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cybuilder
07-11-2012, 04:14 PM
Here's a good newbie question for y'all: Skene chocks come in port and starboard? Which is which? I did a Google image search and got no consensus.

http://www.tanzer22.bravehost.com/ about a quarter way down this page are photos of two different pairs of skene chocks mounted at different positions on the bow of the same boat - and they are not oriented the same. There has to be some logic to this, I just don't understand it for lack of experience.

I have a double-ender and will be mounting a pair at each end. Which way should they go? A picture is definitely worth a thousand words in this case.

Peerie Maa
07-11-2012, 04:54 PM
It seems to me that the direction of the dock line should run across the gap, not parallel to it.
http://img.nauticexpo.com/images_ne/photo-m2/sailboats-warping-fairleads-232744.jpg
So these would be fitted forward, with the top of the image aft, so the dock line runs across the slot.

Personally I prefer this design with the outboard lip.
http://www.classicmarine.co.uk/boatstore/uploads/images_versions/3242.jpg

James McMullen
07-11-2012, 06:50 PM
The whole point of these doohickeys is to allow you put the rope in the chock from the top when the rope is totally loose, yet will keep it from jumping out and doing violence to your caprail varnish when a wake or something causes your boat to surge at the dock. Mount them so that those fingers will do the best job of keeping the rope in place when the docklines are led at their typical working angle, whatever that may be. Depending on how far forward or aft you mount them and how much flare your boat has, that might be one way or the other. Just mount them so they work the best at doing what they're supposed to do.

Breakaway
07-11-2012, 08:47 PM
From experience, I will say that if you are at a fixed dock and the boat falls below the level of the dock cleats at low tide, that reaving the lines through chocks like these creates a lot of chafe as the line tends to wear around the "points" of the slots; they work great when docklines are led down to the dock from the boat. Also work well to keep an anchor rode from sweeping the bow while your on the hook.

That's my experience.

kevin

MiddleAgesMan
07-11-2012, 09:53 PM
If we're talking about a small boat then use at the dock is probably irrelevant. I placed the ones on my Simmons Sea Skiff with anchoring in mind. Properly positioned for anchoring you have to bend the line about 90 degrees to drop it in the chock. Once there the fingers will keep it there when the bow lifts and falls.

The ones I bought have leads under the fingers that tell you which way they are to be mounted. Forget the way the "fingers" are pointed for a minute and look at the shape of the chock below the fingers. Mount them in such a way as to minimize chafe for an anchor rode or dock line that leads forward.

nedL
07-12-2012, 08:05 AM
The ones on the stemhead of that Tanzer are definately wrong. the ones adjacent to the foredeck cleat are mounted correctly for the use they are seeing in the photo, but are 'backward' from a normal orientation if they were farther forward. As MiddleAgesMan said, the intent is to reduce/eliminate chaffing, so you want them mounted in such a way that the line doesn't rub on the internal 'corners' as it leads forward. In the photo of the two chocks in the second reply, a boat's stem would be between the chocks with the boat / stem facing up in the picture.
Chocks should never see strain, either up or sideways, they are simply 'fairleads' to reduce wear & chaffing on a line or the toerail in the location that a line would naturally lay. If a line is making a noticable turn as it passes through a chock (in any directionother than down - as to an anchor) it should NOT be running through a chock.

nedL
07-12-2012, 08:46 AM
This is a very real example of what can happen when lines are led through chocks with a noticable angle change as they pass through the chock. Chocks are fastened with only 'small' wood screw, so if the boat is bouncing around the chocks can get ripped out of the toerail (or deck), leaving rough edges that will chew right through the lines. (This case was a hurricane.)

(edit to add - in this case it was a painful 'learning experience' for my parents of when not to lay your docklines in the chocks. She was properly rebuilt with no short planks & lived on for close to another 25 years, 9 of them with our family.)

http://im1.shutterfly.com/media/47b8df10b3127ccec36bcdaa812d00000010O02Bbs3DVuzZA9 vPhI/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/

cybuilder
07-12-2012, 10:37 AM
Excellent feedback, all. I understand the logic now. I now see how the shape of the lead corners under the fingers indicate which way they should be mounted to minimize chafe relative the angle of the dock line. I also see the importance of minimizing any turn of the line through the chock, so the chock takes minimal strain. Both of these depend on the placement of the deck cleat securing the dock line and the angle of the sheer at the chock. The chock are going on today with confidence. Thanks, all.