Shellac Masters: HELP!

[Prashun Patel]

Here are some pictures of a foam shellac brush (left) vs a fresh brush. Forgive the black specks, I was previously using that brush to apply dye.

I applied 4 coats of shellac to the hardboard last night, giving about 3 minutes between coats. As you know, HB drinks up shellac, so drying and streaking was not an issue.

I left the brush in the open air all night, and then applied 4 more coats with the same brush this morning.

I admit, normally, I apply Sealcoat as a seal coat, and don't try to paint on a sheen. If I want sheen I almost always spray it...

You can see that the brush still performed fine and is holding up well. There is a bit of swelling, but I am unsure if that's just from absorption in the foam. When I pull at the seam, the foam does not yet appear to be failing.

The shellac does tend to ridge once it's built up. I suspect it's two reasons: 1) The shellac on the surface is still wet and is dragging and causing ridges when re-coated too quickly. 2) I think there is probably shellac IN the brush that, once the dna evaporates, may cause a thicker cut to be applied. All this is to say, let it dry, and use a fresh brush. The nice thing about thinned shellac is that even when shaken, the bubbles dissipate quickly - unlike in varnish. This means a foam brush is perfectly capable of laying down a bubble-free coat - as you can see from the picture. But I'd use a fresh one, and I wouldn't do them in as quick succession as I have.

[John TenEyck]

Thanks Prashun. That brush looks far more normal after use than the ones with the red plastic handles I've been using. Those last a couple of minutes before swelling and turning limp.

John

[Prashun Patel]

I have been calling them JEM brushes, but I see mine are actually JEN Manufacturing.

[Frederick Skelly]

Hi Mike, (and everyone) New member here.

If I may chip in. I'm a French polisher and furniture restorer. Looking at your photo, I'd say the problems are twofold.

1. The brush. A squirrel hair brush is best for applying shellac. Followed by bear bristle. Synthetic, or coarse paint brush bristles tend to drag the polish and it drys on the thicker bristles faster than on fine bristles so the shellac goes rubbery. Those foam brushes are not much use as the polish floods out rather than being gently layered on.
2. I think you've built up your polish too quickly by the look of it so it has 'piled.' Even though shellac dries quickly, if you apply too much in one sitting, it has a tendency to build up in peeks and troughs. If you brush more polish on, you are only going to exaggerate the problem as you discovered.

As has been said. That will have to be sanded right back or stripped to get a surface suitable for polishing. And you need a good brush. Or better still, be a little adventurous and try using a polishing rubber, as you stand more chance of getting a flat, even, French polished look. You don't need to body up, just use straight strokes until you have enough polish on to achieve a soft shine.

A top tip for brushing on shellac, is to add a splash of natural turpentine to a 3/4 full tin of polish. This helps slow drying time and will maintain a wet edge which will reduce piling or ridges. And allow 15-20 mins before going back. Apply an initial coat, then de-nibb with fine 320 grit abrasive before applying the next coat.

Hope that helps?

This is great Anthony. Thanks for posting it!
Fred

[Andy Bryant]

And, whoever asked what brand the foam brushes were - here ya go. HA! I just read that. My brilliance rarely impresses me more than my stupidity when it comes to simple things.

God, do I know that feeling!! Almost as bad as buying something I already had.

[steve tomaselli]

I don't know if you have ever watched Paul Sellers but he shellaced a tool chest he built and used a Hake Brush. These brushes are used for water colors but they work beautifully with shellac. I bought one for myself and they do work nicely.They are on Amazon and the one I bought is 1 inch wide.About $10.00 with shipping.Paul Sellers has been woodworking for about 50 years and teaches also. If you get a chance go to his website I think you will enjoy him.

Steve T.