Any idea how many bikes a year get re-painted in the UK?

[Andy R]

In my opinion you have to go a long way to beat the durablity of Dupont Imron - any 1988 Kona Explosif, Cinder Cone or Lava Dome frame (the Paul Brodie painted ones) usually still look good even after 20 years.

If I was painting a frame today I'd be more than happy with the performance of Imron two pack polyurethane.

 

[PurpleFrog]

In my opinion you have to go a long way to beat the durablity of Dupont Imron - any 1988 Kona Explosif, Cinder Cone or Lava Dome frame (the Paul Brodie painted ones) usually still look good even after 20 years.

If I was painting a frame today I'd be more than happy with the performance of Imron two pack polyurethane.

I'd agree. The only paint by 88 Lava Dome has lost is to chain suck. You can still get paint with the Imron brand, but I don't know if it is as tough.

A lot of my concern is about rust on steel bikes, btw - water can travel through paint and cause rust beneath. The traditional way of handling with s was with a layer of zinc primer or galvanization, but this gets used up over time as it is sacrificed to the rust (that being how it works). If you're getting a powdercoat job on a steel bike ***do*** ask about primer!

More modern solutions include a layer of epoxy that acts as an impermeable barrier to water and oxygen, preventing the conditions for rust. Ideally you'd have a zinc primer underneath anyway, for scratches and because that impermeability might be 99.9% perfect, but not 100%. Then you'd have a UV resistance topcoat.

 

[PurpleFrog]

By professionals, I mean. At a reasonable rate - say £60-£100? There might well be something a LOT tougher than powdercoating and I'm trying to get an idea of the market size.

It's probably fairly easy to find tough(er) alternatives to powder coating - thisis one that comes to mind.
Bear in mind however that what might be ideal on a Land Rover chassis (and it is..) might not be so good on a bicycle frame. Some of these surface treatments add quite a lot of weight. Powder coating is also typically heavier than wet painting.
These things matter to some people - I don't necessarily mean myself here......

Good point!

 

[PurpleFrog]

early GT paintwork is very tough, still chips but is way tougher than Argos paint job.

Problem is, any magic tough coating is probably banned in some way due to its toxicity or environmental damage.

in the late '90's a lot of problems were caused when the automotive industry was forced over to water based paint. So many warranty issues with rust on panels!

The above is true, but those problems have now been solved. Otoh the new paints are toxic enough at the moment of application that you should really use an oxygen mask if you're spraying!

 

[PurpleFrog]

Nicely linking several of the comments people have made together...

..Imron, the paint Kona used to use, was an aerospace grade polyurethane paint. This stuff is considerably tougher even than epoxy 2 pack paints, which places like Argos Cycles in Bristol are now offering as a tougher option to their regular paints. Probably no one uses it on bikes any more because it is very, very nasty stuff!

http://www.bronkalla.com/upkeep/spray_imron.htm

Negative points include:

Extreme toxicity. Forced air respirator, skin and eye protection are a MUST. There are NO approved cartridge respirators - the isocyanates are odorless.

10-25% chance of developing chemical induced asthma which is permanent form exposure to the IsoCyanate hardeners

Relatively high "buy in cost" Need appropriate thinners, reducers, hardeners, forced air respirator, HVLP spray gun

Not for the casual user. These are designated as "professional use only" products. In some areas it may be hard to purchase as an amateur. Local dealer started to get worried with my questions. They are very concerned with safety and potential liability. Freely available published info is sketchy. It took a bit of digging to find the links listed. The Dupont information is in a sign-in only area of their web site.

I can vouch for the last part - the only way I found much out about this class of paints was by finding an aerospace engineer who was into bikes and getting him to talk to me.

Anyway, now I know the above there's no way I'll experiment on my 88 Lava Dome - it may have the best paint finish ever applied to any bike.