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Will a precat lacquer "bond" somewhat over a uv polyester? And is a precat lacquer significantly harder than nitro (basic). And can it be "brush" applied?

MIkeslackkeymike39085.0370486111

[QUOTE=Colin S] As to it's durability, I have only had to refinish one top, and that was one I lent to my son! If applied correctly with enough pressure on the padding, then I believe it builds into a relatively hard and durable finish.

Colin[/QUOTE]

Colin said something I wholeheartedly believe because my grandfather pounded it into me. Other say I am nuts, but it is a belief I have and refuse to give up on. And that is; that firm quick stiffing-off or spiriting-off after every body session of French polishing after the first couple body sessions produce a tougher final film. Now Alen will likely jump up and spank me a bit over this, because solids can only be forced against each other and not compressed, and he is right. However my experience in French polishing and years of my grandfather's teaching showed me that in some way it does make the film more resilient.

Michael that's what our professional full time French polisher at the university thinks as well, he believes that the pressure is important in building a durable surface. He is a 60 year old guy that started his apprenticeship at 16 and has been doing it all his life. Although an experimental academic, I go with empirical experience evry time!

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

I used the cat urethane over the Taylor finish with success.

Try sanding back the area, then putting a sealcoat of shellac then your pre cat stuff. Ideally you would want a vinyl sealer in bewteen the coats but shellac will work. The product is designed for spraying. The dry time is really too quick for brushing. I suppose it could be done but I would spray. Unless you cover an entire area, expect witness lines.

This is the one issue I have with fast build FP systems. The fast build systems build beautiful finishes, but all the years of my grandfather teaching and all my years of French polishing shows me that the firmer (without causing dragging) the film is stiffed off the more resilient the final film. I am sure to some degree on the molecular level there is a reason this is true but not being a molecular engineer I can't argue with those that say that how you apply the film makes no difference in its hardness. All I can do is say I have painted on shellac and I have hand rubbed shellac and firmly hand rubbed yields a harder film in my shop

[QUOTE=Robbie O'Brien] Try sanding back the area, then putting a sealcoat of shellac then your pre cat stuff. Ideally you would want a vinyl sealer in bewteen the coats but shellac will work. The product is designed for spraying. The dry time is really too quick for brushing. I suppose it could be done but I would spray. Unless you cover an entire area, expect witness lines.[/QUOTE]

Any reason for shellac as opposed to nitro (before the pre cat lacquer?) Also, seems the pre-cat lacquer would have the advantage of some melt in with the base coat of lacquer over the shellac...

Mike

The reason for the shellac is adhesion between coats. Even if you put a coat of nitro and then the precat you will still have witness lines and possibly adhesion problems.