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Discussion Starter · #1 ·
What is the best topcoat that I should use over a waterbased dye? I understand your supposed to seal it with shellac first but should I be using afterwards? Lacquer, varnish, poly or is the shellac enough?
 

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Discussion Starter · #3 ·
It is for a small table top..I just got done with a large picture frame and used dye and used a waterbased lacquer in an aerosol can for the top coat. I did three coats sanding at 320 in between and then on the final coat went from 320 to 600 to 1200 using purrifin oil but it seemed to have an orange peel look to it. I would like to use something I could apply by wiping on if that is possible because my spraying skills are not very good yet. I would like to achieve a semi gloss finish with no orange peel.
 

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If I was going to wipe. I would put 2-3 coats of shellac on, no sand between but 400 after final has dried. Then I would do a 50/50 mix of good quality oil based poly and mineral spirits(5-6) coats of that or until I was happy sanding after 2nd and 4th with 400. And wait atleast 5 full days at 75-80 degrees before any buffing.
Also I would do a story board right along side the table top that would be finished in the same manor and use that as a guide rather than the top to test dryness.

You can also buy pre-mixed wipe on poly but I personally don't like it.
 

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tdoucette67 said:
What is the best topcoat that I should use over a waterbased dye? I understand your supposed to seal it with shellac first but should I be using afterwards? Lacquer, varnish, poly or is the shellac enough?
I don't know why this post hit me odd. I think it was the use of the word varnish in relationship to an alternative to poly. I don't know.

The parts of varnishes, or the items that make up different varnishes, are resin, solvent, and a dryer. There are different types of resins, solvents, and dryers.

Resin: this is the deciding element regarding what type of varnish it is, a natural varnish or synthetic varnish. Some of the most popular synthetic resins put into a varnish are: acrylic, polyurethane, and urethane. It is common to call the varnish by the type of resin in it; therefore, polyurethane is a type of varnish. Polyurethane is not a different finish than a varnish. It is a varnish. With that said, there are still different types of varnishes than polyurethane.

Natural varnish: the resin is typically rosin. The solvent is normally turpentine or mineral spirits. The dryer is normally linseed oil.

Oleoresinous varnish: the resin is either ester gum or rosin. The solvent is either turpentine or mineral spirits. The dryer is a synthetic drying oil or mixture of different synthetic oils.

Synthetic varnish: The resin can be acrylic, alkyd, epoxy, phenolic, polyurethane, or urethane. The solvent is a chemical reaction that can be a triad secret depending on manufacturing company. The dryer is either synthetic oils or emulsified oils. This could allow for a water clean up and sold as a water varnish even though there is oil in it. Powdered silica can be added to create a satin finish.

Okay I'm going to stop now, even before I get into shellac or enamel. They are a little different.

I hope this helps the terminology.

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What is the best topcoat that I should use over a waterbased dye? I understand your supposed to seal it with shellac first but should I be using afterwards? Lacquer, varnish, poly or is the shellac enough?
You don't have to use a barrier coat with a water based dye. As long as you let the water dry you can topcoat with the protective coating of your choice. Now having said that the protective coating needs to go with the color you are doing. Finishes such as nitrocellulose lacquer, varnish and oil based polyurethane yellow over time so are not the best choice for light colored woods. On light colored woods, a cab-acrylic lacquer or a water based polyurethane will work better as they won't yellow. Any finish will work fine on darker colors however some are more water resistant than others.
 

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It's now morning and I had some other thoughts. If you noticed that there is oil in most all of these different varnishes; however, they are not to be considered an oil varnish. There are oil varnishes, but that is a little different. The oil that is used in a varnish is normally heated and treated to help the drying process. I'm not a chemist so I don't know exactly what happens but I do know that there is a change that happens to the oil as it heats in combination with the other items in the varnish. After the varnish cool, additional oil is added without heat to make an oil varnish. The oil might had been individually heated like BLO but not with the other ingredients. Regarding BLO, as far as I can tell, it used to be boiled to help it harden but now chemicals are added instead of boiling it. So Boiled Linseed Oil is not boiled anymore. Well, I'm sure we could find a traditional company that might still boil it, but how would we ever know as consumers? That is part of the problem with varnishes, marketing. The companies want you to think that varnish is different from polyurethane. You will buy both. They want you to think that their finish is something special and they change the name or stretch the meaning of different items. There might be something very different and special about one of them or they might be almost exactly the same thing.

You have to read carefully. A boiled linseed oil finish might not be pure boiled linseed oil but just a finish that promises an end result that looks similar to BLO. There might not even be any linseed oil in it. The container should say pure BLO or buyer be ware. It might not be linseed at all.

It's the marketing that has confused customers to think that polyurethane and varnish are completely different when polyurethane is just one type of varnish. Trust the companies that they are telling you the truth but don't trust the companies because they might be deceiving you.

One of the confusing things is a water based polyurethane is not water based, there are oils in it with a lot of chemicals, however, in the process of making the polyurethane varnish they do so so it can be cleaned up by using water. If there was water in it, it would take forever for it to dry. It is just one of those marketing ploys to get you to buy something special and I guess it is special because they have helped in the clean up process.

