kawaray

Hi,

I just picked up a vintage steel bike from its original owner, so I stripped all the components off to start the rebuild. The bike was relatively well maintained, but has been put into a good use over the last three decades (it sounded like it was a commuter bike, including in the winter, as evidenced by the studded tires that it came with). So, there are some rust. It is nothing terrible, and is hardly noticeable, except on the chain stay bridge (I believe that this won't concern any structural integrity of the frame). When I peeked inside of the seat tube, there is a bit of rust layer, but I don't believe that it is eating deep into the wall.

I am interesting in giving the frame a good care before commencing my rebuild. I was going to apply frame saver inside. I was also going to apply clear coating (I usually use clear nail polish) over the rusted area. Are there anything else I could/should try?

Chicago Al 

Rust--removing and preventing it--is a topic that comes up again and again in this forum,so I suggest you do a search for previous threads about it. A few favorite methods here for removing active rust are 'rust converters,' chelating products like Evaporust, and acid treatments like oxalic acid aka OA or vinegar.

kawaray

Ohhh, of course! I will do the search to find older posts. Thanks!

Chicago Al 

BTW the search function here can be frustrating; I find that logging OUT of BF makes the advanced search function work better for me.

albrt 

A lot of times I can find subject matter threads easier using Google than on the Forum search function.

kawaray

Thank you both! I found a few threads that were helpful, and went ahead and bought evapo rust and a rust converter spray to give them a shot from a local hardware store. Thanks!

Aardwolf

Try googling for something like

SirMike1983 

You have three basic ways to choose from: chemically remove rust, abrasion, or electrolysis. Each has its strong points and weak points.

Evaporust and Oxalic Acid are popular ways to chemically remove rust. These methods are nice if you have a paint that will not react with them, and you want to remove a lot of peppering and small rust spots that are hard to remove through abrasion. Both workl with certain kinds of paint, but can damage paint as well. Green, blues, and whites often are OK. Red paint can be a problem (can bleach to pink). Certain gold paints and accents bleach to silver or white. Certain paints with aluminum in them can flake and separate. Evaporust also can ruin old water slide transfers by softening them. Oxalic acid can bleach or soften water slides if left in long enough. Test the solution out before using this method. Evaporust may be prohibitively expensive for dipping large items like fenders and frames. If all works out, you'll be left with paint and bare metal spots. You'll need to treat or fill in the bare metal areas that are left, which can be very time consuming. You'll need to clean out and dry the interior of frame and fork tubes.

Another option is to abrade the rust away gently using bronze wool, ultra-fine steel wool, and something like WD-40 or similar. Some paints will scratch badly using this method (older clear coats are probably the worst with it), but some respond well. This method tends to work if you have a durable paint and a general peppering where you want to remove a large and thin area of rust staining. Don't touch the transfers/decals. You'll probably need to polish afterward to remove any fine marks from the wool.

Electrolysis can work but you need the set up for it, and most home mechanics won't have a set up to do a frame or large parts like fenders. It's worth looking into a set up if you're going to be doing this a lot, and need to just keep turning out cleaned items.

I did a head-to-head comparison of abrasion vs oxalic acid on fenders from a 1930s era Cadillac branded bicycle made by Cleveland Welding Company. The WD-40 and 0000 steel wool turned out a fender with a more consistent overall presentation but with less thorough rust removal. The oxalic acid turned out a "cleaner" fender, but the condition was less consistent overall in that there was paint and then stark bare metal. Both were marked improvements over how they arrived.

https://bikeshedva.blogspot.com/2015...alic-acid.html

Vintage Schwinn

I think SirMike1983 has given you a great summary of all of your generally accepted choices.

There is a somewhat unconventional method that might work okay in certain situations (it should work okay, although I have used the exact specific product on several automobile projects in the 1990's and in the early 2000's as well as other projects....)

Specifically, the product that I am referring to is known as POR-15, though other companies such as Eastwood, I think probably purchased the license-rights to issue basically the same stuff under their own house brand.

It is a "paint like liquid" that permanently bonds and encapsulates the rust, and it adheres best to really rusted steel that has not been cleaned up(treated/sandblasted/or taken back to clean metal ).
..........................Now POR-15 , I think the POR-15 "painted"(coated) rusty metal will typically have some degredation if it will be exposed to direct sunlight/UV rays, thus unless the coated rusty metal is hidden from view, I think you have to top coat it with some sort of suitable paint, but as long as sunlight and UV rays don't reach the POR-15 coating, then there is no need to top coat it with any paint.
POR-15 is fairly expensive compared to traditional rust treatments.
You don't want to purchase more than you will immediately use because due to the nature of POR-15, you'll never get the can to open ever again.

