Gunwhale wood considerations

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ash
- 42 lbs per cubic ft
- hardness 1320
- rupture 15000
- crushing 7400
- elastic 1740000

- perishable / slightly durable, easy to steam and work in general

cvg fir (numbers for red fir)
- 27 lbs/ft3
- hardness 500
- rupture 10370
- crushing 5410
- elastic 1483000

- (red fir) perishable, easy to work

meranti mahogony
- 30 lbs/ft3
- hardness 550
- rupture 11200
- crushing 6120
- elastic 1652000

- perishable / slightly durable, easy to steam and work in general

hard maple
- 44 lbs/ft3
- hardness 1450
- rupture 15800
- crushing 7830
- elastic 1830000

- non durable to perishable. Can burn when cut (routed) can blotch when stained. Fairly easy to work.

white oak
- 47 lbs/ft3
- hardness 1350
- rupture 14830
- crushing 7370
- elastic 1762000

-  black stains from water ingress
- very durable, shrinks a lot but good workability, steams well. Avoid iron contact (can react)

iroko
- 41 lbs/ft3
- hardness 1260
- rupture 12700
- crushing 7840
- elastic 1360000

- rot resistant, easy to work, some tearout, glues well

sapele
- 42 lbs/ft3
- hardness 1410
- rupture 15930
- crushing 8740
- elastic 1746000

- moderate to very rot resistant, difficult to work

Approximate wood volume:
Outer: 12 * 12" * 6/8" * 5/8" = 67.5 cu in
Inner: 8 * 12 * 6/8" * 3/8 " = 27 cu in
Total (two sides) = 189 cu in (189 / 1728 cu ft = 0.109 cu ft == 4.8lbs @ 44 lbs per cu ft)

And add some 1/8 trim at the front for aesthetics (0.1 lbs).

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