Pictures of the AHPC rudderstock.

[color:"red"]Everybody please note that when two rudderstocks look the same they can still behave totally differently. [/color] The whole trick to the Rod lock down system is in the details. Get those wrong (as McKenzie did) and you end up with a poor rudderstock. Get these details right and you'll end up with an excellent rudderstock.

Also note that in my opinion all Mckenzie stocks can be "repaired" to the planned behaviour by replacing the McKenzie rod system by the AHPC rod system. It is all in the details of how the rod system is implemented. The McKenzie rudderboards and the carbon stock itself are good, the McKenzie rod system and lock-down plates are just wrong.

I think this modification is by far the cheapest to perform. Buy two rods with additional locking plate (goes onto the tiller arm) and much stronger threaded claw (that goes around the rudderboard) will not cost much at all. Shipping of these parts will not be dear as all components will fit inside a plain envelopped used for letter sized documents. You will have to do some TLC work to fit the new rod but even that is not beyond most sailors capabilities.

Now I will present the pictures and give some additional comments.

I sailed with the McKenzie stocks one and I've tried to get them properly tuned on the beach. I eventually gave up and adviced the owner to spend some money on proper stocks, well worth it. Fine tuning my own AHPC stocks took about 15 minutes for both sides including some 20 kick-up and lock-down tests. That was back in spring time 2005 and I never had to re-adjust it since.

















My additional comments after using this system for almost 2 years now :

First the rod system, note how :

-1- the rod itself is longer than on the Mckenzie stocks. It bends more easily as a result. You don't have to lean over backwards as far.

-2- The fork that is fitted over the protruding bit on the rudder board is much more robust and it will NOT bend when put under high load.

-3- The threading on the rod is of a larger diameter then on the McKenzie system; also a shorter portion of it is exposed. This thread will NOT bend only load. And I have placed it under load plenty of times.

-4- The rod itself is made of glassfibre (NOT carbon), however it is covered with a layer of heat shrink tube. The Heat shrink is actually the black stuff that you see. This heat shrink has two major advantages. You can use a glass rod (bends more easily, as is critical in the operation of the system) without worrying about glass splinters finding their way in your flesh. The heat shrink also prevents the glass rod from being damaged or disintegrating. The heat shrink keeps all fibres in line, preventing fibres to break away. The black also looks better I think.

-5- All fittings on the rod are high grade stainless steel = strong, stiff and very durable. Even the little plate that takes the lock down pin is of high grade stainless steel. This means that its hole will not wear out and neither will the lock down pin itself.

-6- The stainless steel handle on the far left hand side of the rod is a key feature in the operation of the system. If it is too short (as in the Mckenzie case) the lock down system will be hard to engage. In AHPC case the handle is precisely of the right length. More on this later.

-7- The lock down pin in the AHPC system is indeed a PIN and not a plate as in the McKenzie system. This makes engaging the lock down ALOT easier ! The pin itself has a round tip (dome shaped) and this means that the pin will guide itself into the locking hole when positioned close enough to the whole. When the handle is held right then with just one hand the skipper can just place the pin on the plate containing the hole and find the hole WITHOUT LOOKING by just squeeshing the handle to the tiller and wiggling his hand just a little bit. As soon as the pin comes close to the edge of the hole it will drop in immediately. By squeeshing the handle towards the tiller the rod is bend a little and thus when the pin has found its locking hole the whole system is under some mild tension and there is no play in the setup.

-8- The rod comes relatively far forward on the tiller arms and teh skipper only needs to hold the left hand handle to engage the system. Meaning you really don't have the lean that far back on the boat. It seems like the Mastrom system requires you to lean back farther.



There is on other advantage to the AHPC stocks and that is that the rudder heads can be made to jam a little bit in the stocks. This can be adjusted by tightening the bolt that acts as the rotation axis of the baords. When carefully tuned, and this is an one time job as it will not slacken over time, then the locking rod can be disengaged without the board floating up. Or one can just swing the board down and sail away throught the surf and sandbars without wasting time on fully locking down the rudder. Once out the rudder can set properly and locked down fully.

