I need some shellac advice…….
I’m planning to shellac some stair parts, a big newel and rail parts. All are mahogany. The newel is turned and varies from 3″ to 6″ in diameter. The rail and related parts have machine shaped edges and tops. So here are my questions:
Do I need to do additional sanding? To my eye, all of the surfaces are the equivalent of having been sanded with about 120 grit sandpaper.
One of my favorite finishes is one or two coats of shellac followed by wax. Is that sufficient protection for somethig that will get a lot of hand traffic?
Your opinions are greatly appreciated.
Replies
Go to Breaktime. He's always hanging around there.
Quickstep,
Hi,
it depends on what you want to achieve with the shellac..
If your goal is a high gloss finish 120 grit is too coarse and will result in dull satin like finish. If you seek a high gloss I suggest do it all lightly in 150 grit, 180 grit, and 220 grit, I might even go to 320 grit.
When you sand all you are doing is sanding off the coarser scratches left by the coarser grit, real lick and a promise stuff but you must get everything..
If you jump grits you add dramatically to your sanding time. or risk not getting out the scratches from the earlier grit..
Frenchy,
I don't mean to highjack the thread, but when you use shellac on a floor, do you worry about waxed or dewaxed?
Shellac is my favorite finish, and I will be using it on the next floor I do.
Thanks,
Fred
Froed
For floors I use Zinsser's bullseye shellac "blonde" You use enough that it doesn't pay to try to mix your own from flakes and it's cheaper that way. If I wanted a darker finish I'd use their Garnet but most of the places I buy it at don't have much of a turnover or don't stock the Garnet colored version.. they say that you can tint by adding up to 6 0z of universal colorant which might get you the color you seek..
The Zinsser shellac that is blonde is SealCoat and it is dewaxed. Zinsser doesn't make a garnet shellac, only one named Amber. Amber is basic orange shellac, it does contain wax. Zinsser also makes one they now call Clear. I would not recommend this for floors, since the process that makes it extremely light colored is chemical bleaching. The result of that makes the Clear less water resistant than the others. Seal Coat dewaxed is also a bit more water resistant than the Amber shellac with wax, but the difference is less meaningfull.
Steve
Hmmm,
I'm sitting here looking at a can of Zinssers bulleye shellac and right there at the bottom it says clear. I happen to have a few empty gallons of it sitting around because I've been shellacking my timbers lately..
Uhh, no that's not a euphemism for something sexual ;-)
Yes, Zinsser makes a bleached shellac called Clear (it used to be called White, but that was confused with their pigmented shellac stain sealers). Clear is made by bleaching orange shellac with a chlorine bleach. (The term "orange shellac" comes from the commodity trading of shellac before Zinsser further processes it and puts their brand on it. Zinsser Amber used to be named Orange.) The chemical bleaching process leaves the shellac less water resistant and generally less durable than unbleached shellac. White or bleached shellac is not available in flakes because in dry (powdered) form it deteriorates very quickly--a matter of days or hours I believe, but has a more normal shelf life when mixed with alcohol.
Blonde (including Super Blonde and Ultra Blonde brand names) are not bleached but have had the natural dye removed by a charcoal filtering process, and consequently retain more water resistance than Clear, even though they are nearly as light colored. Seal Coat is basically a blonde shellac--not quite as light as Super Blonde or Ultra Blonde brands available in flakes--that has also been dewaxed, and processed to give it greater shelf life in the can. Dewaxed shellac, whether from can or from flakes, is more water resistant than shellac that retains its natural wax.
Edited 11/20/2007 4:23 am ET by SteveSchoene
Machined surfaces definately need sanding. When you apply finish, especially shellac which will raise the grain just a little, the ripple effect that comes from rotary cutting tools such as planers and shapers seem to be magnified. You also want the final sanding pass to be done by hand, with the grain, using the same grit as your final ROS sanding. It won't take much, but this does seem to clarify the finish by removing cross grain swirls.
It is good to work through the grits, but by no means essential--not worth getting in the car to get some 180 grit to use between 150 and 220. You add a little time using finer grit, but generally take off less material. The time difference is only dramatic if you stop just at the point when you have replaced all deeper scratches with the finer scratchs from the next grit. But most people sand too much with each grit, so the practical application isn't as great it might be if done perfectly.
One or two coats of a light cut of shellac (2lb. or less) is pretty minimal particularly on an open pored wood like mahogany and on turnings which have a lot of end grain. You don't need to build a heavy film, but you should have enough to give an even coating. If you apply several coats and then sand until you just about cut through, you will significantly reduce the visibility of the pores.
The wax adds very little to protection. Besides you need to grip the stair rail should you start to fall, not slide on it.
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