Clearcoat Raw Steel Options?

Looking to clearcoat a brand new steel frame that's never had any paint on it. Anyone had much success with any of the following options?:

1. Clear powdercoat
   
2. Wet spray paint - acrylic or 1k (e.g. Spray.Bike transparent clear)
   
3. Everbrite brush-on clear coat
   
4. Protectaclear brush-on clear coat
   
5. POR-15
   

7 Attachments

1. Yes. Not great. It was very brittle and cracked off in a sugary kind of way. If that makes sense. Might have been the powdercoater I used, they were cheap. Brompton do clear powder I beleive and it seems to last pretty well.
   
2. Wet spray lacquer yes. I've tried quite a few. Halfords Heavy Duty PU lacquer seems the best but the spray caps and the pipe coming out the cans clog up so expect that to happen before you use the full can. I beleive you can get clear lacquers with an etching ingredient but they might be more like 2k cans or for running through a gun.
   3 - 5. Nope.
   
   

The clear powder coat from armourtex I had in my old Viking lasted well for the few years I had it, never seemed to be any problems or signs of problems, so if it's done well it should work. I don't have the frame any more mind so no idea if it's still ok after a decade +

Thanks, the Brompton clear powdercoat looks great in the flesh and seems to be a robust finish. If going the powdercoat route, I'm thinking it's worth getting it done right first time and paying extra for a premium quality powdercoater who understands bike frames.

Wet spray wise, I had a look at the Halfords Heavy Duty PU lacquer. The reviews are mixed, some excellent, others with complaints. If going the wet spray route, I'd actually prefer a brand that is more eco-friendly and less harsh chemicals, maybe even a plant-based clear spray lacquer if it exists?!

Has anyone ever hand-clearcoated a frame before? E.g. a tin of liquid clear lacquer and apply it with fine artist's paintbrushes.

Sounds like an interesting bike, curious how the clear powdercoat looked on your old Viking. Have you got any pics of it?

Halfords Heavy Duty PU Lacquer, as suggested by @M_V:
https://www.halfords.com/motoring/paints-and-body-repair/specialist-and-decorative-paints/halfords-heavy-duty-pu-lacquer-500ml-204581.html

1 Attachment

Pics for inspiration!

3 Attachments

done this several times with number 2

it works well at first, but you'll eventually get some oxidation... if you're okay with varying degrees of patina, then it will satisfy you well enough. After some time, I used to just respray the bike with the clear coat without taking it apart. it was somewhat of a rat-beater and the clear spray never showed up on the parts in a way that bothered me.

doing it on a warm, low humidity day is critical initially.

Here's a framebuilder which uses clear coat.

https://yasujirobike.com/product_detail.php?sn=12

Used to be real frowned upon among the framebuilding fraternity to just clear coat a frame.

I personally think powdercoat is a far worse sin.

No anti corrosive properties about (most) powdercoat and at least with clear you can see what’s happening to the metal.

I asked Dave Yates about it on his framebuilding course and he wasn't keen. Can't remember his reason.

seems to be a robust finish.

It's not, and many are swapped on warranty. My own frame is one of those that was saved from the skip, and the rust on the BB shell is not negligible.

No anti corrosive properties (generally the anti corrosive ingredient would be in the primer) and not impermeable by moisture.

I've emailed Yasujiro to ask if their clear coat gives as much rust protection as paint. Not really expecting a reply.

Been lurking these threads for a bit, haven't seen anything posted about this stuff - 'Jenolite rust shield'
https://amzn.eu/d/hjskLMn

It claims to 'Leaves an impermeable barrier against moisture and oxygen' and be 'Perfect for preserving rusted patina but preventing further rust'

I'm not entirely convinced that it will be hugely better than other people's experiences rattle canning lacquer over raw steel, but I've never found a product stating all this and seems ideal on paper.. (and curiosity got the better of me)
Hoping it has some sort of etching component as mentioned by @M_V

Will be using it on a rat commuter raw/rust steel charge plug project this week so will report back at some point

Update - this stuff didn't work.. hah

Lacquering (or 'clear coat' if you prefer) on raw steel is a bad idea.

As I've mentioned here in the past, when I worked in the trade we would refuse to do this because, when we'd done it in the past the customers usually came back complaining that the job was going rusty under the lacquer. We had tried our best to make it work and we couldn't do it - I don't think it can be done satisfactorily.

However, if you really must do it I suggest you use some sort of phosphoric acid pretreatment:

https://en.wikipedia.org/wiki/Phosphate_conversion_coating

This may colour the steel slightly, but it should give a key to the lacquer and some protection against rust.

If you look at old frames from the 1950s which haven't been resprayed, you will sometimes find a sticker stating that the frame has been 'Bonderized'. This is a phosphating process.

Have you frame phosphate dipped and lacquered.

Aurum finishing for about £120 ish