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These comments are my own thoughts and some may prefer to simply dismiss them. That's OK, it's a big ocean. We built a pair of Tiki 8ms for a resort hotel here in south FL. They go out as 6-pack charters 3 times a day 7 days a week. They usually pick up and prop off guests right off the beach in front of the hotel. But many days the beach surf will be high enough that they will take the guests by van to the marina and load and unload there. This maens that they have a fair amount of manouvering to do in restricted areas. Part of the my agrrement with the operators was that the boats must manouver well in reverse under power.
 If one mounts the outboard aft  it is possible to steer the motor as well as use the rudders for better control. Mounting the motor aft also means that the prop will come out of the water more often. On these particular boats they also wanted an extra aft cockpit for the captain where all of the sheets and motor controls would be at hand. This put the motor under a box/table in the aft part of the cockpit.It also causes the boat to trim stern down until the guests board and then she trims evenly. The favored seating is the front tramp and the fwd beam. This aft cockpit required shortening the tillers by 2' which increased the helm loading to an unacceptable level.
  To solve these issues we changed the sternpost angle from 25 to 5 degrees. On a glass boat this is easy to do. With the rudder shaft at a 25 degree angle about 25% of the effort the rudder exerts is to drive the stern down as opposed to turning the boat. This increases the helm loading. We aslo built the hulls without the skegs. This eliminates the protection for the rudder and required us to build kick-up rudders so that when the boats are beached, intentionally or otherwise damage to the rudder is avoided.
  Removing the skeg and changing the rudder shaft angle allowed us to fabricate rudders with counter balanced blade areas. This effectively reduces the rudder load to a desirable level. Not simple to ciper out and execute at all. We went through 4 generations of rudder blades before getting it dialed in. The first shot at the tillers resulted in complete failure and beefier tiilers were designed and built. The rudder loads are intense when motoring in reverse and the rudder grabs and wants to slam to one side.
  The results after a year in service of these two boats is very good. The boats are very manouverable . The lack of a skeg  and the increased rudder area  makes them  turn much easier. They still track nicely and don't wander. The boats also tack much easier. There is no need to back the jib at all.
One benefit of the kick-up rudders and no skeg that we did not foresee was thaat they are much easier to un-grounf. When the boat goes agound with a skeg it is coomon for the skegs and rudder bottoms to catch on the sea bottom and resist efforts to back off or turn to kedge off. The waters around this part of the world are skinny in many places and grounding is not uncommon.Without the skegs it is nuch easier to lift the rudders and shift crew weight to the front of the boat andreverse off. I find that even when soloon the boat that engaging the motor in revers and moving to the bow and bouncing up and down that the boat will shimmy its way back off.
  Again these are just may thoughts and observations. The kick-up rudders are certainly not as simple as a barn door style rudder.  However I have been very impressed with performance of the straightened stern post/rudder shaft and the elimination of the skeg.


 

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Considering the finite area of operation and usage of the boats, I see no problems with the modifications, and they have obviously proved beneficial for the intended purposes.

Having built, sailed, lived on, cruised, beached, and run hard aground in a Tiki 30, I can honestly say that such modifications may not be suitable for a cruiser. We cruised extensively in Florida and the Bahamas in our Tiki 30 and regularly intentionally beached it. We had two toddlers at the time and beaching was the simplest way to embark disembark on the wonderful beaches.

That being said, we never had a problem backing off the beach or kedging off, and we did not experience any problems operating in reverse or have any need to back the jib while tacking to windward. However, we also did not have a stern cockpit or any need to shorten the standard tillers, which seem to be the driving force behind the modifications you made for your client.

On our last day of sailing ownership of our Tiki 30, we ran hard aground on rocks in lake Okeechobee when we strayed from the channel. The keels and skegs did their jobs perfectly and we even backed over rocks when attempting to relieve ourselves from our embarrassing situation. When we hauled later that day, there was little sign of our encounter with the rocks. Our starboard keel had a nick in the fiberglass about the size of a quarter and some bottom paint was rubbed away on the keel and skeg. Our Tiki 30 was no worse for wear.

It is obvious that your design changes are exceptional for the boat's intended usage and would be a worthwhile mod. You may want to look into finding some more clients for such a boat in the Florida Keys, especially Marathon and Key West where gulf side day charters, reef trips, and sunset cruises for a 6-pack boat are always growing.

As for the typical Wharramite sailor, the keel and skeg are, in my opinion, a very important requirement for cruising.

Just my .002 (2¢ adjusted for inflation)
to both of you guys i must thank you both for the time and effort you put into your posts,without blowing too much smoke into your nether regions,i find them always informative and backed up with hard gained experience,keep it coming.

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