juvela

recently got a job back from the powder coater and the colour seems brighter, more saturated than the chip from which it was selected.

rather than put another opaque coat over the top am thinking about doing a tinted top coat. checked at a big building supply - hardware store and they could not help me. suggested a crafts supply store. again the response was "we no have."

does anyone know of an off-the-shelf line of rattle can colours to select from for this type of finish?

thank you for any suggestions.
---------------

n.b. - wrt product brands, am located in the u.s.

Flog00

Dupli-Color Metalcast? It is basically a candy.

Dupli-Color :: Metalcast

Tbone5

Not wanting to throw a wet blanket on this, but two thoughts to ponder. 1) Will a rattle can paint stick to a powder coated surface and 2) the rattle can paint is no way as durable as the powder coat. That being the case won't you end up with a bunch nicks in the spay paint finish leaving you with a mish mash of finishes?

juvela

yes, thank you for your thoughts. had considered this as well. am unhapppy with powdercoater for reasons beyond the colour so do not wish to return to their shop. trying to think about options...

juvela

WOW, help all the way from Milano!

thank you for this suggestion. certainly remember the "colour chrome" fad from the 1950's & early 1960's custom car scene. of course in cycles we have cromolux and cromovelato.

from their colour chart the "smoke anodised" might just do the trick for my needs on this project.

much appreciated.

CroMo Mike 

Although the Metalcast paints are sold as faux anodized finish (when sprayed over bare aluminum), I have used them as a candy color paint applied over a silver or gold metallic basecoat. Very close match to the candy red, blue, purple, and yellow of the 1970's. And very durable, too.

rgver

VHT make a product for tinting auto plastic light lenses, called Nite Shades. I have used it on chrome auto emblems for a black chrome effect too. It goes from subtle to dark depending on how many coats you use.

juvela

thank you everyone for these helpful ideas.

since whatever is used will be going over a powdercoat finish am wondering about the prep. would sanding to give the surface some tooth be a good course or can you see a downside to this?

Peugeotlover

You could telephone a different powder coat shop and ask about painting over powdercoat.
Best to get an experienced opinion.

crank_addict

I have no experience with powdercoat but first, if to paint over anything and for best adhesion should at a minimum scuff it. Don't skimp on the details around joints or lugs.

Anyways, back to experimenting 101. I'm looking at the scenario in a different way.

NOT using a rattle can but rather a higher quality touch-up spraygun. (An airbrush is too small for the task.)

I would color tint mix a clearcoat 2 part urethane and hit it. You want a faster set with an ideal hardener mix. Let it set up for say 30 minutes, scuff it and then another coat. The thing is, you probably already have a thick coat and any paint or other is going to build up more. But, by hitting it with multiple coats of clear, you'll get some depth.

(edit: Rattlecans- some are really tricky to work with and will spit vs. whatever piddly atomization they can put out. On a bike with all the tubes, there's compound surfaces plus potential overspray to close proximity tubes. If anything, have a dust shield ready (8 x 11 in. piece of cardboard), a better brand name paint with improved plastic nozzle and use a handle grip attachment. I'm sure others can pipe in but regardless, IMHO I wouldn't go this route.)

due ruote 

I have no real experience, but was told by a PC guy that because it's so stable, it's actually a good base for overpainting.

Please report back - we are all learners.

repechage

There is one bike painter that I was told used powder coat as a primer sealer… the client dropped in just to check on the progress… he was not happy and pulled the job. He thought he was paying for spray application throughout.
So, it can be used as such, not what I would do.

Powdercoat is a plastic. So, yes a scuff of some sort, (maybe even Scotchbrite pad, as less chance to sand through at the lug edges)
Then the overcoat. As to how well it will stick? roll of the dice to me.
Do think about total film thickness though.

It reads to me like the powder coat might already be a two stage application, color then clear. If so, that is pretty thick.

Lenton58 

Tough break, but I think it were me, I'd just try to get used to the what came back from the powder people. Once all the parts are on it, along with some bar-tape, the hue might not look so obviously wrong. I'd like to see a picture.

