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Old 16-03-2017, 14:38   #16
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Re: anyone have a boomkin and any advice on building one.

A. Don't cover wood in glass, encourages rot.
B. Upsizing rigging by one size is not going to add 20lb to the rig of a 24' boat, more like 10lb of that. 1/3 or so of the extra weight will be at deck level for up sized turnbuckles, tangs and fittings. I believe Sta-loc makes endfittings for upsized wire that still use existing pin sizes. I believe this was so owners could convert to A316 wire without taking a strength penalty by staying with the same size wire or the cost penalty of having to upsize all the fittings. If you upsize the wire not the fitting then the added weight will be in the range of 4-8lb.
C. Historically the mast weight to ballast trade off was 14:1 not 20:1. You boat would probably be in that range, possibly as low as 12:1.
D. I believe it was IslandPacket that went to solid bobstays for their bowsprits. If I recall correctly nuts were welded to each end of a small diameter stainless tube, one regular and one reversed threat. Forked or eyed studs were screwed in and there you go. Tubing length needs to be pre-planned to take into account tangs and such but you'd need to do that with regular wire too. I believe they went solid to to lengthen service life and reliability. Don't really know.
E. Article in most recent GoodOldBoat guy replaced his wood bow sprit with an aluminum box section he had welded. It was slightly lighter than the wood original and about 5x stronger per an engineer's calcs.
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Old 16-03-2017, 15:43   #17
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Re: anyone have a boomkin and any advice on building one.

If you really feel the need to increase the strength of your rigging, you could go to Dyform or Compact strand wire of the same size and reap a ~15-20 % increase in breaking strength. Has lower stretch, too...

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Old 16-03-2017, 16:00   #18
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Re: anyone have a boomkin and any advice on building one.

Yes I agree wood looks better, and Yes my boat is designed to have the bomkin. the ss is Stronger and less maintenance ,and I'm not "that" concerned with looks rather then functionality. I currently have single tangs on the stick, the ones I have for replacement I could only find double tangs so I added toggles to that so after all is said and done there would be a bit of weight added up high....haha decisions decisions decisions bump em up or keep em the same...my uppers are 3/8 pin size with 3/16 wire I could keep the 3/8 pin and turnbuckles and bump the wires up to 7/32. So not much weight there. As for the lowers they're 5/16 pins 5/32 wire was gonna jump up the pins to 3/8 and use 3/16 wire. So there's a bit of weight added.sorry I haven't done the math, but as Adeline pointed out it's only a 24' boat and my mast is only 33'. Hmmmmmm
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Old 17-03-2017, 13:59   #19
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Re: anyone have a boomkin and any advice on building one.

if its not broken don't fix it
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Old 17-03-2017, 17:06   #20
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Re: anyone have a boomkin and any advice on building one.

That stay below the boomkin; could it be a Dolphin Wyper?

Don't believe everything you think
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Old 17-03-2017, 23:48   #21
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Re: anyone have a boomkin and any advice on building one.

the rear bobstay
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Old 18-03-2017, 09:58   #22
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Re: anyone have a boomkin and any advice on building one.

the dreaded rear bobstay...that was simple enough.
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Old 18-03-2017, 11:24   #23
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Re: anyone have a boomkin and any advice on building one.

OK, so you're set on a SS pipe boomkin. Onlinemetals.com has 316L SS pipe in schedule 40 and 80 as well as any other metals you might need. I have nothing to do with them other than a customer.
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Old 18-03-2017, 17:30   #24
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Re: Anyone have a boomkin and any advice on building one.

Yes I've been eyeing up onlinemetals thank you I can't seem to find any that is other the mill finished though I'm starting to think polishing it would a bigger pita then the whole fabrication.
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Old 19-03-2017, 08:54   #25
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Re: Anyone have a boomkin and any advice on building one.

I will go back to your earlier statement about chainplates almost pulling out of the deck. If your chainplates are pulling out of the deck of a 24 foot boat, you have enough structural issues to be concerned with that the boomkin may be incidental. That can almost only come from poor design or more likely poor building quality. The designer of your boat has a good reputation, so your statements only lead to the question of build quality, and I dont mean how pretty it is. I would again urge you to have a professional look over the actual build quality for THE INTENDED PURPOSE OF THE BOAT. You are talking about spending large sums of money to make your boat safe, but you may very well be spending money on a boat the is fundamentally unfit for open ocean sailing. I dont mean to insult you or your boat, but chainplates pulling out of a deck should raise huge red flags about the overall build of the boat. The money spent with a carefully chosen surveyor might save you lots of grief. As with all things on CF, this is just my 2 cents worth. Grant.
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Old 19-03-2017, 09:53   #26
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Re: Anyone have a boomkin and any advice on building one.

I hear you ,and by no means is any insult taken. I'm thinking the 150 genoa added a little extra stresses. When I say pulling through, I mean they're spider cracking and flexing. I had her up for sale and some one did bring a surveyor out to check out the boat. And he seemed pretty amazed with how "stout" the boat was. He had mentioned the cape dorys and some other boats had the same issues and design with the chain plates. Kinda off topic but as far as seaworthy characteristics I can't seem to find a boat with as much ballast/length. The Allegra,Dana, contessa, etc and boats on the "heavy proven" list. My ballast is 3700lbs and displacement is 7000lbs. I Know there's so much more to the equation but at what point in your opinion would you think is too heavy? I'm very green at the helm but we'll read, any real world opinions out there?
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Old 19-03-2017, 09:54   #27
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Re: Anyone have a boomkin and any advice on building one.

.....hahaha should have gotten that Alberg...
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Old 19-03-2017, 10:02   #28
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Re: Anyone have a boomkin and any advice on building one.

Have you considered if you need a boomkin at all?
What is the condition of your mainsail?
Do you plan to replace it? A minor amount of less roach and the boomkin may not be required. Actually it may not be required as is.
Hard to tell from your pics; some of the Eastward Ho pics have a bowsprit too and some don't.
How does the boat sail now?
Where is your mainsheet traveler on deck? Cant see it.
Would a few feet less be easier for moorage and less $ or not?
If you split your back stay with no boomkin, would that be enough? (each stay to the aft outside corner of the stern.
So many questions....
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Old 19-03-2017, 10:26   #29
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Re: Anyone have a boomkin and any advice on building one.

My boom extends to the stern, and my backstay is on my boomkin ,so my mainsail clears my backstay. So without reducing sail area ( which I can't afford) I assume the boomkin has to stay. I've never considered a split back stay, I don't know if that would let the boom clear or not, I'll have to look into that option. The back stay being aft the extra 2 1/2' I assume would give me a better angle and increase the strength (for lack of a better explanation). I don't have a traveler I have a (please forgive me for the lack of terminology) block set up its a 3:1? the tackle is mounted on the boomkin just aft of the stern. I'll see if I have a pic showing this. And I don't have a sprit. I brought that topic up here a while back and we came to the conclusion that since the sails are balanced well and sails good now that in my limited experience moving my headsail foreword I might disrupt sailing ability negatively. I decided I'll be adding a Solent stay. If I did add the sprit I would only do so if it would improve speed ( not sure of this) rather then try to improve balance, since I feel she's ballanced well.....well that's a whole lot....thanks for letting me share haha.
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Old 19-03-2017, 10:46   #30
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Re: Anyone have a boomkin and any advice on building one.

The drawings on some show a much shorter boomkin is why I wondered. It was just a thought.
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