While working with solid cherry wood as well as a quality veneer cherry plywood for the carcass of my current project, I wanted to use a natural finish that would not only bring the two wood types closer together aesthetically but also compliment the piece as a whole. To accentuate the beautiful grain in the cherry as well as the curly maple table top and walnut accents I decided to go with a shellac finish. I use ‘friendly finishing’ products in my work as much as I possibly can and this time is no exception. Shellac was chosen and really- what could be more natural than that? I think there are many misconceptions about shellac and I hope this article will shed some light on this unique and ageless product.
Shellac- just what the hell is it anyway?
Shellac flakes before the mixing process begins
Shellac is a resinous secretion produced by the female Lac Bug Laccifer(Tachardia) lacca Kerr (Fam. Coccidae) in forested areas of Thailand, India and China. Sounds a bit disgusting doesn’t it?
Millions of these tiny insects feed on tree sap while secreting this lac ‘resin’ and when enough of this resin accumulates on the tree branches, they’re harvested, processed and sold as dry flakes that look like the first picture here on the left. What we get is a completely organic product that is used for not only wood finishing but is also used in medicinal products and candy coating applications. Shellac can be dated back to ancient times and cultures up to 3000 years ago and in one document it is said that an entire palace was built using shellac resin!- I imagine it must have looked as if it was made of gold or glass- incredible. (yet still a bit disgusting)
Mixing Shellac
Wide mouth containers with screw top lids and denatured alcohol are needed to mix your own shellac.
As mentioned, shellac is purchased in a dry flake and needs to be mixed before using; this is best accomplished using denatured alcohol. In Canada, finding denatured alcohol can be tricky business but I managed to locate it here in Toronto at a chemical supply house; an alternative may be isopropyl which you’ll find off the shelf at most hardware stores. I should also mention that my shellac flakes were purchased at Wood Essence Distributing, a Canadian supplier of specialty finishing products located in Saskatoon, SK. They’re competitively priced and delivery took less than 5 days. Click the link to visit their website.
So back to the mixing process; I think most woodworkers can get a little nervous with the ‘ pound cut’ jargon and the methods of mixing can be both confusing and intimidating. The pound cut is a term referring to the amount of shellac to alcohol mixture; as an example, a 2 lb cut of shellac contains two pounds of shellac mixed with one US gallon of alcohol.
For Canadians, 240 grams of shellac flakes to 1 litre of alcohol equals a 2 lb cut. This idea of mixing weight with volume can get tiresome so an easier method is to just think of the viscosity of the liquid and don’t worry about the actual pound cut.
For a light sealing coat, mix the shellac to the consistency of skim milk ( 1 lb cut) and apply. Think of it as a sealer or primer coat. For general wood finish use something closer to whole milk or coffee cream (2 to 3 lb cut). The beauty with shellac is you’ll be using more than one coat and each application builds and ‘mixes’ into the previous creating that depth and luster a shellac finish is known for. Another nice thing about shellac is its compatible with other finishes like oil and wax.
Shellac flakes can be quite large so pre-grinding will make the dissolving process go much faster.
Some shellac flakes can take a few days to dissolve so what I’ll do first is take the flakes and grind them up smaller either with an old electric coffee grinder or just a mortar and pestle. (unplugged wood shop remember…just kidding!)
The smaller the flakes are before mixing the solution the faster they’ll dissolve and the less you’ll need to strain out before using it thus reducing waste. Once mixed you can place the container in a sink of hot water as well as shaking the solution frequently to encourage the dissolving process along. My method is to mix a generous amount of flakes with alcohol to create a thick blend almost like a concentrate; this is left to sit for a day or two and then this concentrate is strained and stored. The mixture will need to be diluted as needed in a different container and can easily be mixed to the desired ‘cut’ as needed.
