Gemini Coatings Pre-Cat Lacquer

Bill Arnold

1974
Staff member
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Location
Thomasville, GA
Are any of you familiar with this product?

Living in a small community is great, except sometimes. I'm about to run out of lacquer, so I went to the S-W, Ben Moore and Lowe's stores and found they don't stock any. I was steered to a local auto body paint shop that has a ton of it on the shelf.
 
Never used any. I only know nitrocellulous or acrylic lacquers.

What are the Pre-Cat and Post-Cat lacquers I keep hearing and reading about?

Aloha.

Tony,

Rather than trying to explain it myself, I copied the following from a Fine Woodworking article:

"Catalyzed lacquer
Like many of the finishing products now available to hobbyist woodworkers, the development of catalyzed lacquers was driven by market demand from the production furniture and cabinet industries. They wanted a product with the same look and ease of application afforded by nitrocellulose lacquer, but one that would also offer much better water, chemical, and abrasion resistance. The coatings industry put their chemists to work and responded by creating catalyzed lacquers, which are hybrid reactive finishes that cure chemically, not solely through the evaporation of solvents. Catalyzed lacquers contain some nitrocellulose resins, but the addition of urea resins makes these products much more durable. The chemical cure is initiated when an acid catalyst is added to the mixture.

If you want to buy a catalyzed lacquer, you will be faced with the choice between either the pre- or the post-catalyzed version. Both of them have a limited pot life, based on when the catalyst is added. The manufacturers of pre-catalyzed lacquer add the catalyst either at the factory, or in the store at the point of purchase. If you buy a post-catalyzed lacquer, you will have to purchase the catalyst separately, in another container, and do the mixing yourself. When mixing your own, there isn’t a lot of leeway for getting the proportions right; you have to be precise to end up with a finish that will cure properly.

Large, high-volume shops prefer the pre-catalyzed lacquers because their production cycles guarantee that they will use a predictable quantity over a given period of time. Buying the pre-catalyzed version saves them labor and time, and it eliminates the possibility of operator error in not mixing the correct proportions. Small shops usually prefer the post-catalyzed variety because they can mix what they need in smaller batches, avoiding the waste of having to discard the unused finish before it goes bad. Regarding the pot life, it will be affected by storage temperatures and the formulations vary among the manufacturers, so you’d be well advised to follow their instructions closely."
 
Thanks Bill!

I've always wondered that myself. Never used either, but at least like they say, 'Now I Know' :thumb:
 
I've used a lot of Gemni Coatings lacquer but not their precat. I do however use ML Campbell precat as our go to coating. It's great and it sucks a lot of $ out of my pocket each month. The Gemni products are not really up to the same quality as the ML Campbell however for general use its a good product. The precat has to be used within a specified timeframe so buying a large quantity is not a good idea if your project is small. We buy it in 5 gallon buckets and almost always use it before the expiration date. I think you either have 90 or 120 days after the catalyst is added.
 
Thank you Bill for finding that info for me. as Brent put it, "Now I know". I guess my projects, beinf usually so small, will get finished with Deft or Watco products, or similar. I may have some nitrocellulous and acrylic I can spray too, but it's older stuff, way before catalization.
 
FWIW, the plain NC lacquer has little variation between vendors - sort of like paint thinner isn't vendor dependent. But plain NC lacquer does not meet the wear and chemical resistance standards of the Kitchen Cabinet Manufacturers Assoc - KCMA.

As noted the catalyzed NC lacquer is better, and does meet KCMA standards after a cure period - as long as 30 days for full strength. The precat lacquer I have bought has a 1 year shelf life, but takes a long time to cure to full strength (you can still add coats in minutes, and have burn in for days). I believe the post cat can have much faster cure times, and indefinite shelf life.

I have largely switched to water based acrylic lacquer - specifically Target Coatings EM6000. In high tech finishes like this, the vendor still matters (as contrasted to classical finishes like NC lacquer and Shellac). The KCMA testing of EM6000 gives the same or slightly better results than the catalyzed NC lacquer. And it typically takes me 90 seconds for a complete clean of a spray gun.
 
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