Sealing with shellac.

Since I will apply a water-based clear poly, I have to seal the stained wood to avoid stain smearing poly and making a mess. After doing some research, I have decided to use a dewaxed shellac sealer.

This natural product has many advantages:

• Inexpensive when bought in flakes
• Durable (you just mix the quantity you need, the dry flakes can be stored forever)
• Non toxic, it's just alcohol and "bug resin", it's actually edible !
• Easy to apply
• Warms up the color tone (water-based poly is very "white")
• Has some grain filling properties

As recommended by this webpage, I made a bottle of 2 pound-cut (two pounds of flakes to one gallon of alcohol ratio) shellac, it's the regular mix. Converted in metric system:

• 3785 ml of alcohol (one gallon) with 907 grams (2 pounds) of shellac
• 417 ml of alcohol with 100 grams of shellac

They recommend a 3 pound cut for sealing stain and filling grain, but I prefer to work with several thin coats for more control.

Preparing is pretty simple, it's basically pouring alcohol into the container, adding the flakes and putting the container in hot water, stirring occasionally.

After letting it sit overnight, it's now perfectly mixed, with no flakes remaining

Took this picture later, I've used already 50%.

It makes you ca. 485 ml (16.4 fl. oz) of shellac, should be enough for a couple of coats. I paid 6,2 euros for shellac and 2 euros for denatured alcohol. As I said, cheap.
Important notice: shellac goes bad after some time, it won't dry hard, rather gummy. So don't mix too much at once, and make it just before starting to work.

I applied the first coat of shellac using a flat brush. It's easy to apply because shellac isn't very thick and flows easily.

And the effect is wow. It really brings out the stained wood tone, adding some depth to it.

But let's be honest, there's an issue on curved surfaces, like a drum shell. If you apply a little too much and that it starts dripping down, the dripping marks will cure hard in a minute. That's what happened here and there.

I had to sand them off using 400 grit with water.

Bottom-right, you see the sanded area.

Buy the way, this step of the process proves that shellac really acts like a sealer, and sanding with water had little effect on stained wood. So I gave it a go and re-sanded lightly all the shells.

At some point, you might think that you screwed up your work. Sanding paste turns green, ouch, what am I doing? But giving up is no option.

After cleaning up "the mess", I crossed my fingers and brushed on a second coat, trying this time not to apply too much.

It went better - and apparently no faded spots due to sanding - but couldn't avoid build-up marks. Shellac dries that fast. Again, some local sanding and some cold sweat. I even had to re-stain lightly the spots where I sanded through the shellac and took off some of the stain. Brr. No pictures, sorry... 

At this point, I had to think it over. Building up thicker layers of shellac sounds good, but avoiding dripping or overlapping marks is very hard. I definitely have to find a more controllable way to apply shellac and avoid excessive sanding. Read on the next article my experiments with what I will call half baked French polishing.

Some late night tryout of what looks like the right thing to do