Conversion varnish crackle finish

How small-scale finishers can achieve big-manufacturer results. May 22, 2002

Go to a kitchen and bath retail outlet. Somewhere you will see a set of cabinets that has a crackle finish. The finish is conversion varnish. How is that done? What products and procedures are available to us regular finishers who are not connected with big factories? Big factories get custom-formulated materials to work with.

M. L. Campbell is coming out with a crackle for their conversion topcoats. ICA makes their SC Crackly (Screpolante) series special effects material. Since this is ICA, I am assuming that this product is for use with their polyester or polyurethane topcoats.

Star Finishing advises doing a crackle in conventional lacquer, nd then topcoating with conversion varnish. This hybrid approach sounds the easiest. Is this what the kitchen and bath cabinet companies are doing?

Forum Responses
From contributor D:
I have made numerous antique systems for some of my customers using both the Chemcraft and Valspar Wood Coatings crackle lacquers. Basically simple, the key is to spray the crackle lacquer as evenly as possible. The more you put on, the bigger the crack; the less you put on, the smaller. Let the crackle lacquer flash off, then put on your conversion varnish or NC. If you have never done this before, it is best to practice on scrap wood. Then practice some more, then some more, until you are comfortable enough to do the big job.

From contributor D:
On my way home last night I thought about my last response and realized I was backwards in telling you how the crackle lacquer is used. I'll put it in steps for you.

1. Prep substrate.
2. Lay down your basecoat/primer.
3. Allow basecoat to flash off or allow to dry longer, depending on how you want the crackle to look.

4. Spray on the crackle lacquer, remembering that the size of the crackle depends on the amount of crackle lacquer applied.
5. Allow to dry, then topcoat with NC or CV.

You can add a glaze on the crackle lacquer to give it an antique look. You can also color the basecoat and the crackle lacquer to give it different looks. I need to stress the importance of practicing on scrap wood.

From the original questioner:
Is the basecoat/primer lacquer based? Or can it be the basecoat or primer that you would normally use for a non-crackle conversion varnish finish?

From contributor D:
I have used it with a lacquer primer and with a NC basecoat. The crackle lacquer is mostly a solvent based (MEK) material that you put down on top of the basecoat. The crackle lacquer dries fast because of the solvent content and the crackles appear as the basecoat dries and shrinks. I imagine it can be used on CV basecoat/primer.