Doing a small project for myself and given it happens so rarely Im of course over-thinking the most simiple of projects...

Have a beautiful outdoor elevated covered porch/deck. Its somewhat like a treehouse. 15' off the ground on the high side, 15x30, fully covered and screened 4 sided and below the deck. Ceiling open to the ridge with trusses. Overhangs and gutters.

Inside... 3 rigidly affixed ceiling fans (not on poles) attached to bridging between the truss bottom chord. White, exterior fans, but the blades are deteriorating.

Im planning to CNC some type of cool fan blade shapes and mask off the white fan bodies and paint the bodies a different color but really want to come up with a shape/material (thinking Walnut) to CNC new blades out of. These fans see zero rain (other than wind blown mist/fog) and zero sun other than reflected/indirect.

Ive cut fan blades for people before and balanced them on a gram scale in the shop that we use for measuring finishes. These being rigidly affixed fans Im not worried about the unbalance but of course want them close.

1/4" plain sliced walnut ply is convenient but makes me nervous even with the limited exposure and a good UV clear, but solid wood that thin also twists me up.

Jalopy mode will have me re-sawing a bunch of walnut drop material over size and plane/sand for solid. Im thinking order some longer screws and run the blades .3125 or .375 solid material, clear them and balance them to .1 gram.

you know the solid wood is they way to go... might as well do a maple inlay as well, its only time right?

Make your own laminations from solid walnut and epoxy.

I would use 5-ply 1/4" if you can find it.

If not, you can make it easily enough.

MarkB:

I would consider using marine grade Baltic birch and put walnut (or whatever) veneer on both faces with either epoxy or Unibond. Whatever clear finish you would ordinarily use on an exterior door should provide adequate protection.

I wonder how much the look matters, as my ceiling fans are on all the time, and as such almost anything looks good as a whirling blur.

Hope this helps.
TonyF

Yeah I'm with Tony, I'd make these out of 1/4" marine grade and just stain them whatever color looks good as a whirling blur.

If you really want to dress them up, put a contrasting color onlay on the tips before you put the clearcoat over it.

Agreed on the spinning Tony but spring/fall, over night, cool days, etc. these sit still plenty and if Im going to be CNC'ing 15 blades anyway, doing something unique on the shape is no more work. I like the idea of skinning a ply core. Be a bit less work than laying them up completely. Plain sliced walnut was a cheap out/fast option but like Hen Bob says its only time (which I have too little of). Thanks for all of your input.

While the mechanic drives a jalopy, that car is often more reliable than a more visually attractive car. The mechanic has gone thru all its systems and repaired or renewed so as to make the vehicle reliable. He/she knows that the purpose of a car is reliable transport from A to B.