During my career in furniture restoration, both "Pre and Post" catalyzed finishes were introduced to the small user. "Pre" catalyzed meant the catalyst was added to lacquer by the manufacturer. "Post" catalyzed meant having the end user add the catalyst to the urethane just before applying the finish.

Pre-catalyzed lacquer finishes do not have a critical timeframe to use the product so it has a very long pot life, much like regular nitrocellulose lacquer.

Post-catalyzed urethane type finishes have to be used within the narrow window of time required, otherwise the finish will start to catalyze which, once started, can't be reversed. This will cause great havoc on any equipment being used because it will start to harden no matter what and whatever is in the gun is going to stay there. Once this happens the equipment is ruined and any finish already on the project virtually can't be stripped off. It has to be sanded off which is a very tricky process and can ruin the project altogether.

It is for these and many more reasons that became apparent after using these types of finishes that I stopped offering them to my clients. These products were designed to be used in closed finishing systems that are dust free and fully automated.

Since I mostly worked on antiques and family heirlooms I can't ever recall any of the projects that I worked on as having these types of finishes on them, with the exception of a couple of do it yourselfers. It didn't take long for me come to the conclusion that I needed to go back to "keeping it simple" and only offer my clientele good ol' nitrocellulose lacquer, shellac and plain varnish. If they wanted something tougher than an oil based varnish, which, by the way, is a very durable finish, I would send them elsewhere.

Alan can be reached directly via email c/o Alan Noel Furniture Refinishing at anoelfurniturere@bellsouth.net .

Visiting Atlanta? Attend one of Alan's upcoming highly informative Highland Woodworking wood finishing seminars:

March 6, 2019  Finishing the Finish
March 30, 2019  Finishing 101
April 3, 2019  French Polish Workshop
April 27, 2019  Finishing 101