Shakes?

Simes

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I am about to start shaping the bowsprit. The rather large old telegraph pole has some impressive shakes in it. these shakes bisect the circumference of the pole at around 120 degrees spacing. Each is about 1/4 inch wide by 3 to 4 inches deep. The lenth varies between a couple of feet and some 10 feet.
Given that I intend to have a large heavy band around the foot and a heavy cranse iron around the out board end how should I treat the shakes? Fill with Sikaflex? Epoxy putty? Some form of linseed oil paste?
Should I throw the lump of wood away and start again?
Ultimatly the sprit will be painted bright white so colour of the wood / filler does not matter.
Should I be treating the wood with anything prior to painting?

I thought that this was going to be simple.
Many thanks
 

Simes

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Hi Lake Sailor,

I could not agree more, the levels of O2 are not the issue here, more the amount of spirit.
 
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Telegraph pole? Must be quite a substantial boat. What sort of dimensions is this spar finishing to?
Wonder if the creosote in the pole will cuse problems for painting.
 

ccscott49

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I would look for another piece of wood, the shakes you are talking about sound substantial and a bit too far gone for my liking!
 

Peterduck

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I must disagree with Mr. Scott. A highly-respected shipwright here in Melbourne actually put 'shakes' into a fresh oregon log with a circualr saw so that he would pre-empt the shrinkage which he knew would come as the log seasoned. This way, he had a nice, straight slot to deal with. This he simply filled with a long, thin, shaped batten of the same timber and epoxied it in place once seasoning was complete. Q.E.D.
Peter.
 

Simes

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The vessel is a gaff schooner designed around 1850 as a Grand banks fishing boat.
This one was built in Fambridge by "Mick the Brick" in ferro around 1977.
The Pole is 20 feet long and 10 inch in diameter.
THere is a lot of creosote in the wood, no sign of rot. I supported the pole at the extream ends and then stood on the centre, deflection of about two inches recorded at the centre (only test I could think of) The masts are also Telegraph Poles and are massive.
the Spar will pivot at the inboard end when finnished, I could put more steel bands around the spar to clamp it closed if required.
I could cut some thin strips of pine, shape them to fit and then glue them into the shakes, what happens then if the wood "takes up"?

Simes
 

Peterduck

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Shakes originate in the initial moisture loss when timber is seasoned; from something like 25% down to 12-15%. Subsequent moisture variations will be small. Timber 'taking up' moisture occurs when it is used in underwater applications, be they planking, keel or deadwood. when wooden boats were the 'normal thing' these applications would be often made with fresh timber, straight from the forest. It seasoned during the time that the boat or ship was being built. This also helped when timber had to be steamed into shape, as thoroughly wet timber is needed for this process. The practice in Southern Tasmania was to fasten every second plank in the first round, and then go back and fasten the 'shutters' in a second round. This ensured better fits between the planks. Even with the occasional immersion in a 'green one', your bowsprit won't get the constant wetting that would cause it to swell again. The creosote will also inhibit any absorption of moisture by the timber.
Peter.
 
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Given the finished size of the bowsprit I'd not worry about a few shakes. At 10" dia. you'll be doing well to find any dry baulk without some splits and shakes. Given the restraints, and since the bowsprit will be working mainly in compression, I can't envisage a problem. Filling the cracks would only work if you could be sure of sealing the whole spar up 100%. Otherwise rain / spray will inevitably find its way in, splines / filler/ goo will tend to stop it drying out quickly. There is going to be some shrink-swell action going on constantly, so the chances of getting a "yacht" finish on the thing are slim. Given the highly ventilated position of the bowsprit rot should not be a problem.
That's all in my opinion of course. Your bowsprit is as long as my entire boat!
 

fluffc

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I have substantial shakes on my bowsprit and mainmast. Neither have broken up, and since the shakes run longitudually don't effect the compression strength of the spar appreciably.

Bung whatever you like in them to fill them up. When I cleaned out some of the shakes to tidy them up I have found all kinds of 'substances', from P38 to Sikaflex.

IMHO something flexible like sikaflex is good - and try to get it right down into the seam. Also worth considering is something which never sets completely, but just skin hardens.

By the way, what is the name of your boat?
 

Simes

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Hi,
She is named "Talisman" 45 foot on deck and 58 feet LOA. The sprit is mounted some way back along the deck.
We are living on board whilst getting ready to sail over some horizon or other.
We have stripped and rebuilt the masts with the help of "Small Craft Rigging Services"
The interior is about half way through its rebuild but with the better weather I want to work on the rig.
So many jobs and so many jobs!

I think that I will work on the sprit and then fill the shakes with Sikaflex just prior to painting.

Thanks for the help and advise
Simes
 
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