What we call Cellulose in Blighty is in fact Nitro-cellulose the confusion comes in because across the pond they abandoned using it much earlier than we did here in the UK. Nitro-cellulose uses thinners, firms like Valentine's use to produce the thinners, however, a mate told me that you could in the past get a device called a "Hotpot", it had a kettle type element in it & you screwed into your spray gun, it heated up the cellulose so that it could be sprayed without thinners, in his words the finish was beautiful.
Nitro-cellulose can use as much as 50% thinners when applying the mix, thinners aren't exactly good for the environemtn & can be difficult to control when trying to get a uniform finish, with nitro-cellulose you build up your spray thinness by careful application of thin layers.
However, this is no excuse to have a drab coloured bike, which is visually displeasing, I could never understand the British manufacturers, giving bikes exotic names and then spraying them colours about as visually exciting as poo! Specialists, usually linked to restorations can supply special polishes and I presume protective coats that can be put over some finishes.
Nitro-cellulose may fade, oxidise, chip & scratch but it is re-touch-upable and can be "T"- cutted to a brilliant finish as many would know, the best non-fading pigments are greys and greens, usaully the drab colours, the worst for fade are reds & oranges, yellows, blue is somewhere in the middle depending on the shade of colour, this used to be the non-professional route for the home-restorer.
Metallic, polychromatic & pearlescent finishes are excellent for visible impact, legislation against cellulose paints came in because of volatile organic compounds, (VOCS) being released in the thinners.
Now we have paints like Two-pack acrylic enamel, replacing them, releasing isocyanates & which in process are more like Araldite-type hardener reactions in the way the components interact with one another, but full of of serious toxins, you need expensive cabin, ventilation, heating & breathing equipment to do the job without risking your health! Advantages, tough, relatively inert & extremely hard wearing
Apparently, there are/maybe some non-isocyanate hardened Two-Pack, which would eventually be ideal for the home restorer , someone out there may know where & how to get hold of them.
Good rust treatments in volume are hard to get hold of, Phosphoric acid is more difficult to buy these days because of Al-Qaeda's little exploits. The best black home finish I ever got on a frame, was a new synthetic gloss applied by a good quality paint brush, I heated the paint tin up in a bucket of boiling water, it was so black & shiny, when it reflected light from a distance it looked white, the only draw back was it was much softer than stove enamel, but it could be touched up on frame parts, problem is I can't remember who produced it, but people used to come up to me & asked what i had used to get the finish & were surprised it hadn't been professionally done.
Home restoration can be fun!
Cheers
John
JBW
