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I have seen tons of photos and videos of various types of rigs on different types of boats, but unlike the junk rig Bible - Practical Junk Rig - I have yet to find anything that exists for the oldest known sailing rig, the Crab Claw. In fact, I have yet to find any "How to" articles for designing your own crab claw rig.

Anyone have any resources or ideas?

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http://tamamoana.blogspot.com/search?updated-max=2007-09-03T10:23:0...

Some interesting reading further down on experimenting with the cc rig.

Thanks for the link.

I am also (seriously) considering using wishbone masts. I think there are more advantages to this than disadvantages. Wishbone masts will allow the sails to freely rotate. I would need to put a control line on the tack in order to keep it in a stable position, but could dictate that position. By easing the tack control line, I could also quickly move the sails from a "spars up" position, to "spars down" position when needed, with the ability to pull the tack to windward or leeward as necessary.

The added advantage would be redundancy of masts. If something broke, I could modify the rig to single masts until repairs could be made. Will it work? Who knows (Except maybe Gene Perry who did it with carbon fiber masts and spars on his Tiki 26, but I have not heard from him in years.)

Here's some performance data from a 13m2 crab claw (Wharram design) with Tonkin bamboo spars (now 4 years old, but with epoxy and paint coating in the Pacific Northwest) on a Tiki 21 --

http://econscience.org/tiki/2015/02/15/performance-of-a-bamboo-poly...

We're trying this sail on a Hitia 17' now but want to get better upwind performance, especially in light wind.  Thinking about windsurfer masts or building top antenna mast sections as spars inside sleeves along foot and luff.  Maybe you could get these in Texas?  Put two 4.8m windsurfer masts end to end with a section of the antenna stuff and you could get 36' with most strength in the middle where halyards/sheets attach and flexibility at the outer tips.

I've been pretty happy with bamboo (~9m Tonkin spars), but have broken and reinforced it.  Still need to try some solid wood or laminated ones (as Hans did for Wakataitea, Klaar did on Ontong Java, and Kiko does in his Hawaiian sprits'ls)...

There is a LOT to optimize in the design and construction of crab claw rigs (and I look forward to a full-on manual), but for now here are my best efforts to lend a hand:

http://econscience.org/tiki/2015/02/15/performance-of-a-bamboo-poly...

http://econscience.org/tiki/2011/04/26/prepping-spars-for-the-big-c...

http://econscience.org/tiki/2011/05/11/rigging-the-13-m2-crab-claw/

http://econscience.org/tiki/2016/05/04/crab-claw-sails-the-mast-to-...

And here's a fledgling attempt at measuring sail dimensions and attachment positions in extant crab claw rigs:

https://docs.google.com/spreadsheets/d/1FHmZAbkyklk6xGKQklI8qAoeJor...

Re alternative masts and the crab claw, Thomas and I had similar thoughts and constructed an A-frame mast on our Hitia 17 with ~13m^2 crab claw (later ~20m^2).  You can see photos of it along with performance data here --

http://www.searunners.net/18-hour-trial-on-lake-wa-nighttime-circum...

Budget Boater said:

Thanks for the link.

I am also (seriously) considering using wishbone masts. I think there are more advantages to this than disadvantages. Wishbone masts will allow the sails to freely rotate. I would need to put a control line on the tack in order to keep it in a stable position, but could dictate that position. By easing the tack control line, I could also quickly move the sails from a "spars up" position, to "spars down" position when needed, with the ability to pull the tack to windward or leeward as necessary.

The added advantage would be redundancy of masts. If something broke, I could modify the rig to single masts until repairs could be made. Will it work? Who knows (Except maybe Gene Perry who did it with carbon fiber masts and spars on his Tiki 26, but I have not heard from him in years.)

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