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View Full Version : Kick up rudders and control lines .



PeterSibley
01-21-2014, 02:03 AM
Another quick question if I may. Next in line is a rudder and Mr Fisher of Selway Fisher hasn't detailed a kick up option for my JIM. I could ask him but frankly it's more fun to ask here |:).

I have a few photos in my files showing the geometry of the pivoting lower section but nothing showing the run of the lift and hold down lines and their associated sheaves. Now I'm sure I could work this out for myself but I think it is probably better to benefit from the accumulated wisdom on this board .

Could you show me how you have done it ?

jim_cricket
01-21-2014, 08:29 AM
Mouse's rudder cassette core halves, before gluing together. The downhaul runs up through the gudgeons and around the sheave, then out.

http://jimluton.com/images/rudcore3_web.jpg

http://jimluton.com/images/ruduphaul_web.jpg

The uphaul goes up through this sheave and through a tunnel then out the front.

http://jimluton.com/images/rudpin_web.jpg

The sheaves and gudgeons are held by brass pins through the whole business.

Cricket

Thorne
01-21-2014, 09:09 AM
Not to be unhelpful but I prefer lead weight and a simple uphaul -- much less to fiddle with when hitting a snag or sailing onto a beach in brisk winds...

That said, consider Dyneema or other non-wearing line for this purpose, great stuff with zero stretch.

http://www.luckhardt.com/finishedblade1.jpg http://www.luckhardt.com/finishedcheek1.jpg http://www.luckhardt.com/kickup-full1.jpg

Hwyl
01-21-2014, 09:37 AM
There is a clever way of arranging the clam cleat used by Lasers. I've tried describing it before but seem to get tongue tied. The purpose is to let th clam cleat hold the line in all normal sailing conditions, but release it on a grounding.

If you think of the clam cleat as a series of "V",s you drill a hole at the bottom of the "V's" parallel to the base. The hole is a larger diameter than the downhaul diameter. Normally the downhaul is held in what is left of the "V's" but under extreme pressure as in a grounding, the rope is compressed enough to squeeze past the "V" and into the drilled hole, thus saving your rudder blade.

kenjamin
01-21-2014, 09:43 AM
Hey Peter,

I took the standard SCAMP kick-up rudder and loaded the downhaul tension with a bungee cord.

http://www.bodaciousboats.com/Pin1.jpg

As you can see, there are several extra attachment points for the end of the bungee so you can adjust the tension. What this setup provides is a one line operation of the kick-up function. The uphaul will raise the rudder completely up even with the bungee on the strongest setting. Uncleat the uphaul and the tension in the bungee fully deploys the rudder. It will automatically kick up if it hits anything and then redeploy without anything needing to be done by the helmsman. I have more pictures and more text if you're interested at http://smallcraftadvisor.com/message-board2/viewtopic.php?f=3&t=689

The only problem I've had with it so far is forgetting to move the bungee to its lightest tension setting for storage. If you keep it on its strongest setting when the boat is stored, it will tend to stretch out the bungee. Also if you leave it on the storage setting, it's a bear to move it to a stronger setting while underway from inside the boat — but doable.

akitchen
01-21-2014, 12:34 PM
Downhaul passes through neck to attach to top of leading edge of rudder. Rudder pivots on outer rivet of lower pintle.
Blue dot hides a small quantity of lead.

Andrew

http://i1375.photobucket.com/albums/ag447/andrewtkitchen/RudderDetail_zps480d5755.jpg (http://s1375.photobucket.com/user/andrewtkitchen/media/RudderDetail_zps480d5755.jpg.html)

jim_cricket
01-21-2014, 02:05 PM
Thorne, I used Maffioli Swiftcord for my rudder controls. Very low stretch, soft hand. Not as slippery as dyneema. Techier than it needs to be.
The Laser set up only has a downhaul, which cleats to the tiller. Lasers don't spend much time on a beach, or sailing with the rudder kicked half way up. I think Mr. Sibley is using a remote tiller, and probably needs control lines led to the deck rather than to a tiller.
Cricket
edited to add... Kenjamin, I like the shock corded downhaul. Good shock absorber if you hit something.

Hwyl
01-21-2014, 02:59 PM
There is a clever way of arranging the clam cleat used by Lasers. I've tried describing it before but seem to get tongue tied. The purpose is to let th clam cleat hold the line in all normal sailing conditions, but release it on a grounding.

.



The Laser set up only has a downhaul, which cleats to the tiller. Lasers don't spend much time on a beach, or sailing with the rudder kicked half way up. I think Mr. Sibley is using a remote tiller, and probably needs control lines led to the deck rather than to a tiller.
Cricket



I failed to get my idea over then.

Tom Robb
01-21-2014, 04:23 PM
Gareth, once the line has yanked down into the drilled out clam cleat, how handy is it to get out to where you can re-cleat?

PeterSibley
01-21-2014, 04:45 PM
As usual gentlemen you have proven extremely helpful, thank you all. I'll now try to to work out which of these excellent ideas best suits JIM.

