Spars: Sitka Spruce or Douglas Fir?

[colinml]

Living in the Pacific Northwest of the USA, I am fortunate to have very high quality Douglas fir just a five minute drive from my house. With a little more work, and probably considerably more money, I could get Sitka Spruce. I have the luxury of choosing between these woods.

I'm considering a hollow box spar for the Goat Island Skiff. Is the superior strength to weight ratio of Sitka worth the added expense, or would the difference be so small as to not be noticable?

[Boatmik]

That is a luxury indeed! Personally I would go with the Fir. But if you really, really want to use the spruce ... then go for it!!!

If building of spruce no changes will be necessary for the mast versions.

But the yard and boom should be increased in diameter by about 2mm ... so just add that to all the diameters in the plan.

It doesn't sound like a lot ... but it makes a significant difference to the stiffness. And we should compensate for the slightly lower stiffness of the spruce.

Best wishes
Michael

[colinml]

Thanks Michael. I think I will go with the fir. One thing I forgot to mention is that I am free to sort and pick the pieces I want with the fir, but I suspect I would have to order the spruce, and would have less involvment in choosing.

[arbordg]

Colin,

We built our GIS before Mik drew up the hollow rectangle version of the mast. Our round, solid fir stick has performed beautifully. However, I just completed a PDR using the Storer balanced lug rig, using a hollow rectangular mast. Amazing how light it is! Revising the GIS to the hollow spars has, as a result, hit the Someday List.

For the amount of wood that'll be in your spars, I wouldn't bother with the Spruce. You'll lose more in strength than you'll shed in weight.

Keep in mind, though, that straight grain is even more important in the fir than it is in the spruce. Since you get to hand pick... look for sticks with a minimum of grain runout in either direction (along the length of the stick, or thru the thickness). as well as the tightest grain (most growth rings) possible.

Good luck


"There is nothing new under the sun, but there are lots of old things we don't know" -- Ambrose Bierce

[Boatmik]

Colin,

You can PICK AND CHOOSE the fir you want.

Do you want me to die of jealousy!

Michael

[colinml]

We're completely deprived when it comes to kangaroos and koalas,however:D

[Daddles]

We're completely deprived when it comes to kangaroos and koalas,however:D

Overated as spar material :rolleyes:

Richard

[colinml]

Arbordg,

Thanks for the comments re: run-out and the goodness of hollow masts. I feel I'm moving close to beginning this project faster than I thought I would, thanks to Michael's work explicating things in the text, and the opportunity to ask about things here.

It's been a while since I got excited about a woodworking project.

[Boatmik]

Overated as spar material :rolleyes:

Richard

Just hop along there Daddles ... that's a good bloke!

MIK
(best laugh I have had this week)

[arbordg]

Just hop along there Daddles ... that's a good bloke!

MIK
(best laugh I have had this week)

Mik,

I don't know why you encourage that sort. He's probably just another one of those internet fellas who talks about stuff they have no personal experience with...

Daddles, how many spars have you constructed out of said material? :wink:

[Boatmik]

Have you two been introduced ... you are actually two blokes I would like to introduce to each other in real (rather than this virtual) life. David, meet Richard!

I think you are both similar in some ways .. so probably you will kill each other on sight!!!! (hehe - I can watch as the witticisms mount to full battle level)

MIK

[arbordg]

Have you two been introduced ... you are actually two blokes I would like to introduce to each other in real (rather than this virtual) life. David, meet Richard!

I think you are both similar in some ways .. so probably you will kill each other on sight!!!! (hehe - I can watch as the witticisms mount to full battle level)

MIK

Richard,

How do you do? I'd love to meet you in person. If Mik says a bloke is worth the powder to blow him to hell, then that's good enough for me. You two just hop on a plane... or a freighter (that might be more fun) & swing by the shop. I've got cold beer or throat-warming single-malt. Oh, alright Mik, I've got herbal tea too <G> Or, y'all could take up a collection. I'd be happy to come on down to your neighborhood and help you puzzle out how to make use of your indigenous spar-making materials.


"I'm NOT short. I prefer to think there is simply more space above my head for word balloons full of devastatingly pithy witticisms" -- R. Stevens

[Daddles]

Just hop along there Daddles ... that's a good bloke!

MIK
(best laugh I have had this week)


Mik,

I don't know why you encourage that sort. He's probably just another one of those internet fellas who talks about stuff they have no personal experience with...

Daddles, how many spars have you constructed out of said material? :wink:

I've never made a spar out of kangaroo or koala though my siamese is a very tempting option at times :oo:

Spars? Hmm. A mast, a boom, a top yard, three sets of oars - not a lot I know but I'm a late starter :wink:

Richard