Finish for an oak medicine cabinet

[Alex Berkovsky]

Looking for a finish recipe for an oak medicine cabinet that will offer protection agains moisture. I assume dewaxed shellac sealcoat is a must.

[Casey Gooding]

Are you going to stain it??
Shellac sealer isn't necessarily a must. If you are not going to stain, you can go straight to polyurethane, varnish or lacquer. If you will stain, you can apply poly or varnish directly over it (assuming you are using oil based stain). You will need to apply shellac between the stain and lacquer (or let the stain cure for several weeks, then you can lacquer over it).

[Alex Berkovsky]

Are you going to stain it??
Shellac sealer isn't necessarily a must. If you are not going to stain, you can go straight to polyurethane, varnish or lacquer. If you will stain, you can apply poly or varnish directly over it (assuming you are using oil based stain). You will need to apply shellac between the stain and lacquer (or let the stain cure for several weeks, then you can lacquer over it).

Casey, I am not going to stain the cabinet. Which type of finish will offer the best protection from moisture?

[Prashun Patel]

I've heard it said that shellac is an excellent vapor barrier, so it can't hurt to put that on as a 'sealcoat'. But I'd use a varnish topcoat.

[Alex Berkovsky]

I've heard it said that shellac is an excellent vapor barrier, so it can't hurt to put that on as a 'sealcoat'. But I'd use a varnish topcoat.

Shawn,
Any particular brand of varnish that you or anyone else can suggest.

[Howard Acheson]

Which type of finish will offer the best protection from moisture?

A coat or dewaxed shellac followed by a couple of coats of non-poly interior varnish.

[Howard Acheson]

>>> Any particular brand of varnish that you or anyone else can suggest.

You want to use a dewaxed shellac. Dewaxed shellac is a much better moisture barrier than a shellac containing it's natural wax.

If you want a pre-mixed dewaxed shellac, the only one available is Zinsser's SealCoat or the Zinsser Spray can shellac. An option is to buy dewaxed shellac flakes and mix your own.

[Prashun Patel]

Personally, I like the Zinsser Sealcoat. If you want it colored, just drop some dye into it. Dissolving flakes is more trouble for me than it's worth.

As for varnish, I there are a few I've had good luck with:

Waterlox Original is my favorite when I'm feeling spendy (which is not often).

I've had good luck with Cabot alkyd.

To be honest, (get ready for the poly haters to bellow) I've also had very good luck with Minwax polyurethane. I've made it into a wiping varnish by thinning with mineral spirits about 50%, and I've made an Oil/varnish finish by thinning it with about 33% spirits, 33% BLO. I like the ease of application of wipe on finishes and don't mind the extra coats you have to put on. I prefer to use this on in-the-wood type finishes. When it builds, I do agree that it can look plastic. The best varnish I've used for building is the Waterlox Orig. That brushes and builds so easy - and it has great clarity. It will darken yr surface a little though.

[Alex Berkovsky]

Waterlox Original is my favorite when I'm feeling spendy (which is not often).

$38 for a quart? That's expensive! The cabinet is going into my uncle's basement bathroom as a present and want to keep the cost to a minimum. I may have to go with a poly or home brew.

[Prashun Patel]

I didn't realize it was that expensive. I get it locally for about $25/qt.

[Casey Gooding]

The shellac undercoat is really unnecessary. If you are using a good topcoat, the shellac will offer no additional protection. Actually, it will weaken the topcoat. Probably too little to matter, but Bob Flexner is adamant about it.

For the best moisture protection, I would recommend a marine varnish. Thinned maybe 25%, applying several coats. Top quality stuff is expensive ($60+ per quart). For your needs, however, something like Minwax Helmsman Spar Urethane would be plenty.

[Alex Berkovsky]

For the best moisture protection, I would recommend a marine varnish. Thinned maybe 25%, applying several coats. Top quality stuff is expensive ($60+ per quart). For your needs, however, something like Minwax Helmsman Spar Urethane would be plenty.

I see that Minwax Helmsman Spar Urethane is readily available at BORG and also comes in an aerosol spray can. For this particular application, I think it's a perfect solution.

[Casey Gooding]

I think it would work well for your needs