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Catalina/Capri 25/250 Sailor's Forums

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Custom Machined Spinnaker Crane

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Frank Hopper
Past Commodore

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Pitcairn Island
6776 Posts

Initially Posted - 12/16/2005 : 03:02:25

Following on from another thread regarding custom machining for our boats...
The current National Champion invented and manufactured this for his spinnaker halyard. As part of the installation you must convert to internal halyards which is a valuable and easy conversion. I am trying to convince him that some of you would make it worth his time to build some more. Would you want one like this?
(Duane, there is no issue with class rules for Nationals here is there?)
[url="http://homepage.mac.com/fhopper/PhotoAlbum123.html"]more picts here[/url]

Edited by - Frank Hopper on 12/17/2005 07:17:08

Buzz Maring
Master Marine Consultant

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USA
1768 Posts

Response Posted - 12/16/2005 : 08:37:54

Hi Frank,

That spinnaker crane really looks nice! Do you have any idea what he might charge for it?

Frank ... when do you sleep?

(edited for spelling

)

Edited by - Buzz Maring on 12/16/2005 09:20:31

djn
Master Marine Consultant

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USA
1561 Posts

Response Posted - 12/16/2005 : 10:03:07

Hi Frank, this is the one I am having made up. This picture is from Bob Nichols "Masthead Crane" in the tech tips. Cheers.

Edited by - on

Frank Hopper
Past Commodore

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Pitcairn Island
6776 Posts

Response Posted - 12/16/2005 : 11:12:05

This is obviously a very sophisticated solution to an ongoing problem. We have just begun to talk about it. I believe he also machined the sheeves, it takes three. The mast exit plate could be included or not. I wonder if he could do it for $130.

Edited by - Frank Hopper on 12/17/2005 07:17:43

djn
Master Marine Consultant

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USA
1561 Posts

Response Posted - 12/16/2005 : 11:45:33

Hi Frank, I like your solution better. Is it just the attachment that is bolted to the end of the masthead or a whole new mast head. I like the idea of bringing the lines inside the mast. It appears that all three lines would go in the mast....is that correct? Is there any downside to running the lines through the mast? Also, when I called CD about a crain, they said that the mastheads for the SR and TR are different. Which one is this crain made for? Cheers.

Edited by - on

Champipple
Master Marine Consultant

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USA
6855 Posts

Response Posted - 12/16/2005 : 12:46:58

At this time, there aren’t any class rules regarding a spinnaker crane. Though one isn’t needed, it is beneficial and provides for better sail shape, better hoists and better performance.

If we were to consider a crane rule, it would probably go something like this –

The turning axis of a spinnaker halyard block or the point of attachment of a fairlead or other hardware intended for moving the spinnaker halyard forward of the mast whether attached to the masthead or masthead a crane must not extend from the factory original forward most masthead pin a distance greater than XXX inches. This measurement is taken with the block fully extended at an angle 90 degrees, or as close to 90 degrees as possible, to the mast itself.

Edited by - on

Frank Hopper
Past Commodore

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Pitcairn Island
6776 Posts

Response Posted - 12/16/2005 : 14:26:04

This is a standard rig crane which uses the stock pin locations. He would have no problem creating a TR model or 250 models for that matter. Yes going internal is pretty much all or nothing. My boat came with internal halyards from the factory, They have enough advantages that few would turn them down given the choice.

Edited by - Frank Hopper on 12/16/2005 14:31:13

djn
Master Marine Consultant

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USA
1561 Posts

Response Posted - 12/16/2005 : 14:56:18

Hi Frank, is the masthead the same one used to go internal? If it is the same masthead, what else do I need to put the lines inside the mast? Also, is the crane made from fiberglass or metal. I can not tell from the pics. Cheers.

Edited by - on

atgep
Master Marine Consultant

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1009 Posts

Response Posted - 12/16/2005 : 20:18:35

I made my own out of 1/8" stainless stock. It is not fancy and I can find no easy way to get the halyard into the mast. I tie the spin halyard to the bow pulpit.

I has held up to a hundred miles or so with the spinnaker up. I has never fouled the furler. That was the main goal.

Better pics can be found at

http://www.freewebs.com/atgep

Tom.

Edited by - atgep on 12/16/2005 20:19:30

dlucier
Master Marine Consultant

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Virgin Islands (United Kingdom)
7583 Posts

Response Posted - 12/16/2005 : 21:32:52

"Would you want one like this?" -Frank

No...This custom crane wouldn't work with my Harken furling because it would leave the spinnaker halyard too close to the upper swivel. The crane I have moves the halyard out probably a good 6-7 inches (counting the spinnaker block) from the front of the masthead so as to prevent fouling the swivel.

Here is a pic of CD's C22 crane. I wonder if it could be modified to fit a C25 masthead?

Edited by - on

atgep
Master Marine Consultant

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1009 Posts

Response Posted - 12/16/2005 : 21:52:47

I have the harken furler as well. The LAST thing I ever want, it to have the upper swivel fouled. The way I set my crane up. Keeps the spinnaker gear 4-5 inches from the upper swivel on the furler. I made mine after coming up empty handed trying to convince anyone local to weld one for me. (too small of a job).

