Monday 4 July 2016

Burly Canadians

This is essentially just pointless spitballing, part of my continuing quest for a "Canadian" ship.

The woods that could be reasonably used for a Canadian-built, ocean-going warship in the Napoleonic Wars are some soft woods, notably tamarack, and, for hardwoods that would not need to be transported 1000miles, it is limited to red oak, or bur oak. Red oak is more plentiful, but not good for ships. Bur oak is found in limited quantities in New Brunswick, is related to white oak, and compares favourably in all categories to both it and English oak.



BUR OAK
Tree Size: 80-100' tall, 3-5' trunk diameter
Average Dried Weight: 45 lbs/ft3
Specific Gravity (Basic, 12% MC): .57, .72
Janka Hardness: 1,360 lbf
Modulus of Rupture: 10,920 lbf/in2
Elastic Modulus: 1,040,000 lbf/in2
Crushing Strength: 5,890 lbf/in2

ENGLISH OAK
Tree Size: 80-115' tall, 3-5' trunk diameter
Average Dried Weight: 42 lbs/ft3
Specific Gravity (Basic, 12% MC): .53, .67
Janka Hardness: 1,120 lbf
Modulus of Rupture: 14,100 lbf/in2
Elastic Modulus: 1,544,000 lbf/in2
Crushing Strength: 6,720 lbf/in2

WHITE OAK
Tree Size: 65-85' tall, 3-4' trunk diameter
Average Dried Weight: 47 lbs/ft3
Specific Gravity (Basic, 12% MC): .60, .75
Janka Hardness: 1,350 lbf
Modulus of Rupture: 14,830 lbf/in2
Elastic Modulus: 1,762,000 lbf/in2
Crushing Strength: 7,370 lbf/in2


So what does all of that tell us?

Bur oak is
-bigger than white, not as big as english
-lighter than white, not as light as engligh
-floatier than white, not as floaty english
-10 harder than white, 240 harder than english
-ruptures more easily than both (and all ship woods)
-not as elastic as either
-both those numbers are about 30% less than english, and a little bit more for white
-crushes more easily than both, but not as drastic as rupture and elastic

CONCLUSIONS:
Sailing performance would place it between english and white, if built similarly (and at all well).

Damage performance is harder to conclude. While harder than either, its other properties make it more prone to splintering and breaking. Perhaps, if expressed in video game terms, this would mean higher HP but lower armour? How then do those terms apply to the real world? So janka is, shall we say, general wear. Rupture and elasticiy are sudden impacts. So janka is hp, is structure. R and E are armour. Therefore bur oak is less armoured than english or white. Upwards of 30% easier to penetrate. Presumably. But a lot of the "fir" is going to have similar characteristics, so bur is something of a compromise. Now, if built well and properly, possibly that penetration problem can be mitigated. With, say, close framing. 3", perhaps.

I'm happy with this. It's interesting, too, that bur oak is so in the middle of the english and american oaks. How very... Canadian.

So. Now the problem is that there were no facilities in Atlantic Canada to build anything bigger than a sloop. But I want something bigger than a sloop. And the Navy didn't like colonial wood that had been shipped. The journey was hard on it.

I suppose it's possible that, as a Captain who had to put in for repairs, some rich and influential Lord, as an admiral, returned to Canada to build a frigate, during Spencer's permissive and experimentative reign. But ultimately, I don't honestly think I can reconcile the idea without going full alt-history, so my Canadian ship will probably have to stay as a sloop, if I ever make one.

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