UV Protective Finish for Interior Furniture

Re: UV Protective Finish for Interior Furniture

It sounds like something suitable for exterior use is what will be UV resistant. Water-clear finishes are usually water based and acrylic or urethane to my knowledge.

Festool and Osmo (and others I'm sure) have oils with UV protection built in.

https://toolsforworkingwood.com/store/item/OS-UVP.XX

https://www.woodcraft.com/products/surfix-outdoor-linseed-oil-5-liter

https://toolsforworkingwood.com/store/item/MP-OO.XX

You have a difficult set of requirements. Those products sound close to meeting your needs but I have no experience with any of them. I'm interested to hear other's input.

Re: UV Protective Finish for Interior Furniture

Steve, I used QS Wenge for the stair treads to my bedroom loft 40 years ago, and I don't believe it hasn't gotten any lighter, and there is a 3' x 7' skylight just above the top landing. I don't recall what finish I used for certain, but I'm sure I didn't stain it. It is all 8/4", and I do recall the first time I milled some that inside it looked about the color of yellow pine when I first cut into or planed the surface, but it only took a few days to darken on it's own. My advice to you is don't worry about it fading. 

Re: UV Protective Finish for Interior Furniture

That's interesting information. Some of this veneer was stored for several years in the rafters of a shop with clerestory windows and the exposed ends did lighten considerably. I'm thinking now that an outdoor finish with UV blockers will do the job. Thanks.

Re: UV Protective Finish for Interior Furniture

Thanks for the suggestions. I'm going to do a test with one of the outdoor finishes and see how it stands up to direct sunlight for several months this summer.

Re: UV Protective Finish for Interior Furniture

UV blockers, such as in spar varnish, work by absorbing UV photons, but in the process are destroyed.  Several years ago I read that on boats spar varnish needs to be lightly sanded and re-coated every year or two, and sanded back to bare wood and 3 or more coats applied every 5 or so years.

Re: UV Protective Finish for Interior Furniture

Some turners that I know report that they have had success with using a finish that brings out the grain and then using a high-UPF sunblock as a wax over the finish. That has reportedly helped with maintaining the colors of both purpleheart and flame box elder.

Thanks to All

It seems possible that the wenge won't fade and that it would not be possible to prevent fading permanently. The idea of using sunblock is interesting, too. I've put a small piece of wenge on a south-facing windowsill and will watch what happens this summer.