Does anyone know how it works if you use dewaxed shellac, like the Zinnser or Parks Pro dewaxed shellacs, as the sealer under a hiqh quality, cross-linking waterborne poly like Traffic, Mega, Emulsion or Street Shoe? I want the speed, low odor, and durability of one of these waterborne finishes, but I also want a nice amber color from the seal coat (without using stain) on my new American Cherry 3/4" hardwood. The Bona Kemi folks recommended their DriFast sealer, but I have the impression that dewaxed shellac will give me greater tone.

Anyone know if that's true, and if it is, if it's feasible to use dewaxed shellac in this case? With the waterborne polys I can buy at Home Despot (Parks Pro and Minwax Professional version), they suggest putting down the dewaxed shellac and then "hot" coating it within about 45-90 minutes. Then you nub down the grain after the first coat of waterbase. I've heard this works well. I'd like to try that with one of the higher quality polys mentioned above.

I am a DIYer about to do my first floor finishing job, on my own home. I can buy the Bona Kemi and Basic Coatings products (also Dura Seal) from Trinity Hardwoods here in Austin, Texas. I am leaning toward Mega or Emulsion because they may be easier to use, but the floor will be in a kitchen/dining area, so if you think I would be better off with Traffic, and it's not too hard to apply, let me know. I've put waterbase poly on an acid-stained concrete floor before with good results, and I've finished a lot of furniture, so I am naively optimistic I can handle this.

Appreciate any and all advice - this will be my first wood floor finishing experience.

Yes, the de-waxed shellac works well under any polyurethane, either oil-based or water based. The color would be very close or similar to using Bona's DriFast sealer. Bona's sealer, IMO, is easier and less flammable. Plus I think it's a little less money. I use it all the time. The difference is that with the shellac, you can go over it without buffing (hot coating) whereas you should buff out the Bona DriFast sealer. Both Mega and Emulsion are easy finishes to apply for water based finishes but are not terribly durable. Traffic is much more durable but is for pros only as it uses a catalyst. The distributor may not sell it to you. IMO, I'd use an oil-based poly instead of Emulsion or Mega. Less money, easier to work with, more durable. The only reason to go with DriFast or de-waxed shellac is to achieve that richer color of a solvent finish when planning on using a clear water-based finish. If using straight oil-based poly, then forget the sealers and just apply three to four coats of oil-based poly. It will scratch but all finishes do, everyone of them.

Gary, thanks for the suggestions. A part of the problem I should have mentioned is that my wife and I and our two kids are living in the home while we do this work. We have the room with the new hardwoods partitioned off with plastic, but I am not sure we can handle the odor of oil-based poly drying and we do not have any place to live while it dries, short of camping in the back yard! Were it not for that, I would try an oil-based poly, for the ease of use factor. But as it is I want to go with waterborne for the speed and low odor. The local distributor will sell me the Traffic, so in the end I just need to decide if I can apply it or need to use an easier product.

Both the sealers you mentioned have fairly strong odors. Keep that in mind as well.

Use the dewaxed shellac and apply the Traffic for an odor free night at home.

As Gary said, the DriFast and the dewaxed shellac look very much the same but you only have to smell the shellac for a very short time.

Thanks, I will try it in about a week, probably the Traffic over dewaxed shellac, and let you know how it works out.

How did your plans for Traffic over shellac go? I'm looking at Traffic over Waterlox and, like you, I'm an "advanced beginner." I'd like to know how the application of Traffic went from another DIYer's perspective.

Wally, I ended up going for Mega over shellac, using Parks' Universal Sealer. I am having problems right at stage one, however, b/c the sealer was a lot harder to apply than I'd bargained for and I got a bunch of lap marks. (Didn't help that I stepped in the paint tray either.) I am posting a new help request to fix my lap marks, and then will get back to let you know how the Mega works.

I can now give a final report on using Mega over Parks' Universal Sealer (a 2lb cut shellac) on 600 s.f. of American Cherry: It worked great and looks fantastic. The shellac warmed up the cherry quite a lot. Initially, after just the shellac coat, I was totally bummed and thought the floor looked too yellow. (Amber was the only Universal Sealer product at our Home Despots.) I had just seen the total beauty of the natural cherry when washed with mineral spirits, like a Thomas Moser table, and this shellac-look seemed too yellow, not helped by the blotchy appearance typical of a seal coat. Once the Mega went on there, however, the look became rich and very close to the mineral spirits tone -- very Thomas Moser, which was my goal. The floor has a wonderful natural cherry color, without stain, meaning it will alter naturally with the years as the cherry slowly darkens. The satin Mega final coat was a major improvement over the gloss initial coats, cutting down the glare and visible, uh, imperfections in our application style, and giving the floor a rich luster.

For anyone else attempting this as a DIYer like me, here's what we did.

1. After sanding with a rented U-Sand, filled minor gaps between boards.

Had there been a lot of cracks I'd have used trowelable filler from Woodwise, natural cherry color, doing the whole floor at once and sanding it off, but since there were not too many, we used the Woodwise wood putty and did them individually. This was very hard, detail intensive work but completely worth it. FYI the Parks trowelable filler available at big boxes did not look good - could not color match it, out of the box or with tints. The Woodwise looks great and was highly workable. We got it wet and sorta semi-troweled it with our fingers, then wiped off the excess with wet shop rags and sanded with our final grit (150) to get off any residue. Had to mark each spot worked on with painter's tape to see where they were.

