Best paint for DIY bike restoration

[rowan.bradley]

I need to repaint my frame, oil tank, toolbox, petrol tank and probably other parts as well. It seems that the "best" sort of paint is two part polyurethane, but there are frightening stories of how poisonous this is, how I have to use a pressurised mask, and how much care must be taken when using it, which has put me off. I understand that I can use 1-part paint, but I've been told that if I use this on the petrol tank I will need to cover it with two-part lacquer, which gets me back into the same scenario. What is the recommended sort of paint that can safely be used at home by a careful DIYer? I can either brush paint or spray. Are there techniques that will allow me to use two-art polyU safely at home? Are there other sorts of paint that will do a good job but are safer (when I last got involved with this sort of thing, everyone used cellulose)? Do I have to get a professional to do it for me? More expense and less DIY satisfaction...

Thanks - Rowan

[BSA_54A10]

I start with POR 15 on bare sand blasted steel, 2 coats left a full day between them.
After that whatever top coat you like.
I use plain enamel cause it is easy to repair and if you get the black POR 15 chips do not show.
By going this way the frame will never ever rust even if left fully under water, well the outside will not rust any way.

Back in the old days it was plain brushing enamel diluted about 20% with Penetrol which gives a better finish off the brush and no brush marks.

Now days I spray the top coat with a touch up gun.
Frames get 4 to 6 coats sounds a lot but a 4oz gun will just about do the frame twice.

[lawnmowerman]

POR 15 is great. Can be a little tricky to brush as it is quite thick so I pour enough for one coat in a jar and add a small amount of POR thinners then leave it in the sun to warm slightly - clean jar for every coat to avoid dust particles accumulating. If I can I also leave the job in the sun to warm a little. Dries to a great smooth finish but as Trev says, a full day between coats or it will drag.

I have also found that Hammerite smooth black gloss spray cans are great for small parts - only half hour between coats so easy to get four coats on and dry ready to fit the next day.

Jim

[terryg]

Black POR 15 worked for me 4 years ago.  I bought a six pack of small (4 US ozs) tins, in order to minimise wastage once a tin is opened.  There's 1 unopened tin left after painting the bike frame and a few other bits including oil tank and tool box.
I also bought about 2 litres of their thinners, most of which I still have.  I sprayed in the open at lowish pressure (sorry I can't remember exactly what) and it gave a good finish from the gun.  Washing the gun out with standard celly thinners as soon as possible did not prove to be as difficult as I had expected.

The frame and bits were wire brush, paint stripper and scraper cleaned - not blasted, which would have been a whole lot quicker and easier.  A wipe over with celly thinners and drying bits before spraying seemed to work OK.  Pre-paint would have been even better, I expect.

The finish I got was perhaps even better than I've had with 2 pack paint.

I've read about the need to overpaint POR 15 with a top coat paint type to improve UV resistance but I did not do this - as the bike gets little use and is always stored inside.

I'm still happy with the result but I may not be as particular as some.

Edit - I used 2-pack for the tank, amongst other things.  I use an air-fed mask and take a lot of care not to expose neighbours to any fumes.  Great care when mixing is necessary - use the mask then too!  It's the activator that causes the problems.  Until you open that up you are (relatively) safe.  Just remember too that inhaling quantities of anything but fresh air has risks.

[rowan.bradley]

I am planning to use POR15 for the frame but it only seems to be available in one or two colours, so for the colour of my choice on the petrol tank I guess I need to follow terryg's example and use 2K paint for that. I'm not sure whether it's cheaper to buy an air fed mask or to have the tank painted professionally. What is the cheapest air fed mask that's adequate? Can it be fed from my normal air compressor (which contains oil) at the same time as feeding the spray gun? It's a 9.6cfm compressor.

What other precautions do I need to take to use 2K paint safely?

Thanks - Rowan

[terryg]

Almost certainly cheaper to have a local body shop paint your tank unless you want the option of future use from the kit.  Others will advise on top quality tank repainting but pop in to your local refinishing shop and make some enquiries, is my suggestion.

Your compressor is a good size but air fed masks do use a lot of air - and require a high quality oil mist filter to reduce risks, unless fed from an oil free compressor.  My 2 hp compressor struggles if I use the recommended mask flow rate.

[jachenbach]

In USA, you can get spray cans filled with paint,reducer, hardener at auto paint supply shops.

[Joolstacho]

You have a good mask. Use 2K SS Satin black (SS - Single Stage means you won't need a clearcoat). IMV satin looks more authentic than gloss.
Then for the colour parts use basecoat and 2K clearcoat. 2K is harder quicker and is more impervious to chemicals, petrol etc.
Work in a covered outside area on a still warm day. The amount you're blowing (it ain't a car) is not enough to worry the neighbours.
I've been doing bikes and guitars for many years like this.

[rowan.bradley]

What is "basecoat"? Does that need to be a 2K paint? What technology does it need to be? Does it have to be polyurethane? Who do I buy it from (I need someone who will let me select a colour from colour charts. I am not trying to match an original colour).

Thanks - Rowan

[terryg]

My (limited) understanding is that basecoat is a colour coat that requires a lacquer finish (1K or 2K, take your pick).  Often nowadays the basecoat is a water based paint.
My local car paint supplier has a vast range of colour samples that I can choose from - on the back of each sample card is the type of paint and the code for mixing that colour from standard pigments.
Where are you located?  I suggest Googling your local paint suppliers and going to talk to them.  If they're anythng like mine it's best to do some background reading before you ask questions though.  It'll be quicker to get through to them what you want if you 'speak their language'.  That's what I found, anyway.

Edit - OK, Newmarket in Suffolk.  Should have looked before posting.

[BSA_54A10]

You have a good mask. Use 2K SS Satin black (SS - Single Stage means you won't need a clearcoat). IMV satin looks more authentic than gloss.
Then for the colour parts use basecoat and 2K clearcoat. 2K is harder quicker and is more impervious to chemicals, petrol etc.
Work in a covered outside area on a still warm day. The amount you're blowing (it ain't a car) is not enough to worry the neighbours.
I've been doing bikes and guitars for many years like this.

For bikes ( and mowers ) I use a HVLP ( high Volume Low Pressure ) Touch up gun.
They are gravity fed with a 4oz paint container on top of the gun.
The maximum fan on them is about 2" wide which is perfect for motorcycles.
4oz will do a tank and 2 side covers or 2 deeply valanced guards inside & out

[Slymo]

Ive had a bit of experience with 2 pack clear coats and coloured base coats and there is one point I would emphasize.  If you are going to paint in open conditions without an oven (heated spray booth) ensure that you hardener for the clear is suitable for low temperature catalizing. I used a 20-30 degree one on one project and whilst the finish was fine it had no resistance to modern fuel. I repainted with a 10-20 degree hardener and the result was much better.

[Joolstacho]

That's interesting that the chemistry didn't work.
I do take the precaution of pre-warming parts and paint before spraying, and I post-cure painted parts in my 'hot-box' (like a big insulated wardrobe) at around 40 - 50c
I use standard Auto 2k. Never had any problems (once I learned to spray that is!)