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I just finished applying the last top coat on the kitchen cabinet doors yesterday. I used Trans Tint dye, diluted in water, and 3 coats of General Finishes EnduroVar. Nothing in between. The EnduroVar was sprayed on.


This is two of the doors, the panels book-matched. Mahogany rails & stiles, sapele panels.

I did a lot of reading, asked a lot of questions and read a lot of solutions. I opted for the WB dye/WB finish because of what I had learned, what the doors will have to endure, my skills and the my particular working environment. And then I crossed my fingers. The doors turned out better than I expected.

In the process of trying to find the right color formula and the best finish, I sprayed some lacquer directly over the WB dye. BAD IDEA! The sample piece turned an splotchy grey/black. Shellac was fine but dulled the grain pop. Varnish did pretty much the same thing. Samples are a beautiful thing!

Prior to this I had religiously used oil based stain, sanding sealer and varnish. All Pratt & Lambert and all on red oak. I had a few ventures into lacquer on bare wood for grain pop and it worked fine. But the wood was to be toned, I always used my old standard. With this venture into WB finishes, I feel like I came out of the stone age.
 

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Discussion Starter · #10 ·
The finish I want to apply is fairly dark I believe it is called vintage cherry from general finishes. It is a waterbased dye. I have no problem applying the dye I'm just confused about the topcoat finish, when I should sand and what grit. I'm trying to achieve a semi gloss look without any haziness. I don't know if its my spray technique with the lacquer or the fact that its an aerosol or if spraying lacquer over a WB dye is a bad idea like Julie said. Also I have an earlex spray station but I just felt wiping on a finish involved less skill since I am a very novice finisher.
 

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Steve I think he's looking to wipe. Shouldn't you use a barrier coat with that method?
No, a barrier coat is used to make a transition between two different products that are to some extent incompatable with each other or as a sealer. If for example the OP used linseed oil and then was going to put a water based polyurethane over the top then sealcoat would be a good barrier between the oil and the polyurethane which are incompatable with each other. Otherwise the linseed oil would have to thoroughly dry before using the poly over it. The sealcoat would accellerate the process as it would adhere to the linseed oil not fully cured and the poly would adhere to the sealcoat.

If the OP would had used a alcohol based stain and was going to topcoat with a water based poly then the sealcoat could be used to seal the wood so the water in the poly wouldn't raise the grain. The sealcoat wouldn't be needed for any other reason. Putting water based poly over water based stain doesn't matter. The grain is already raised when the stain was applied.
 

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The finish I want to apply is fairly dark I believe it is called vintage cherry from general finishes. It is a waterbased dye. I have no problem applying the dye I'm just confused about the topcoat finish, when I should sand and what grit. I'm trying to achieve a semi gloss look without any haziness. I don't know if its my spray technique with the lacquer or the fact that its an aerosol or if spraying lacquer over a WB dye is a bad idea like Julie said. Also I have an earlex spray station but I just felt wiping on a finish involved less skill since I am a very novice finisher.
When you use a water based dye, the only thing you need to do is let the water dry out of it. After the water is gone you can finish the wood as though it was never stained except you need to keep from sanding through the finish in between the coats sanding. Any clear coating is compatible with it. If you wish to keep the haziness out of the finish and use lacquer as a topcoat, use a minimum of sanding sealer and build your finish with a clear gloss lacquer. Then when you think you are ready for the finished coat use the semi-gloss. The flattening agents in the lacquer is what makes it hazzy. Don't go overboard making the finish really thick. About 3 mils thick is customary. 3 mils is about the thickness of a lawn and leaf trashbag.
 

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Hmm

I would be worried about the pulling the dye right off as soon as it get wet. if wiping or heavy spraying. A seal coat would stop that. It doesn't hurt.

http://www.homesteadfinishingproducts.com/pdf/TransTintTDS 6-2009ii.pdf
To tell you the truth I've only used one water based dye and it's been some time ago. The dye I used colored the wood as well as an alcohol based aniline dye. I don't think it wouldn't have lifted with a power washer. It was about 1987 and I believe it came from Star Chemical which is no longer a company. I don't currenty have a water based dye in my shop. Could you try it and let us know if the dye you use lifts easily and let us know. You're right, there is no reason sealcoat couldn't be used and would certainly seal the dye in.
 

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Discussion Starter · #16 ·
Thanks everyone for the suggestions. I'm going to try to spray the topcoat (waterbased polyacrylic) with my earlex and hope for better results. I think my problem was using an aerosol. Also I was under the impression to use a sealer with a dye so you don't lift the color off with the topcoat.
 

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I would be worried about the pulling the dye right off as soon as it get wet. if wiping or heavy spraying. A seal coat would stop that. It doesn't hurt.
If you spray, there's no problem with the dye lifting off. You should never heavy spray. If you're brushing on the top coat, the longer you wait between dying and brushing the top coat, the less dye will be lifted. Just don't brush it over and over again on the first top coat.

On average, it takes about 100 hours for dyes, stains and finishes to fully cure.
 
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