Poly, 2 coats of Shellac, then more poly???

[joe]

I was recently given about 150 sq feet of pre-finished oak engineered plank flooring(veneered) in a natural clear finish. It would match my 100 year old floors perfectly if it had a bit of an orange tint to it. Would it be possible to put two coats of orange shellac on top of the current finish, I assume it's poly, and then top it with two coats of poly?? I tried some shellac on top of the current finish today and it goes on fine, just wondering about the long term.

Thanks

[Anthony Diodati]

[David F. Eisan]

Hello there,

It will not work. Buy some Mixwax tinted poly (PolyShades I think is the name) and wipe that on.

David.

[joe]

Can you explain why it won't work? I tried scratching the test piece and it seemed to be pretty tough.

Thanks

[Silvan]

If you mix poly and shellac on the same piece, Larry Jacques will yell at you and call you a sinner. What more reason do you need?

[B a r r y B u r k e J r .]

Why not simply tint the poly?

Barry

[David F. Eisan]

Hello there,

Poly does not stick to anything, not even itself. That is why you need to "scratch-up" between each coat of poly with 220g paper, that way the next coat of poly has something to "bite" into. If you have ever recoated poly without a few swipes of 220 between coats, it will sometimes "delaminate" and peal off. Shellac (like lacquer) on the other hand just melts into itself, no matter how many coats you put on, it is really only one coat. But that is not the reason why it won't work, the poly is just to slick for the shellac to adhere to.

Go with the tinted Minwax Polyshades.

Thanks,

David.

Every neighbourhood has one, in mine, I'm him.

Remove the "splinter" from my email address to email me.

Newbies, please read this newsgroups FAQ.

rec.ww FAQ

FAQ

[Baron]

Overcoating an existing finish is always risky. There is always the chance for delamination. Here's something that might work though:

1. Clean the existing finish really well with something like dilute Murphy's Oil soap to get all the dirt and grease off.

1. Sand with something fine like 320. This will help to provide a"tooth'" for the overcoat layers. Do not use stearated paper.

2. Wipe down with naphtha or mineral spirits to remove the dust and any remaining grease.

1. Spray, do not brush, a dust coat of dewaxed shellac. Zinnser now makes Seal Coat which is a dewaxed shellac. Brushing might stir up any remaining oils and other contaminants to the surface which would undo all your hard work.

2. Spray a finish coat of dewaxed shellac. I like the idea of using colored shellac for steps 4 and 5 as I prefer to build up the color in sealed layers. This tends to give the wood a stained glass appearance as opposed to putting all the color in the top coats. Polyshades tends to have enough pigment and possibly dyes that the grain can be obscured pretty quickly. The top coats will also provide a little protection to the color if the top gets scratched.

1. Lightly scuff sand the shellac finish coat. Again, this is to provide a "tooth" for the finish coats.

2. Apply the top coats. Spraying is preferred but brushing can be done if you are putting polyurethane or varnish on top of the shellac. Don't forget to scuff sand between dried coats of polyurethane or varnish. I've never had much success with applying a second coat within the window suggested by the manufacturers.

Assuming you do not have a spray gun, your major equipment issue might be the sprayer. Using things like a Preval or Crown Spra-Tool could get expensive with 150 board feet. A Critter gun is the next step up but you will need a compressor or a truck inner tube to provide an air source. On the other hand, this might be a good excuse for you to get an HVLP spray gun if you don't already have one.

Good Luck!

To contact directly, remove both NGs.