Mike V.
01-21-2014, 04:46 PM
Rather than drilling out a clam cleat you could use a purpose made auto-release clam cleat. I use one on my leeboard downhaul and it works great. The release force can be adjusted and it is easy to reset if the board kicks up. Duckworks sells them, http://www.duckworksbbs.com/hardware/cleats/sd002570/index.htm

John Meachen
01-21-2014, 05:36 PM
I have often posted here on the desirability of a CL257 to hold a rudder down.This is a scheme of a type of rudder stock that works and can be adapted to suit differing transom geometry-obviously there is a cheek omitted.

http://i578.photobucket.com/albums/ss226/John_Meachen/liftingrudderparts_zps88d8ad26.jpg

It is quite important to include a central packer that will allow a substantial fastening for the lower gudgeon to be used and not to take the rudder blade to the forward edge of the stock in this region.The other fastenings in the gudgeon strap may be a bit shorter as they need to be kept clear of the swinging rudder blade for obvious reasons.

dktyson
01-21-2014, 05:49 PM
Are other folks not seeing all the pictures or is it just me? I can only see the pictures posted by Thorne.

Hwyl
01-21-2014, 07:25 PM
I see them

dktyson
01-21-2014, 07:39 PM
I see them now. Must not have had enough faith.

PeterSibley
01-21-2014, 07:54 PM
I see them now. Must not have had enough faith.

:D:D

David G
01-21-2014, 08:00 PM
I'm rather partial the a cassette rudder - held in place with shock cord. A bump, and the blade pivots back out of the way, but the shock cord pulls it right back down afterward... and you can easily adjust the depth of projection by sliding the blade straight up or down... and it'll stay via the shock cord pressure...

Hwyl
01-21-2014, 10:20 PM
Gareth, once the line has yanked down into the drilled out clam cleat, how handy is it to get out to where you can re-cleat?
Relatively easy, geometry is on your side.

James McMullen
01-21-2014, 11:27 PM
Peter, I've run my lines and turning sheaves routed internally so there is nothing trailing, ready to snag on a dock corner, or catch seaweed, no possibility of tangles, nothing that can jump out of place or jam.

I think a cassette type dagger rudder is sub-optimal for a sea boat. You don't want nothing that remains in place only so long as the shock cord stays tight and doesn't chafe through. That's a fair-weather daysailer's trick. A sturdy pivot bolt is what I want instead.

David G
01-21-2014, 11:55 PM
Peter, I've run my lines and turning sheaves routed internally so there is nothing trailing, ready to snag on a dock corner, or catch seaweed, no possibility of tangles, nothing that can jump out of place or jam.

I think a cassette type dagger rudder is sub-optimal for a sea boat. You don't want nothing that remains in place only so long as the shock cord stays tight and doesn't chafe through. That's a fair-weather daysailer's trick. A sturdy pivot bolt is what I want instead.

You're right. I've lost track of what boat Peter is abuildin'. For some reason, when I hear Selway-Fisher... I think of little boats, though I know they have a range of boats. What design is he working on?

PeterSibley
01-22-2014, 04:12 AM
Hi David, I'm building a Selway Fisher JIM.http://www.selway-fisher.com/DoubleEs.htm
http://www.selway-fisher.com/Jimd1.gif
An 18 footer of approximately the same dimensions as the IO boats of the same size . Here's a photo of the current build.

http://pic40.picturetrail.com/VOL282/9443996/24163537/408391572.jpg

skuthorp
01-22-2014, 04:53 AM
Because of our excessively shallow water at low tide, sometimes I come home on just a few inches, I built a rudder with a long narrow trailing blade for my sailing canoe. Similar to a Fireball rudder.
http://i.ebayimg.com/t/DINGHY-SPARES-Rudder-Tiller-Tiller-extension-ex-Fireball-USED-/00/s/MTIwN1gxNjAw/z/l2oAAOxyqOxRwdYD/%24(KGrHqRHJDgFG8r)U5)zBRwdYCunc!~~60_35.JPG
But over the last month I have built one more or less as the plans, larger and deeper. It'll depend where I'm sailing I reckon. More or less like this,
http://www.glen-l.com/weblettr/webletters-1/wl5kikup2.jpg

Wooden Boat Fittings
01-22-2014, 07:03 AM
Kareela's rudder is in two parts, similar to Jeff's (although Kareela is a kayak, not a dinghy). The lower section is held down with internal shockcord, which allows it to pop up if it strikes the bottom but be pulled down again when the water depth is sufficient, just as David G outlines. (The rudder blade is thus protected even if the shockcord is damaged or worn.) On beaching or launching, the shockcord can be overridden if desired by a separate control line leading to the trailing edge of the blade, which is cleated off on the cockpit coaming.

Mike

Adles
01-22-2014, 07:48 AM
Also, Duckworks carries those auto-release cam cleats that let the rudder pop up if you hit something. I think this is more elegant than shock cord.

http://www.duckworksbbs.com/hardware/cleats/sd002570/index.htm

jim_cricket
01-22-2014, 08:53 AM
I failed to get my idea over then.

I grok your point now. About the cleat, not the set up. Sorry.

PeterSibley
01-24-2014, 06:40 PM
Also, Duckworks carries those auto-release cam cleats that let the rudder pop up if you hit something. I think this is more elegant than shock cord.

http://www.duckworksbbs.com/hardware/cleats/sd002570/index.htm

Thank you , I just ordered one. No shock cord.

http://www.duckworksbbs.com/hardware/cleats/sd002570/GroupAutoRel.jpg

+
http://i578.photobucket.com/albums/ss226/John_Meachen/liftingrudderparts_zps88d8ad26.jpg