Why We Love Dewaxed Shellac
Elisha AlbretsenDewaxed shellac is a must-have in your finishing cabinet. It’s almost too good to be true. One of the biggest benefits of dewaxed shellac is that it’s compatible with ALL other finishes, from paint to polyurethane to lacquer, water-based or solvent base.
The product we’re using
The dewaxed shellac we both use is Zinsser Sealcoat. Although it’s called Sealcoat, look closely at the label and you see that it’s 100% dewaxed shellac.
Waxed vs. dewaxed
It’s imperative that you use the right product. Some shellac has wax in it. When you’re using shellac as an undercoat or sanding sealer or seal coat, intending to put another coat of finish over it, it must be dewaxed shellac. Top coats may not adhere to shellac with wax in it.
How we use dewaxed shellac
Here are some examples of spots where we find dewaxed shellac indispensable:
- Refinishing a project. If you don’t know what the existing finish is, start with a coat of dewaxed shellac. It’ll stick to any existing finish, and whatever you want to use as a topcoat will stick to the shellac.
- Under paint. Latex paint can raise the grain on wood. Put on a coat of dewaxed shellac before painting to eliminate that problem.
- Seal knots. Knots, especially in pine, can bleed through painted surfaces. Seal knots with dewaxed shellac before painting.
- Under water-based finish. Like paint, water-based clear coats will raise the grain. Do a seal coat of dewaxed shellac so the water-based finish never touches the wood. Shellac also adds a nice amber tone that water-based finish doesn’t have.
Experiment
Give dewaxed shellac a try. You can brush it on or spray it on. It’s always a good idea to experiment with new finishing techniques before trying those techniques on a project. There are lots of good ways to do quality finishing on your projects. Find one that works well for you.
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11 Responses to “Why We Love Dewaxed Shellac”
So in the time that you've been here Mm-hmm shooting video, we found we have a number of things in common. One of which is our love for dewaxed shellac. Yep. Which, as people who do a bunch of finishing, I think it's kinda natural. So we're gonna wax philosophically about dewaxed shellac.
So... You tell me what's your deal? What's the deal with dewaxed shellac? Sure, yeah. I'd always heard people talking about this thing called sanding sealer.
I didn't really know what it was, or seal coat, this brand likes to call it. But, basically, what it is, it's dewaxed shellac, and it's a really thin solution, but you can put it over your surface, and then it won't raise the grain when you come back with whatever type of finish you want, whether it's water-based, oil-based, paint, you name it. So, it's like the wonder drug that works wonders to steal that line Yeah. from that old commercial if you're not aware. And as it turns out, we were just saying there's even, I never knew this was written on the can, but it's written on the can right there.
This finish works under all finishes, and, again, if you're not aware, the surprise for that can be like, if you try to put lacquer over polyurethane, Mm-hmm. you're probably gonna have a problem, because they won't adhere. So there are a lot of finishes that don't play nice together. Yep. It's especially a good idea if you don't know what the existing finish is- Like on a- Right.
So you've done a lot of refinishing. Right, right. You can always add an extra little safety layer of shellac and then you can follow-up with whatever modern finish you want. I'm gonna brush while you're talking, so you keep going. What else?
Okay. Hey, you wanna borrow my gloves? Yep. So, nowadays, a lot of people like to use- Oh, I don't need that. Nevermind, sorry.
Keep going. Nowadays, people really like water-based finishes. They're lower in VOCs, they're really accessible. So people are leaning more towards water-based finishes. The problem is, with that, if you have a raw board and you put a water-based finish on it, what's gonna happen?
Gonna raise the grain! Yep. It's gonna feel rough and it's gonna have lots of little fuzzies on it, especially, certain types of water are bad with that. So, what I do, because I don't wanna have to sand everything another time, I put a little layer of dewaxed shellac, let it dry. Dries very, very quickly.
And then I can follow up with my water-based finish and it won't raise the grain. And I'm in a similar boat, but part of my deal is that I don't like the way that water-based finishes are so clear. Mm-hmm. There's really zero color to 'em at all. Yep.
And you can see from what I've got going here, there is an amber tone to the dewaxed shellac. So I do the same thing. I put dewaxed shellac on first, then I come back and I put it with my water base. And I like that it imparts a little bit of that amber to the wood. Mm-hmm.
The other place I've used it a lot is even on a paint grade project. If I'm working with pine and I'm gonna paint over the top of that and there's a knot in the pine. Mm-hmm. If you don't take a step, what can happen is, over time, sap from the knot can start leeching Mm-hmm. through the paint.
And you've probably seen this, you know, if you've looked at other people's work, pre-sealing that with dewaxed shellac before you paint will prevent that knot from being able to bleed through the pine. And then, again, with the... We've done other videos on good material choices Right. and bad material choices for paint grade projects. Pine's not a great material for paint grade unless you pre-seal it Sure.
for all the same reasons. Then the paint can't get to the pine and raise the grain, and it's sealing in the resins from the knot so they don't telegraph through later. It's also a great way to save product, because it helps seal the wood. And so if you have an especially porous material that you're working with, it can pull in your paint or your finish unevenly, get blotchiness. So, putting a layer of sanding sealer or dewaxed shellac also helps your final coat go on smoother.
And you use less of it. And you use less of it, yeah. 'Cause you're getting some build. Right From the shellac. Mm-hmm.
Very, very easy to apply. It's very, very watery. So I think, do you spray it? I do spray it, or, sometimes, I'll even apply it with a rag. Yeah, so I typically spray.