I’m using a blond shellac as well as a dark garnet so I mixed my blond to approximately 1 part shellac to 3 parts alcohol while the garnet is about half and half. Again these measurements aren’t really that important- just use your own judgment and experiment until you find a suitable blend. The blond mixture is for the maple and will also act as a sealer or primer coat on the cherry before the richer colour of the garnet is applied. This will make for a more even finish and help to prevent runs or patches with the garnet. This darker shellac will still allow all of the beauty of the wood grain to come through but like I said earlier its an attempt to bring the solid cherry closer to the veneer in appearance.
Shellac can be applied with a brush, pad or rag or can be sprayed on but as you know here in my work space the later isn’t an option. Also, because of the sheer size of the panels in this project I’m going with a brush application which will spread the shellac much faster than if wiping.
Blond on the left and dark garnet on the right- freshly mixed they'll need to sit for a day or two.
I should mention that once mixed, shellac has a shelf life (like all organic products) so I only mix enough for the project at hand reducing waste later on. Make sure if you’re mixing shellac in your own work space to keep it away from open flame – shellac solutions are flammable and proper handling and storage procedures should be followed. Cheers!
14 Comments
Hi Tom, nice to hear about shellac. Hoppe you will keep us informed of your progress with this finish! Just read your post again and you will find that you transfered 1 us gallon to 1 litre… I’m not sure it was what you wanted?
Cheers
David
Hey Tom,
I’m not too sure I agree that “a brush application which will spread the shellac much faster than if wiping”… From personal experience, on a large panel, a nice cotton pad full of shellac is faster, easier to apply and won’t leave any brush marks.
I’ll use a good natural bristle brush for tight corner and smaller surfaces though.
Another advantage I see in brushing shellac is that you can apply a thicker coat and use a heavier mix but this can be tricky as the open time for shellac is quite short and such an approach can lead to a lot of brush marks and overlapping brush strokes will be difficult to smooth.
Remember to work fast as shellac dries very quickly. When applying to a table, you can apply three coats of shellac to the table legs in under 15 minutes. By the time you finish the fourth leg the first one is already dry.
That is if you’re using a low shellac dilution which is what I get best results with.
Take care,
Luis
Hey David,
thanks for the comments- I’ll keep you posted when I get to the finishing. As for the mix it does sound confusing but I didn’t ‘transfer’ 1 gallon to one liter- What I meant to show was a 2 lb cut is 2 lbs of shellac dissolved in one gallon of alcohol as well as a 2 lb cut is 240 grams in 1 liter….different end volume but still a 2 lb cut in both examples. This is exactly why I suggest not using the pound cut references and judge by viscosity- the pound cut jargon is too confusing!
cheers-
Luis-
I’ve been experimenting with both wiping and brushing and was finding the brush working a little faster…I think I should try using a larger pad and see if I can hold more shellac and speed up the process- that seems to be the reason I was getting further with the brush. I’m using a 3 1/8″ wide, double tapered, hog bristle brush to apply and haven’t had any problems with brush marks yet…. YET.
thanks for the comment-
Tom,
Thanks for the nice overview! Just a quick question: Do you apply oil before shellac? I have read that this pops out the grain, but I just can’t imagine that the shellac is compatible with oil. And, if you use oil, which kind?
thanks in advance,
Michael
Michael,
as strange as it sounds, shellac can be applied over oil- I have only used Tried and True but have read that linseed oil is fine as well. Maybe readers with experience in this field would leave some comments and share some thoughts.
thanks for the comment-
cheers!
Nice article Tom! I love shellac. What other finish can you complete all of the coats with in a single day?
As for the oil under the shellac, linseed works fine. However, after a few coats of shellac, the benefit is all but lost. The oil “pops” the grain initially, however, the shellac covers this up after a few coats. It really comes down to refraction of light. Once the shellac film is applied, it refracts the light the same, regardless of what is under it. So while the oil looks nice initially, once several coats of shellac are applied, the “grain pop” you are seeing is a result of the light refraction through the shellac film, not the oil. FWIW, several coats of shellac alone will “pop” the grain the same as oil under shellac. This really applies to just about any film finish that sits on top of the wood, not just shellac. Give it a try!