Why is this handy ? Well, my experience is that other stock system allow the rudders to float upwards when the boat picks up speed, making steering in the surf very cumbersome and sluggish. Such horizontal rudders are also great ways to break your hardware. What I do now with the AHPC stocks is that I keep the leeward stock in its up position (out of the water) and as soon as I'm sailing away from the beach I have the locking rod of my luff rudder in my hand. Pressing down every one in a while to feel if the bottom is still there. As soon as I have about 2 or 3 feet of water below my keel line I quickly pull up my luff rudder board and then quickly swing it down again. The momentum of the board will then swing it down almost entirely, here the jamming action will keep my rudder down even when I really speed up the boat, however if I encounter another sandbar then the rudder is easily pushed loose again. Often this is a one-time action and I let go of the rod two have both hands available to work the mainsheet and the tiller to get through the larger surf that is further out. This way I have much improved steering without the need to lock down the system or to keep holding the system/lines/tillers to keep the rudders pressed down. This is something I could never do with my prindle stocks or even with various F18 stocks. I consider this to be a major advantage were I sail.


Disadvantages of the AHPC !

Well, in my opinion there aren't any serious disadvantages. But I will admit to the fact that the Hobie system is easier when you need to clear weeds often. However, the Nacra system or even any lock-down line system is worse then the AHPC stocks. The only line-lock down system that was better was a very special system as designed by Phill Brander himself. But I never seem a comparable system on any other boat, certainly not any production boats. It is also a much more complex system requiring many more parts and a bungee system inside the rear beam.

Disadvantage 2 (and that will be the last one) could be the fact that unlocking the system manually is easy when the skipper graps the rod in the middle and not on the stainless steel handle. You have to bend over the back of the boat a little bit farther. However I really don't see this as a problem as it is still easy to do, it disengages quickly and fully, and I don't know many situations where releasing the system manually is critical. You always have the option to let the system disengage automatically and to chose the time and spot where you want to clear the weed.

In my opinion ; these two disadvantages are rather minor points. It is not that the AHPC is bad in this respect, not at all actually, but rather that some other system is better then the AHPC system in this respect.In all other respects the AHPC is best. I think this is a pretty good score board for the AHPC setup.


For some info on how to properly lock down teh AHPC rod system go here :

http://www.ahpc.com.au/pdf/Using%20Smart%20Lk%20Snap%20System.pdf


I found that the following works best :

-1- Once clear of the beach, sandbars and surf; lift the rudderboard up and clear of the water then quickly push it down under gravity and pushing on the rod with some force. The board will swing all the way down, despite the water resistance. You are holding the end (handle) of the rid with only one hand.

-2- Move the rod down to the tiller with your hand on the handle placing the locking pin roughly on the lockigng plate )containing the locking hole)

-3- Wrap your fingers around the tiller arm while keeping the rod handle inside the palm of your hand. Now squeesh the handle towards the tiller arm, thus bending the locking rod a little.

-4- Move your hand about a little bit when squeeshing so the locking pin finds the locking hole. Let go of the rod and tiller when the pin is in the hole.

-5- When needed press down on the middle of the rod to push out any remaining bend. This will push down the rudderboard to its maximum forward position. When point -1- was done right then this action -5- should not be necessisary.


Disengaging :

-1- Grap the rod in the middle and pull upwards, this bends the rod a little and this is sufficient to have the pin snap out of the locking hole.

-2- throw the rod backwards in teh water over the rudder baord and have the first contact with the ground push the board up (this requires very little contact with the ground so no major risk of damage) or pull the board up by pulling on the rod itself. Of course I have set up my own rudders to jam inside the stock a little bit and so I often just disengage the rod and reach beneath the watersurface to give the board a short push to become unstuck.

-3- When pulling the board clear of the water, pull the rod all the way towards the locking plate for a lifted rudder and squeeh the locking pin as you would when engaging the system.

Wouter