Many years ago, POR-15 worked tremendously well at solidifying the INNER ROCKER PANELS of a late model Corvair convertible. GM in its infinite idiotic wisdom innovatively produced what it termed "FLOW THRU ROCKER PANELS" on a number of vehicles in the mid to late sixties. On paper, the theory behind it was great but in real world conditions it proved to be a horrible design because water, pine straw, leaves, decayed leaves, dirt etc would inevitably get past the window rubber and accumulate within the flow thru channel of the flow thru rocker panels. The idea was that owners or even dealer service dept could simply remove the tightly fitting rubber plugs at front and rear wheelhousings at the rocker panel ends and then use a garden house with adequate water pressure to flush out all the accumulated crap on a relatively frequent basis, that the rocker panels would survive better and longer than other cars of that era. Bear in mind that in those days, there wasn't any rust proofing or galvanizing done on inner panels as you have today. AMC-Rambler was perhaps one of the first in about 1963 but others didn't until well into the seventies.
Still that idea on paper was good but folks never did any thing and those living in the snow belt saw road salt rot small openings within the first winter that would catch more debris and crud, thus that the inner panel would be like the worst rats nest or the worst ever clogged gutter....
.................The rocker panels are a SIGNIFICANT structural component of the unibody Corvair convertible.
Well the Corvair clubs and later their forums would prescribe cleaning as much pine straw and leaf/accorn dirt debris from the rocker panels using golf club shafts/coat hangers/and metal rods and fishing rods and a piece of bamboo cane pole or whatever.......... One clever way was to attach a multiple fish hook like end to a True Temper golf club shaft taken or cut from a junk/old club.
.......Then the Rx (prescription) was to take the Corvair and park it on at least a slight hill on a dirt driveway, street, etc, as not to mess up a nice driveway.....
You then attempted to get as much POR-15 into the inner rockers.
That POR-15 coating stuff will stiffen a heavily rusted piece of metal that currently is flimsy from decades of rust attacking and removing much of the metal.
It is extremely messy, and it will not come off of your skin........it will only wear off of your skin within approx one week to ten days.....
.......................Now, you may wish to consider possibly how much of such a coating of POR-15 would add in WEIGHT to your bicycle frame.
I would imagine that such an amount of added weight would be immaterial if we are talking about some Cleveland Welding Company "cruiser" from the 1940's with its other heavy accessories such as the steel bolt on tank, and the heavy stamped steel rear rack, not to mention if it has one of those do nothing, springer fork attachments that folks thought looked neato but was functionally a useless piece of crap............So yes, on such a 65 pound bicycle if you're adding, I just guessing here, perhaps maybe a 1/2 pound or so in weight if you were to use POR-15 to coat the inside of an old steel frame.
Now certainly you might not need POR-15 or any type of inner frame coating for that matter because I am certain that you likely probably don't have any rust areas on the exterior, and the factory paint is likely in excellent condition with no exhibited areas with any rusted or pitted areas.
A few of the CABE people sometimes are quite a different breed, where some doofus will not hesitate to ride some massively rusted hunk o junk that looked like it sat in a garden rusting in place since 1954. I'm not making this up, there are some that are so bonkers that they will ride some ancient very rusted bike because it was from their birth year or because it was made from before the start of World War II. Fortunately, those cruiser , coaster brake single speeds typically only cruise at perhaps at 7 to 11mph so when some severely rusted frame tube breaks nearly in half while they are riding it without a helmet that they won't be injured so badly that they need a Life-Flight helicopter ride to the nearest Trauma Center. Those same doofuses also love to proclaim that the bike is riding on the original 1946 US Royal tires made in Akron Ohio, but they don't seem to be concerned that those tires have petrified rubber that has many massive cracks and it is missing chunks and those nearly 80 year old aged decayed tires now have the flexibility of a brick.


Anybody have any idea if there is any practical use for POR-15 for bicycle use? Has anybody tried it on any bicycle project?

I think SirMike1983 's summary mostly sums it up. My guess is that if you have such a rusty bike that ordinarily one would seek out a less rusty or nearly rust free frame, unless you're one of those that says well its a 1936 Western Flyer that the work crew who installed a swmming pool next door, found it buried in the ground, when they dug up their backyard to install the new swimming pool. Something like that... because if you really need POR-15, perhaps it is more cost effective and smart to find a clean non rusted frame of the same size and year make- model as that will certainly give your build-a -bike project that best starting point

kelbype

I think Evoporust or Kurust works well for rust spots on paint. After you wash down and scrub the bike apply the solution. It works well also if you intend to touch up some of the small spots with an enamel paint too.