A Photo & Discussion Forum for Wharram Design Enthusiasts
On my Pahi 31, in my complete cockpit remodel, I've moved my Yamah8 outboard location from the aft beam to more amidships and mounted it on a 42" V-shaped, pivoting, sled in a well in the cockpit. Wave slap and cavitation were problems in the fixed aft beam location. In experimenting with raise and lower options for the sled, lines and winch work OK, which I would prefer over hydraulics or some mechanical method.
My question: Will gravity be enough to keep the sled in the down position with wave slap or a hard reverse, or do I need to devise something to keep it locked in the down position?
Any thoughts? Thanks,
You must have something to keep the engine down when reversing. Otherwise the engine will tend to lift up and you will not have drive. We usually motorsail with no problem and with nothing to keep the engines down. What we use to keep the engine down is a stick that we jam one end in the sled and there is a bolt sticking out on the top end of the stick that fits into a reinforced hole drilled in the aft bulkhead of our engine compartment. We lift our engine sleds by use of a tackle and when we put the stick in place, we tighten the tackle and the sled lifts and keeps the stick where it belongs. It is easy to do and easy to live with. This method has worked ok for us for 50,000 miles so we like the simplicity of it and its reliability. Ann
Thanks Ann, I was hoping to find someone, like you, with that experience. You've confirmed my suspicions of how it will act and I too prefer something simple.
I had a 6 hp Johnson on a sled under the cockpit of my Pahi 31. I raised it with a simple 2:1 tackle. I had no way to keep it down and I think it was better that way. In rough seas I used to slacken the tackle off once underway. The sled would plane on the wave tops thus not drowning the engine and fall down in the troughs thus minimising cavitating. It was like a suspension system.
I never considered there might be problems with reverse and I never had any although now I see the possibility. This would be more likely I think with a short sled or more powerful motor. My sled was long and weight seemed enough to keep it down.
I went for a fixed pod under the cockpit on my re-build for simplicity. There are pictures on my page. The engine is now just forward of the rear beam which is working well.
Always great to hear of another P 31 sailing.
Galway Bay is right. We also take our sticks out when motoring in rough conditions such as after a stormy time when the wind dies but seas are still high. Our 9.9s needed the stick to keep them from lifting in reverse and also when we replaced the 9.9s with ner 20 hp engines we found that we still need the stick when reversing. We built our sleds to plan and then added a rounded V to the sled bottom to give it a gentler entry. This was a good modification. Ann and Nev
I very rarely used reverse except for pulling off a beach and with my old fixed rear beam mounted brackets I had to remember to lock down the motor. My new sled is 42" long and I don't need to lower much to reach the waterline so I think it will plane well without a "stick".
I looked at your photo's of your Pahi and my motor will be a little bit forward of yours, my prop will be about 24" aft of the center of the boat and at the far starboard side of the cockpit.
I too have eliminated one of my beams when I modified from 14' beam to 16'. Hanneke approved of the elimination of beam #3. I didn't relocate that beam to the center as you did, because I have the wingsail design and my mast is forward between the original beam #1 and #2.
I live in WA state on Puget Sound and there is another Pahi31 with the cutter rig sailling, located in Long Beach WA. We visited each other in person to see each others boats but never had the boats together to compare the two sail plans side by side.
I see also in your photo's that you have the dagger boards. I never had them nor does the other neighboring Pahi. Have you noticed any improvement when they're in use? Are they worth it?
There is a discussion on modifications in Small Pahi Group which includes comments on daggerboards. Briefly I found the boards as designed of limited help. However before I threw them away I tried adding 0.5 M to the end of one. This was a success rather to my surprise as it looks all wrong. It made a huge difference. I have just the one and this also is fine. At my re-build I re-designed the case with a step to allow the top of the board go down into it below deck level about 12" [0.3M] as the extra height was untidy when the board was fully up. This allowed me reduce the length of the board and still let it down 30"/ 0.9M below the keel line.
Personally on a new build or if I had not got casings already I would try some kind of low keel. The kind of thing I have in mind is maybe 6ft /1.8M long approx. between first beam and amidships. Perhaps 6"/15cm deep ? and the same extra depth on the rudders also ?
The wing sail sounds good but the biggest problem I found with the cutter - the sails are just too small. The boat needs a 110% genoa in "normal" winds.
Thanks !!! Very like that !!! But perhaps farther forward ie. with end of keel at centre of boat ? I would love to know how this worked out ? Rudders also deeper ?
i don't know , i got it like that, i didn' t try without the keel, but i am very satisfied . For the fun i would like to increase 1/3 the surface of rudders and ad litle vortex board to the keel . If it doesn't give any improvement it will be easy to release .
Thanks Laurent. I have copied the photo to the Small Pahi Group where Pahi sailors will more easily find it in the future. I hope this is OK with you ?