Hallo, i have got rusty urban frame form 60s maybe 50s, i wonder if it is possible to leave all that rust and only to protect it (with some transparent paint - i think) from further rusting?, other thing are frame hooks, they are in bad condition, is there any simple solution to fix it?, i do not want to restore this frame, so this solution can also be non standard, by the way, someone knows what type of bottom bracket is in that bike? i see it for the first time, there is also a pin in frame to block it - if i think well.

That frame might be a little older than you think.

If you want to keep the current look with a few concessions, I would start with a rust convertor. Most hardware stores will have this as in spray can or possibly brush on liquid. It converts the rust into an inert patina in preparation for painting. If you can get the convertor in a can, you might want to get it inside the tubes as well. The final color of the rust will be a very dark brown. Too thick of a clear coat makes the bad paint and rust look plasticy and usually awful. Don't use anything from the hardware store. Unless you can get a professional clear coat done, I would just use a paste wax.

Others will know more about the bottom bracket, but I would just start pulling it apart, carefully. You will also need to straighten out the fork tips and "track" ends.

Have fun with it.

That frame is from 1910-1920 or so. If you aren't used to working on bikes, take it a little easy. That old girl is fragile.

It may be difficult to find parts to fit that frame.

Looks like a prime candidate for an OA bath. (And I know nothing about bikes that old, but it certainly looks much older than the 50s.)

It would great to see any markings on the parts, names, logos whatever. I would like to see a photo of the head light bracket (on the steering stem)

Thanks

I like to scrub these frames with steel (or preferably Bronze) wool dipped in linseed oil. Wipe off the excess and it looks great.

unfortunately I do not have nothing but a frame, i have also examine it carefully and i have not found any logos or numbers,
from seller i know that it could be a german bike, i searched around 10' - 20' as you suggested and i have found Göricke Nero Damenrad 1925 but not everything exactly match

my idea for this bike was to leave only rusty frame and composed all other parts from new chrome and shiny, but maybe such old bike is better candidate for restoration

some of the older bikes take a long time to find a match,
I had a bike 3 years before I figured out what it was.

I agree that it is a European bike but there are many clues. Things like the bolt sizes and small stampings on internal parts are clues and it does take a lot of research. Taking many good photographs, uploading them and showing them around may be a great help. There are a lot of people viewing these threads and inquiries take time.

I don't know anything about your bike yet but I did some searching on American and British brands and found Columbia and Raleigh models that are close also.

i took some detail pictures