LOCK CROWTHER DESIGN NOTES AS PROMISED

[cat man do]

As promised in a previous post somwhere I have managed to supply Lock Crowthers thought's on multihul design and constuction.

As mine were water damaged, I would like to thank Stuart Bloomfield for supplying these.

He was one of the designers at Crowther Designs, and now runs his own office and I believe can still supply the old stuff as well as his new designs.
http://www.bloomfieldinnovation.com/

Very interesting are his findings on wave induced capsize.

These may have lost some image quality as I got them in 800 kb files and had to reduce them for you to view here.

Enjoy


Dave

Good job on the photos. Completely readable. Interesting article

[cat man do]

Suprised myself they came out that clear.

An important peice of multihull history that should not be lost

[fhrussell]

Great! Thank you!!.......

[Intentional Drifter]

That was good stuff. Thanks, and the scans came out great.

ID

[OldYachtie]

He mentioned balsa soaking up a lot of resin. You can buy pre-coated balsa that has a factory finish that prevents that. (Baltek al-600/10 is the best known example.) Balsa is still a bit heavier than foam if you use the cheaper standard grade, but only about 400 pounds for a 65' boat. It is much cheaper, and much stronger than foam. Balsa/vinylester is used in, for example, J-boats.

[cat man do]

Epoxy thank's, the only resin that sticks to timber succesfully is epoxy, everything else is a compramise on strength.

And then you have the different weights of glass, you will usualy use less glass on timber core than foam, therefore less resin, and I always use less epoxy than I do Vinyl and Poly, so I won't/don't use Poly or Vinyl for anything.

The reason the comments may be out of date is because Lock passed away several years ago while sailing Deguello off the East coast of Australia.

Dave

[rgwla]

Thanks for the notes, "CatManDo". I am restoring a Crowther designed 42' Tri. She was VERY wet when I got her, but well built to start....

[Southern Star]

Thanks Cat - very interesting read.

Brad

[beiland]

Does any one have a photo of Lock Crowther's 40' racing cat called "John West"

How about a photo of his 46' cruising design, "Vehia" or "Odara"

[rustyrusty]

Can I assume a Crowther seafire would be foam deck and maybe below the water how do you find out.

[mrybas]

Here’s my Crowther #150 originally built at Hutchesons in NZ.
I’ve sailed her over 20 knots many times in flat water and consistently sails over 200 mile days. Fantastic boat we have sailed past several larger/newer ‘performance’ cats.
https://www.instagram.com/tv/CcTlSi3...d=YmMyMTA2M2Y=

[GRIT]

Originally Posted by mrybas

Here’s my Crowther #150 originally built at Hutchesons in NZ.
I’ve sailed her over 20 knots many times in flat water and consistently sails over 200 mile days. Fantastic boat we have sailed past several larger/newer ‘performance’ cats.
Attachment 257428 https://www.instagram.com/tv/CcTlSi3...d=YmMyMTA2M2Y=

Sweet ride!

Cheers.
Paul.