Tom.

Edited by - on

Frank Hopper
Past Commodore

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Pitcairn Island
6776 Posts

Response Posted - 12/16/2005 : 22:03:13

I believe you ae all speaking to the strength of my friend's design. There is no block waging around up there.

Edited by - on

dlucier
Master Marine Consultant

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Virgin Islands (United Kingdom)
7583 Posts

Response Posted - 12/16/2005 : 22:09:45

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by fhopper@mac.com
 I believe you ae all speaking to the strength of my friend's design. There is no block waging around up there.
<hr height="1" noshade id="quote"></blockquote id="quote">

It wasn't the block that was causing my problem with the upper swivel, just the proximity of spinnaker halyard itself.

Edited by - dlucier on 12/17/2005 00:40:58

djn
Master Marine Consultant

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USA
1561 Posts

Response Posted - 12/16/2005 : 23:24:36

Hi Frank, that is what I like about your design, it is very clean. As soon as I find out what rig I have, Standard or Tall, I'll let you know so you can put me down for one. Cheers.

Edited by - on

aeckhart
Master Marine Consultant

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USA
1709 Posts

Response Posted - 12/17/2005 : 11:45:55

Frank,

I like the design you've shown, particularly since I am interested in running the halyard through the mast. I would be very interested provided it was offered with appropriate sheeves and pins.

Edited by - on

dlucier
Master Marine Consultant

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Virgin Islands (United Kingdom)
7583 Posts

Response Posted - 12/17/2005 : 12:51:41

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Duane Wolff
 At this time, there aren’t any class rules regarding a spinnaker crane. Though one isn’t needed, it is beneficial and provides for better sail shape, better hoists and better performance.<hr height="1" noshade id="quote"></blockquote id="quote">How so?

Edited by - dlucier on 12/17/2005 13:44:11

Frank Hopper
Past Commodore

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Pitcairn Island
6776 Posts

Response Posted - 12/17/2005 : 13:30:04

He meant the crane, not the rule.

Edited by - Frank Hopper on 12/17/2005 13:56:06

Champipple
Master Marine Consultant

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USA
6855 Posts

Response Posted - 12/18/2005 : 21:04:27

Moving the head attachment forward on a fixed peice of hardware can do a number of things.

First, it keeps the halyard out of the way of the forestay and jib halyard or furling equipment. This can help eliminate a huge factor that could get in the way on both hoists and douses.

Secondly, Tri-Radial racing spinakers have a Higher center of effort than an asym. Moving the head forward even an inch allow for the sail to fill even more getting the kite out in front of the boat is key to maximize performance. I'm going to steal a bit from Steve Colgate's book to try an explain this. Spinnakers in general have a sail shape built into them when they are sewn. If you were to take a tri-radial or symetrical spinnaker and give a clew to 2 people and the head to a third and have them pull their end of the sail taught, the remaining sag is the shape that is already in place. If the person holding the head were to take one step toward the other two people there is additional shape that can be noticed in the sail. While its not the same direction that a spinaker crane would move things, it is conceptually very similar. The crane allows the sail to fill out in front of the boat.

Your also allowing for greater separation from any turbulent air coming off the main. When your way up top, where a lot of the physics of sailing is taking place, inches here and ounces there make huge differences. In this case moving the head forward an inch allows a bunch of square feet to get fresh breeze only a few feet down.

Edited by - on

dlucier
Master Marine Consultant

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Virgin Islands (United Kingdom)
7583 Posts

Response Posted - 12/19/2005 : 08:54:40

Thanks Duane,

I built my crane to get the spinnaker block out and over the forestay as far as possible so as to avoid fouling the furling swivel and to give my bunched up chute scoop as much room as possible...It's nice to know that I may have increased performance to boot.

(On a side note...During a cruise to the North Channel last year, one of my sailing buddies had a mishap on his boat. While sailing along enjoying the day, his forestay snapped at the masthead, dropping his genoa and furler over the side. He said the only thing that prevented the mast from joining him in the cockpit was the spinnaker halyard that was attached to the bow pulpit.)

Edited by - dlucier on 12/19/2005 09:10:12

Champipple
Master Marine Consultant

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USA
6855 Posts

Response Posted - 12/19/2005 : 11:14:34

I believe it Don. If his main was up, that probably helped too. I usually make sure the halyards on our boat can run from the bow cleat to the stern rail. In a pinch between the spin pole lift, boom lift and the 3 halyards, I figure I can hold that guy up for a short motor.

Edited by - on

SJ
Navigator

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USA
198 Posts

Response Posted - 12/20/2005 : 12:38:18

What I have on mine is, the halyard is run internal and exits the top of the mast approx 12 inches below the masthead, on an angle forward. The crane I have actually moves the block out about three inches and up about two inches. Very similar to the one for the 22 but imagine it being lifted as well. The halyard also exits the mast approx 7 feet above the deck so that it can be jumped if necessary, that is when my son is on board and I'm not single handing....

Edited by - on

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