2. Applied just over 1 gallon of Parks' sealer to the 600 s.f. of flooring.

Here I created the lap mark problem that started this thread. I used a Padco 10" floor applicator, which was quite easy to use, except I didn't realize how visible the lap marks would be up against a few of the walls. With some tips I was able to work out the lap marks from my initial coat of shellac -- it was hard work, but shellac is so user-friendly, it was not hard to do it well (using no sanding, just a combo of denatured alcohol to work down the lap marks and then new shellac, diluted to 1lb cut, so build an even coat, feathered to the existing).

3. Made repairs within 24 hours and hot coated the shellac without abrading it.

This is recommended by Parks. You can hot coat it in 45 minutes, and I was told you have up to 48 hours, though that may be pushing your luck. Unlike other shellacs, the sealer is not supposed to sand well, even after 48 hours, perhaps due to some propietary stuff they add, so they recommend hot coating.

We used a Padco 10" applicator for the sides and corners, and an 18" Bona Kemi pad for the main thoroughfares. I have to say it was pretty easy to get the knack for using both applicators, and I loved the 18" pad, though learning to pour the right amount of finish was tough.

The first coat of Mega was gloss. My wife and I applied about 10-15 percent more than recommended, by accident not by design, but we figured we coulda done worse.

4. Spot sanded and lightly abraded first coat of Mega.

This coat came out well but had more hairs and dust nibs than expected. We sanded individual spots. I did not have the Bona Kemi maroon pads or a buffer for between coats, so instead we did a light pole sand using 320 grit regular paper. The Bona Kemi instructions say you don't have to abrade after coat 1, but b/c you do not abrade the first coat of Universal Sealer, the Parks' instructions recommend you abrade after the first coat of finish. We did, and it was very easy.

5. Applied an extremely clean second coat of Mega gloss.

I am skipping all the vacuuming, which we did endlessly throughout this process. I also tacked with mineral spirits before the sealer coat, and tacked with lightly water-damp shop rags before each Mega coat.

6. Corrected more problems we created with second coat.

I created two more problems with this coat. First, I left a puddle near the doorway out of the two rooms being finished (it was hard for me to gauge volume as I completed each room -- i.e., I used way too much finish at the end). Being in the doorway from another room, the puddle was highly visible in the raking light. Called Bona Kemi and they advised me to sand it out with 100 or 150 grit, which I did (in that sequence) with my random orbital sander, followed by hand sanding with 220 and 320. I cleaned it up and applied a light coat of the Universal Sealer to cover areas where I may have gotten down through the sealer coat during my repair job (a 3" spot was visible, but other streaks were hard to spot until I applied the sealer). We let this dry 1 hour.

My second problem was where a 5-foot threshold piece, a nice bullnose on a step down betwen rooms, is perpendicular to the regular floorboards. I had cross-grain lap marks on the threshold from pulling out the end of the flooring. Sanded these down with the 100-150 seguence very lightly using the random orbital sander, then finish sanded to 320, and then after clean-up applied tape to the threshold, so I would not hit it again in the final coat.

7. Pole sanded the whole floor very lightly again with the 320 grit sandpaper (except for the newly re-sealed section).

8. Applied the final coat of Mega satin.

I did the threshold at the spot between floors, pulling off the tape and using my padco applicator to go with the grain this time.

I may apply extra satin over the repaired puddle, but so far it looks seamless with the rest.

The whole thing looks beautiful. Can't say I want to do it again anytime soon, but we are very pleased. Now let's see how three coats of Mega holds up - this is a kitchen / dining area. I did not feel comfortable using Traffic for my first home job, nor did I want to drop $400 on finish, and I am hoping three coats of Mega should do the trick for a good while.

I hope you did not use Zinsser's Bulls Eye Amber Shellac. That is not the Dewaxed Shellac. Zinsser Sealcoat or Parks Universal Sealer are dewaxed.

This is the wrong one.
http://www.zinsser.com/product_detail.asp?ProductID=31

No - if you see the rest of the post, I used Parks' Universal Sealer, which is dewaxed, and which worked out great. It's designed for use under water base. I was just mentioning for the unitiated like myself that the seal coat itself doesn't look so great until you get the actual finish on top of it.

Yes I saw #2 where you mentioned you used Parks Universal Sealer but the first part of your post made me think of what happened to a carpenter I know that sanded his own floors and went to Lowes to get the same sealer but they sell Zinsser Sealcoat so the confusion began.

He asked for the Parks Universal Sealer and said it is shellac. The girl asked why he wanted to put shellac on his floor and he said he wanted to amber the floor before putting on his water-based topcoats. She said we don’t have Parks Universal Sealer but we do have amber shellac. Well he put it on his floor then called me and said the sealer made his floor too yellow. I went to his house and saw the can of amber shellac and helped him sand it off.

Your post is very clear and you did your homework on this job but after what happened to this guy I am a bit paranoid.

Thanks for the review of your process. I'm putting Am Cherry down on about 2000 sq ft of our new home and am doing my testing on a small powder room and wet bar that total about 100 sq ft. I'll work the bugs out and then tackle the remaining 1900 sq ft. I'm using Waterlox under Bona Traffic. Since the test rooms are small, I've done all sanding with a 6" random orbit sander and now have the two coats of Waterlox down. It looks good so far, but I can see some sanding necessary before I hit it with the poly tomorrow. Your saga gives me confidence that my wife and I can handle this job. Thanks!