House of Kolor

[slapshot]

I bought a couple colors of choice from Coast Airbrushing & the House of color technical man which suggests using a reducer. My first question concerning the reducer is it just Lacquer thinner & do you need a special primmer? It seems that the manual pertains to a metal surface in the prep instructions. I use Tester's Aluminum plate buffing for priming & enamel paint for most of my projects. I especially like Boyd's paints but I'm running out of colors

[MikeMc]

I use lacquer thinner and it seems to work well, I prime with duplacolor primers.

I also use the prereduced colors from coast...

What is the difference between Reducer and Thinner ...????

[slapshot]

Yea I thought that lacquer thinner would work. I appreciate the confirmation. I will try out the reduced next time. All though I do like to control the paint viscosity.Thanks

Edited November 19, 2010 by slapshot

[Ddms]

I think those HOK colors are the same as the automotive urethanes I get at Finishmasters. FM also recommends reducer, and it turns out there's a good reason. I used regular lacquer thinner a few times, but then one time it caused the paint to curdle. It could be something to do with temp or humidity; I don't know. But now I always thin with a medium temp reducer called BASF UR-40, and save the lacquer thinner for clean-up.

[Ddms]

I use lacquer thinner and it seems to work well, I prime with duplacolor primers.

I also use the prereduced colors from coast...

What is the difference between Reducer and Thinner ...????

Umm... they smell different. So they aren't the same chemicals. And... urethanes should be thinned with reducer; lacquers should be thinned with lacquer thinner.

[Ddms]

Yea I thought that lacquer thinner would work. I appreciate the confirmation. I will try out the reduced next time. All though I do like to control the paint viscosity.Thanks

You'll be able to control the viscosity. Reducer thins the paint just like lacquer thinner.

[MikeMc]

Umm... they smell different. So they aren't the same chemicals. And... urethanes should be thinned with reducer; lacquers should be thinned with lacquer thinner.

OK but what is the diff?? I hear about both, yet no one seems to know what, when, where, why???

[Ddms]

OK but what is the diff?? I hear about both, yet no one seems to know what, when, where, why??? :D

Obviously, they are different chemicals, and only a chemist could give you a complete answer.

I did find a couple of good answers. One was on, believe it or not, http://www.mytractorforum.com/showthread.php?t=107680, "The Friendliest Tractor Forum and the Best Place for Tractor Information." It's from Mark77, one of the MyTractorForum moderators. Mark wrote:

Welcome to MTF Parkerco!

The paint manufacturers and related chemical industries sure make it complicated, don't they? And I believe they do it intentionally just to discourage anyone from venturing in to the trade without hundreds of hours of training. Thinners and reducers are different at the chemical core. Both solvents are designed to lighten the heavy viscosity of the raw paint you purchase in the can. The ratios (of thinner or reducer) are predetermined and tested at the manufacturers labs under controlled temperatures. Their findings are printed and provided either on the relative chemical cans or with supplemental "Product Sheets".

Thinners are more specific to nitrocellulose and acrylic lacquers, alkyd oil base and synthetic petroleum based paints. Petroleum based and Acrylic based chemicals do NOT intermix as they are incompatible (much like oil and water). The amount, or mixing ratios of thinners, typically up to 50% for final coating, control the spray amount and pattern through the spray gun. The amount used to thin the paint is directly related to texture, flow and drying times/temperatures. And most often discovered through trial and error, the finish achieved comes from the thinning, air pressure and gun distance performed by the painter.

Reducers act the same as thinners but the similarities end at thinning the paint into spray-able materials. Product branded reducers, normally manufactured to use exclusively for their specific brand line up, not only thin the paint, they are also available to control the paint flow by using temperature controlled chemistry for use in cold, warm and hot weather. They are designed to 'bind' at the molecular level and dilute the paint, hardener (nearly always used) and forcing it to flow, evaporate and cure all at the same rate. Today's reducers are used in base coat, clear coat, polyurethane, urethane, acrylic enamel and several primers and epoxy base/primer/top coatings. Extremely durable and very expensive...but far better with a much longer lifespan then oil based products.

Hope this helps a little,

Mark

Hey, those tractor jocks are pretty impressive!

Another good answer was on http://autobodystore.com/forum/showthread.php?2868-Enamel-reducer-or-Urethane-reducer. It's a forum for autobody pros. In answer to a question about enamel reducer (?) vs. urethane reducer, JimmyPtr, a senior member, writes this:

Use the urethane reducer. Think of a few things & it should make sense. Reducers are formulated to transfer a specific resin system (enamel, basecoat urethane, etc.) to the vehicle & then evaporate in a uniform way as to let the paint do its job. Enamel reducers are designed to transfer a thick (high build) coating to a surface & let that coating flow on its own. Urethane basecoats are about 1/2 as thick as enamels (hence sanding w/ 600 vs. 320).

If you use a fast evaporating enamel reducer in basecoat, the basecoat will dry too fast, resulting in bridging sand scratches & not allowing flakes & micas to seat properly. Then when you clearcoat, the clear will reflow & move the basecoat resulting in mottling & sand scratches.

Try this. Tomorrow at noon take 2 ounces (measure) of Enamel reducer & 2 ounces of urethane reducer. Pour them both at the same time on your driveway & watch which one evaporates quicker. Same thing happens w/ your mixed paint. Believe me- if high end body shops could save money by buying cheaper enamel reducers & still deliver quality jobs, they'd be doing it. With the amount of labor & material costs invested in a paint job, spending a few bucks more to produce quality finishes is well worth it. Also urethane basecoats are more chemically related to lacquers, not enamels. Hope this helps.

From my own experience, I know that thinning 1K PPG and Dupont urethanes with lacquer thinner is not a good idea, and I'm sure the same applies to HOK, Zero and Scalefinishes paints. Lacquer thinner seemed to work okay, then one day I realized that I was actually spraying curdled paint and didn't know it. I looked in my airbrush cup and the paint looked like a suspension - curdled milk - instead of a solution! Yikes. Even though the result was surprisingly good, I've used reducer ever since, and save the lacquer thinner for clean-up.

Edited November 22, 2010 by Ddms

[MikeMc]

Great answer Tom.....thanks :D