In a former life, I was a painter. My supplier was excellent, but there were times when paint had to be "adjusted", even though the mixing formula had been accurately applied. In addition to the paint-tech guys, there was a trained interior decorator on staff who was most brilliant at adjusting hue. She was more skilled than the actual "paint-mixers" because her training had been very much more advanced. And so sometimes I would wait until all the smocked paint-techs had gone home. Because she worked after business hours, I'd knock on the back door and she'd let me in and change the hue according to how I would describe what I needed.

The salient point is this: I forget the exact, technical terms, but the actual hue on the chip is specified by an angle at which light is reflected off the actual paint surface as tested by the manufacturer. The chip tries to translate this into something that is as close as possible. Pro-painters and amateurs alike use the same chips, but professionals get more used to translating the chip to what they imagine it will look like on the surface they intend to paint. Now, this is going back years, and computer technology might be changing how people are able to see what they are buying — I'm too far away from this stuff now to know what happens at the paint store.

Anyway, you cannot be 100% sure what a hue will look like until you get it on the wall and in the light that is reflected off it. That was why we often bought a pail of paint first instead of an 18 Litre drum — to see what it looked like on the site. Inevitably there were times when the paint had to go back to the supplier and changed by readjusting the formula. (And, by-the-way, there can be a limit to just how much you can alter a hue before you screw up the paint.) Just how well you and the supplier communicate will determine the accuracy of the final result.

In recent months, I ordered some rattle-can paint to cover some damage on my wife's Honda. I absolutely cannot tell the new paint from the old — by hue that is. Why? Because the formula is an exactly known constant, and whatever panel it is on, both the old and new are reflecting light at the same angle.

A lot of people will be thinking that one of the easiest paints to match is black. It isn't. In fact it can be a nightmare. A partner and I once looked at auto-paint chips for a black we did not have a code for. After pages and pages of different blacks we were totally befuddled. We ended up faking a repair on a black Lincoln.

Whatever you may try, things could either work out better for you — or worse! And of course, as pointed out above, adhesion and the strength of the new coating are other issues.

And some people think painting is easy!

repechage

Lenton58, knowing color thoery really comes in handy. From a former life and occupation, I have bulldozed myself into the auto paint supplier's color mixing room, "show me your toners..." . One thing to note is that when you start mixing colors, chroma (brightness , intensity) falls off pretty fast. If a color is bright, the closer you are to begin with the better.


And indeed, black is as big a challenge as white. There are bunches of ways to push black, often done with red, yellow on more modern stuff. Sometimes blue and red. And not always a pigmented toner, but translucent. A color I would hate to shoot would be one of the new black metallics, or Micas. Heaven help the guy who is asked to spot blend the hue flopping metallics that Ford used on one of the special Mustangs a few years ago, $400. A quart at the time.

Lenton58 

I quite agree. I did some work for hi-end designer/decorators as a sub-contractor. Some of the colours were very bright, or intensely dark but retaining some life in them. Sometimes clients would freeze up during the final consultations; the boldness scared the hell out of them. The designers were high flyers and getting paid a lot of money, so they usually got their way as long as they had some reassurance from me that I could supply the paint. In those cases, I had to reassure the designer that I could get the colour as well as the hue, but it often meant shopping around for a manufacturer that made the base paint. Only the most expensive brands could supply a base that would accept the toner without the desired hue growing muddy. I had the help of good paint-techs and a supplier who would obtain special orders. Sometimes I would consult an artist who is a close friend. She was trained at Cal Arts when it was still Chouinard (spelling?) She knew colour theory like some people know "The Lord's Prayer".

I have a 21 year Yamaha SRX-4 sports single motorcycle — a very rare machine in North America. I have already decided that should I ever have to repaint the tank and Kevlar parts, I'd just not even try to get a match for the metallic black — unless the factory still retains the original paint, which is not very likely.

Reproducing the exact hue of a great classic bike could be a challenge in some cases.

juvela

thank you all for your thoughtful replies.

have a touch-up spraygun as suggested by crank-addict but no air to drive it. used it to paint scores of framesets back in the seventies and eighties.

should have mentioned that my item is not a cycle frame but rather the body panels for a kitchen appliance. doubt it matters from a finishing standpoint.

will post an update after having a go...

thank you again.