Hey Bob,
thanks man! Nice to get some solid feedback on using oil under shellac…
Cheers
Tom,
From personal experience, shellac will go very well on to of boiled linseed oil and from what I read it can be successfully applied on top of every finish and even better, it can be applied between incompatible finishes.
Say you want to finish a piece with water based varnish but first what to pop the grain with an oil. Acrylic varnish won’t cure on top of an oil finish but if you apply a coat or two of shellac between the oil and the varnish then the shellac will seal the oil finish and the acrylic with cure on top of the shellac.
Another use is when finishing exotics. Some species like cocobolo has a natural oil in it and some finishes won’t cure properly on cocobolo. A sealer coat with shellac will solve the problem.
I never go for a thick finish with shellac, I like a finish to have as thin as possible so I can feel the texture of the wood. Some may like it and some don’t. To me, a glass smooth finish on top of a open grained wood like walnut looks fake. But with a thin shellac finish you can still see and feel the pores in the wood and all the wood grain texture.
Some may look at it and think the finishing process isn’t complete, but to me it looks very organic and the wood kind of asks you to touch it.
With that said, my best results are with very diluted shellac, something about 1/2 pound cut. I mix it by eye and feel and I tend to use something that flows like Irish whiskey.
Don’t worry, I always think safety first and never mix shellac with Jameson…
For those who want a quick and easy shellac finish; simply buy a quart of Zinsser Amber Shellac at the hardware store and thin with denatured alcahol 1/1. Like most finishes apply thin coats. I’m like Luis and use a rag for large surfaces and a brush for tite areas but only use the brush to apply the shellac and the cloth to wipe access. This method works well because one can control the color. Just add more coats to get a darker tone.
As for a finish you can apply “all in the same day”- Generals High Performance Top Coat. Brush thin and leave alone. Drys for next coat in 15 minutes and I’m yet to have brush strokes.
I just finsihed a large project using this method and applied the top coat for durability. Doesnt get any easier and looks great.
Never used Jameson but Hennessy works well….
Luis and Jordan-
thanks guys!
these are fantastic tips…I think we have a lot of great information gathered here on the topic-
my thanks for everyone sharing some thoughts.
Cheers!
I too am thankful for all these great comments and information, as I have zero personal experience with shellac. But I most appreciate Luis’ description of the thin application. I have always had the (apparent) misconception that shellac results in a thick plastic-like fake coating which would be a turn-off for me. I have read much praise over shellac in the past and am glad to hear all these benefits can be obtained without the ugly result I’ve always pictured in my mind.
Thanks
Zinsser Seal Coat is a dewaxed shellac, but I’m not certain that the Zinsser Amber shellac is dewaxed. The waxed shellac may not be compatible with all finishes!
Hey Klaus,
If you don’t rub the shellac with some steel wool or a synthetic pad it will have a plastic feel. By this I mean that when you slide your hand over the surface it will drag. By rubbing the shellac and then applying some wax it will then feel silky smooth to your hand.
If you don’t want to apply shellac you can buff the dull surface with a polishing compound. I’ve never tried this but I’ve read about it in Jeff Jewitt’s book “Great Wood Finishes” which I highly recommend.
This way you can bring the sheen to the desired level, either a satin look or a glossy finish. See my comment in the next post for more details of my process.
Donna,
You are absolutely right, shellac is compatible with all finishes but only the de-waxed flavors. Waxed shellac won’t be compatible with some.
You can see if your shellac is waxed or de-waxed by looking at it in a glass container. A de-waxed shellac will look translucid like tea while a waxed shellac will look like you added milk to your morning tea.
After some time the wax will drop to the bottom of the container and you will see a residue at the bottom. Give it a shake and you’re ready to go.
Take care,
Luis