It handles really, really easily, 1.3 millimeter tip, and an HVLP sprays very easily. And then once it cures top, cut over that. And then another, I think an important thing was when I first explored this, a finishing company told me I had to let that dewaxed shellac cure out for seven days. Whoa. To make sure it was completely dry before I put water base over the top.
Sure. But I think that was just kind of a CYA answer from them. Best practices. Yeah. And in the real world, what I found is, honestly, it flashes so fast Mm-hmm.
that within a few hours overnight, for sure, that's dry enough to then put a top coat on. And I do de-scuff a little between. I do, yeah. And sometimes, you'll get little dust nibs in it that settle and if you knock those down, you'll get a really perfect finish. Yeah, so same for me.
220, 221, whatever it takes. 220, after the shellac is dry, and then it's ready for the top coat to go on. Anything else you wanna say about this amazing product? You need to just have it in the shop all the time. Yeah, keep it with you.
It's fairly inexpensive. You can use it all the time. It's universal. It's a good thing to have around. Well, and historically, what I've heard, and this could be urban legend, is that this was originally just called shellac.
Oh. And then where people got kerflooey with shellac was dewaxed versus waxed. Sure. Which is another topic we've talked about elsewhere. So, they would grab some form of shellac, use it as a base coat, put a top coat over it.
Got it. And they'd get in trouble, 'cause it was actually a waxed shellac that the top coat wouldn't stick to. So from a- We learned that. Yeah. So, from a marketing perspective, this company changed this from calling it shellac, and it's actually a one-pound cut of shellac, to calling it seal coat, because it got a bad rep as a shellac.
People thinking other stuff wouldn't stick to it. But that's 'cause they were picking the wrong shellac. This is very specifically dewaxed. Right. And that may or may not be true, but, you know, I don't like to let the truth get in the way of a good story.
spread rumors over here. Yeah, yeah. Big advocates here and here. Yep, big fan. Go get some dewaxed shellac in your shop.
Great discussion of a very helpful product. I also love the Mr. Mom reference.
"220, 221-whatever it takes" That was good.......but, like most of George's jokes, I think most people missed it 😂
Do you normally scuff sand the shellac before topcoatong? I always have but never knew if it was required. I was also advised that you can use dewaxed shellac over cured or uncured oil, like linseed or tung. Any input on this? I'm doing it now for some bottle openers I made with verawood, Osage, gaboon, blood wood, padauk, and other exotics. The oils color run were the reason for the shellac, but I used BLO on the verawood and Osage to emphasize color.
I am not familiar with dewaxed shellac. You say it can be used under anything . Does that include exterior stains that might be used on a deck or epoxy used on a table for outdoor use? Can it be used with poly urethane? Is Shellac stable in the sun?
Can this be used instead of primer when painting a piece of furniture?
IF shellac is used as the sealer, do you not follow that up with a primer and then top coat?
Two Questions: 1. Can you use dewaxed shellac as a seal coat before using epoxy? 2. Can you use dewaxed shellac on a cutting board before applying Odie Oil (for example)?
One of the best tips I've seen on here! I never realized what this was intended for. I will be starting to use this in between staining and finishing projects. Thank you! Mike
If you're going to stain the wood, you need to do that first! I have had difficulty finding any type of shellac in the Houston area until very recently. I have not found any of the Seal Coat and have been using regular Zinsser shellac for years, usually the clear variety. Whether dewaxed shellac is better than the regular kind is somewhat controversial. (I used to spray lacquer, but it's super-toxic, very difficult to apply onto larger surfaces and difficult to obtain. It also crazes, so even though it dries in 20 minutes, I rarely use it and when I do, it's on top of shellac. As you said, it is incompatible with polyurethane and both are incompatible with the silicone in furniture polishes like Pledge.) But as an undercoat for the acrylics and oil-based polys, I've had no problems with compatibility using the regular shellac. As far as a seal, I use it on my work bench which has an MDF top. It helps make it water-resistant, but not totally water-proof. I have had problems spraying it, however. It seems to dry on the tip of the sprayer about every 10 seconds, which is very annoying. I don't know if it's due to the sprayer or the shellac. Keeping it on the cool side in my spraying room helps a little, but summer is on the way. It can result in applying too much shellac and creating puddles, which dry leaving uneven edges that are difficult to sand off. I prefer smoothing it using 0000 steel wool, unless the next coat will be acrylic (that is, the water-based so-called polyurethanes) due to potential rust concerns from any residual steel particles. I usually wait overnight to apply varnishes over shellac, but I've not encountered problems after waiting only 2 hours. I would imagine that the Seal Coat being thinner might spray easier. When I run out of my gallon or regular, I'll look again for the Seal Coat. Presently, Home Depot sells it online in case (2 gallon) quantities for around $90. That's a lot of Seal Coat to buy if someone is doing only a small project. By the way, if you have a grainy surface that you need to get very smooth, like genuine mahogany, stain, shellac and then acrylic works very nicely. Since it is water-based, the surface tension lets the acrylic form a smooth, level surface when it dries (I usually wait 2 days). Then, you can still apply oil-based poly on top of the acrylic to get the surface harder and to make sure it is alcohol-proof (the acrylic doesn't tolerate alcohols, poly does).
You are spot on. I use the Zinsser sanding sealer on most of my hardwood projects. A couple coats and it pops. A few coats of polyurethane and you are done.