How to finish american mahogany for a mantle

[chris trainum]

I went to a local saw mill that had a 7" long 9" wide and 2" thick piece of mahogany. It has been kiln dried and cured in stacks for at least 10 years. I cut the board to 4 feet to use as a mantle piece above my gas fireplace. I used oak wood 4-6" wide 7" long as a background from floor to ceiling. about 9" used a light stain came out great. My question is what to do with the mahogany. I was thinking just sand it smooth than use a polyurethane matte on the board. I have read that mahogany is very porous and i should use wood filler, stain it than lacquer or poly it do i need to do all that or just sanding and poly with a matte finish. Board is beautiful the grains look amazing i don't want to get a bunch of stuff on it and take away from the beauty. Any ides of another technique?
below is a pic of the mahogany that is left after cutting from 7' may make nice shelves with it the other is the wall i built around fireplace. just to show i would hang mahogany between the tv and fireplace.

thank you for any tips or suggestions

thank you chris
IMG_1846.JPGIMG_1697.JPG

[Jim Becker]

Mahogany (assuming it's really mahogany) has an open pore pattern. The only reason you would use a grain filler is if you prefer a "smooth" surface post-finishing. That's no different from oak in that respect. Given your somewhat rustic look already in place with the oak, you'll have to decide if you want that kind of contrast in texture or not. You'll also have to decide if the natural color of the mahogany against the oak is the look you want or if you want it darker to mimic the darker colors of the fireplace insert and the TV screen. These are all subjective aesthetics that only you can decide on.

You might want to use that extra piece as a place to test various finish options before you commit the primary piece to a finishing regimen...wink, wink...nod, nod...

[John K Jordan]

For those interested, I think this is a good article on mahogany and "mahogany":

http://www.wood-database.com/wood-ar...s-the-lowdown/

JKJ

[Art Mann]

John, that is a very informative article. I hope others will read it. There is too much confusion, and outright deception, associated with the materials called "Mahogany".

[Mel Fulks]

John, that's pretty accurate and quick,thanks. I've kept track of how much waste there was with the African and real. The required project pieces have to be pretty small to save any money. For a job like "run and rip" mouldings the pieces can be so distorted off the saw that they just can't be used. Perhaps ,someday, that energy might be harnessed for good!

[chris trainum]

would you recommend a stain (something little lighter than the oak stain on the wall) than poly coat it. I was worried when i started reading about the problems working with mahogany. I get all my wood from a local lumber mill that charges pennies on the dollar.(He is retiring soon) He said it was mahogany either way 20$ for 7'long 9"wide and 2" thick beautiful board i couldn't go wrong.

[Mel Fulks]

When first "discovered" it got oil finishes. It's had everything. There is no consideration needed beyond your preference for this particular project. If you want to put one hand on the mantle while staring into the fire ...oiled mahogany feels really good!

[Mel Fulks]

I failed to mention the open pore question. They say that when it got oiled it was often done along with "brick dust". I tried real fired brick ground and sifted and could not get it fine enough to not be abrasive. Also tried unfired ground up potters clay ,and that worked .

[Mel Fulks]

One more! The thick mahogany is usually higher quality denser stuff than the 4/4 . I think the 8/4 makes your mantle a good project for the oil treatment.

[Robert LaPlaca]

I build period furniture, there is Mahogany and then there is Mahogany, the really good stuff is hard, dense, reasonably fine grained and dark. The really good Mahogany is not very easy to find and when you do it’s expensive, so for example 8/4 stock would be in the $12-15 range bd/ft.

As previously posted, filling the grain is more a matter of asthetics, I would say if your desire was for a piano high gloss, grain filling would be a slam dunk, but for for a low or matte finish, not so much.

i am kind of curious where you are located, as Mahogany is a tropical hardwood, I know that some grows in Florida, not really sure it grows anywhere else on mainland US.

I am not a fan of poly, I think I would recommend something like General Finishes Gel Finish. It applies easily with a rag, dries fairly quickly, it doesn’t build much, so although it’s not a matte finish, it would be pretty low gloss.

[Wayne Lomman]

The appearance of the pores is the common theme with all mahogany. Open grain will look good for this. If you use a film finish, apply several coats and then block it flat before the final coat. This leave a smooth and we'll defined open appearance rather than the half melted look you get otherwise.

John, the mahogany article was interesting. I worked for many years with Brazilian mahogany back when it was available. The author identifying Australian Cedar as a mahogany lookalike is odd though. I can't think of anything less like mahogany. He also left out eucalyptus resinifera which is red mahogany. Make spectacular flooring. I used messmate/white mahogany on a dining suite last year. Cheers

[John TenEyck]

Robert, GF Urethane Gel Finish is poly, just in a gel form. It may be fine for the OP'S application, but it has pretty low chemical durability, about on par with shellac. Water leaves white rings and anything stronger just destroys it. Arm-R-Seal on the other hand is very durable and is available in several sheens. It's poly, too, in full disclosure, but looks beautiful to me.

John

[Robert LaPlaca]

John, yeah I know that the General Gel finish is a poly, but it’s not quite the same animal as poly in the can, that builds that awful look. The gel finish builds to a nice low sheen glow. I think that for a mantel, its an appropriate application, unless one is going to use the mantle as a bar top..I have used the Gel finish on a houseful of trim and fireplace surround, with no issues. I don’t have any personal experience with Arm-r-seal, So it’s hard to recommend it.