Correcting an Un-Catalyzed CV Coat

Thoughts on recovering from an "oops" ó forgetting to add catalyst to a batch of conversion varnish. March 9, 2010

I think I may have sprayed about one gallon of conversion varnish without catalyzation. I have about 15 drawerboxes, three full height end-panels and some sticks of flat millwork that all have one seal coat. What are my options? Does conversion varnish eventually cure without catalyst?

Forum Responses
(Finishing Forum)
From contributor B:
Someday it will cure. But not to the same degree as if you had used the catalyst to "lighten it up". Catalyze what material you have left (correct mixture, do not over catalyze) and take the remaining catalyst and mix with Toluene (one quart Toluene and your catalyst). Load this in a cup gun and turn the needle stop in until there is very little material coming out. You want a fine mist at low pressure so you don't have "bounce back" or overspray. Lightly apply this across your un-catalyzed work until all the material is used up. Cross your fingers. You should be able to finish the job but be warned, this is not a cure to your problem, only a quick-fix that gets the job done. Eventually, the acid will cross-link the resins, but not to the same degree as if you had used it correctly to begin with.

From contributor C:
I have been asked the same question three times in the last ten years by three other finishers/cabinetmakers. My advice was if you want peace of mind break out the lacquer thinner or stripper and get to work. Getting it off isnít rocket science, just time. Matching the original finish color to other parts that did not get the un-cat finish/stripped process is the bigger issue if staining or dying was part of the process. I hope I never do this, but I can see how easy it could be. Good luck and let us know what you did. I have heard about half dozen suggestions in my time but wouldnít try any. They all take time and material, just like the first time. Just start over.

From the original questioner:
As many of us know, it's not the second coat that wrinkles, it's the third. So on the drawers I was able to two coat them and they were fine. A little waxy feeling, but I'm hoping they'll eventually cure. On all the other stuff, I laid down two or three very light "dust" coats and then a final light/full coat, and they also turned out fine. There was some very fine wrinkling after the third coat, but that cured overnight and I was able to bury it under two light coats. Disaster averted - hopefully.