Cedar and finishes

[rjwoelk]

I am looking at using some western red cedar for door trim and window trim baseboards.
I did apply some minwax tong oil to a sample, liked what i saw brings out the color .
  This will be for interior and exterior,or
should I use perhaps the teak oil product,
can or should this be covered with a sparvarnish afterwards?
Thanks .Bob

[lewis]

there is a thing called tung oil finish that is applied after the tung oil i have been told that if you apply it with out using the tung oil first it will not bring out the color ,please let me know how it turns out,I have western red cedar ceilings in my house to finish and thought I would use tung oil with the tung oil finish on top   

[rjwoelk]

I have given it a couple of coats, looks good, they have a minwax finish which I believe is for furniture.  I am thinking a coat or two do a sanding to knòck off the rough fibers and it should be good for trim work.

[xlogger]

I've got a small outdoor red cedar project to finish that I want to stay as red as it can. I see where Poston soak one of his out houses with diesel and tongue oil, that he said really brighten up the color. Is this better to use than poly or what might be the best to use so it might last.

[69bronco]

I've got a small outdoor red cedar project to finish that I want to stay as red as it can. I see where Poston soak one of his out houses with diesel and tongue oil, that he said really brighten up the color. Is this better to use than poly or what might be the best to use so it might last.

Don't use poly on an outdoor project or you will be in for sanding/scraping shortly.

[GeneWengert-WoodDoc]

The color of wood changes because of oxidation.  This oxidation is increased greatly by ultraviolet light, and increased more slowly by visible light.  Water can help grey color the wood as mold and mildew form which destroy the outer most layer of cells.  To reduce but not prevent the loss of color, use a finish that prevents wetting.  A clear finish with an ultraviolet absorber will help, but I do not know of any.  So, we are left with using a finish that dyes or stains the wood.  Most or all of these are still affected by oxidation from light.  The final option is to apply a non-transparent coating (paint or film-forming coating) that obscures the grain and natural color of the wood.

We do need to be careful about anything we put in wood that might cause increased flammability or increase health risk for humans or damage the environment.  As one example, lead and mercury can no longer be in finishes in spite of the fact that they provide some benefits.

[Don P]

That's one I've wondered about. Don't oil based or poly type finishes make the wood more flammable?

[xlogger]

Not too worried about flammable, this is a cedar barn looking cover over the mail box and the post.

[GeneWengert-WoodDoc]

It may evaporate or it may increase flammability.  The big issues are the noxious gasses that such coatings emit during a fire.

[Don P]

Good point, rarely is it the flames that get you. I keep having the feeling that I'm applying an accelerant though. I wonder if there are any clear coatings that would act as a fire retardant or intumescent.

For exterior I don't like film forming finishes unless you can maintain it perfectly. If water gets behind a film and the wood cannot readily dry the moisture level in the wood is going to quickly get into the rot range. If the finish is more porous like stain vs paint it will repel liquid water but let water vapor trapped in the wood back out when the rain ends. They fail more gracefully but don't last as long. What I've found in log construction, so big wood sections exposed to the weather, you can keep recoating with those finishes till they form a film and you're back to the film problem. They need to be stripped back to bare wood periodically to keep that ideal water repellant breathable finish. Thinner sections like siding that can readily dry to the backside are more tolerant of a film.

[jim blodgett]

I think western red cedar is a poor choice for high wear trim like door casings or base board.  It would be better for window casing, but again, far too soft to stand up long as a window sill. It will look great for a short time. 

If you do decide to use it you can increase the density a LITTLE by finishing with an oil modified polyurethane, which will penetrate the pores and toughen the surface a LITTLE (highly technical term, I know).  You have your choice of gloss in these finishes, but like all surface producing finishes once the surface has been damaged (because the wood beneath it got dented or torn) it is difficult to repair.

Shellac and lacquer finishes are easier to repair than urethane but don't provide as hard a surface. A really good primer on finishing wood is Bob Flexner's "Understanding Wood Finishing" - I'm pretty sure you could track down a copy.

But no matter what finish you choose, that WRC is soft and will not wear well over time as door casing or baseboard. And it's going to get dark, trending toward mahogany dark if exposed to direct sunlight.

Facts of life.

[ScottCC]

A beautiful way to trim out a window is make the sill granite and the rest in this case cedar.  A material change for this only adds to the look without pointing out the obvious.

[jim blodgett]

Oh yeah, Scott, that does sound nice. Plenty durable, too.

Plastic laminate makes nice window sills too. Easier to work with than stone and cheaper by a long shot.

Seen lots of tile window sills over the years too.  I'm not a big fan of that but I get it - durable and easy to work with.

Granite sounds nice.

[ScottCC]

Laminate does sound cool, certainly more budget friendly.  My granite guy charges $100 per window.  Water and other stains are now handled.  Next is the oxidation and discoloration.  The longest lasting until oxidation I have found is a water based poly by minwax.  But still goes bad after just some more time.  However on pine I rub a white wash on to stain wood to a just cut look, then poly.  Knots give it away in a couple of years though.  Still, after 6 years in kitchen my pine looks good otherwise.  Don't know what color would work for cedar though.

[rjwoelk]

Thanks for all the ideas. All food for thought.