

On an old hi-ten frame it's not so important to remove the rust as to stop it continuing to rust. Pouring a thick oil into the tubes and tip it around then drain to coat the entire insides will do the job just fine. Then reinstall the parts and go ride it.

You don't need to buy anti seize compound, simple grease thinly applied to both the the al post and the seat tube will prevent it from seizing for at least 5 years and prevent water seepage down the seat tube. Once every two years just remove the post and regrease. Wipe off any excess that oozes out., did I really have to mention that?

Thick oil will eventually drain and puddle in the bottom bracket area, Frame Savor does the same thing but won't drain down.

By the way, my oldest steel bike is 26 years old and there's not an ounce of rust anywhere either internally or externally and NOTHING has ever been used to prevent rust. BUT, if you want to be safe then be safe.

Depends on how you care for the bike. The big enemy is wet, usually from being left outside. Even if it doesn't rain, severe temperature differences can cause condensation. Putting the bike somewhere outside the direct weather will usually prevent most of this; I keep my steel roadster in a simple shed... It's been fine for years.
I made a simple rust-removing tool with a large-diameter dowel.... Cut a slot with a hacksaw and turned (actually carved) the other end down to fit my hand drill. Stick a couple of pieces of sandpaper into the slot so that the "sand" side always faces out...
Whirr away....

The seat tube is easy: Buy a 1/4" wooden dowel, slot one end and stick a piece of Brillo or Scotch-Brite pad in the slot. Insert the other end into the chuck of a hand drill, shove the slotted end into the seat tube and turn on the drill.

It's the other tubes that are tricky; you'll probably want to flush them with vinegar or dilute oxalic acid, followed by Frame Saver, linseed oil, or whatever.

Small brake cylinder hone works great just run it up and down a few times flush it out apply something you like to slow further rusting and good to go.
If you don't want to buy one use the wood dowel method but the brake hone is much faster.