J Class Genoa boat running rigging gubbins control

[@gudmundthompson734]

Very nicely done. I love this boat. I used the same hull to produce a boat with a Friendship rig (three overlapped headsails and a gaff rigged main with topsail) with the mast supported by functional running backstays. I used an ARS winch servo to control the main and jumbo jib, and a pair of them to control the port and starboard headsail sheets. There are also a pair of 25 kg servos serving to trim one of the foresail sheets on each side, another for the rudder, and a pair of 35 kg servos on the running backstays. My computer radio is very busy with lots of mixing, but it all sails like a dream. I can even give the local EC-12s a run for their money in light to moderate wind conditions.

[@SydneyGrimes-uw3mh]

Very nice and professional. I've got a J class rc yacht that's waiting for me to build I'm busy building the Queen Mary 2 RC ship at the moment. J class rocks

[@WestburyDF65races-fb1bf]

Thank you, it is a bit overcomplicated but it was my first attempt. It is such a lovely boat to sail so I have started another one using the lessons learned from Topaz. I have come up with another mad idea for the running rigging and if it all works out I will do an updated video of my new boat.

[@davidcraig4253]

Wow. Now, I'm looking forward to buying a shed to do such a project

[@chinachile]

No need for a shed, I built mine on the kitchen table😂

[@davidcraig4253]

@chinachile I have 3 more. Also, I am starting to repair them.

[@hobbyoverload]

Impressive!!🤗

[@StuartMunro-y3x]

So much going on - I'm about to build a 60" J and whilst keeping it simple, would like to add the backstay. How well does it work, especially the Actuonix servo and its ability to hold position? And given the J is a wet boat, is water ingress through the rear tube a problem?

[@chinachile]

Hello, great idea to keep it simple which is what I will do on my next one, lessons learned. In my opinion the movable backstay is a huge help when rigging and on the water as I can flatten the mainsail while tightening up the forestay and seems it to work well on a beat while slackening off seems to help when on a run. The Actuonix servo is more than powerful enough to fold the boat in half and locks in position with no electrical load.....once locked it will NOT move. I raised the lead out for the backstay about 25mm above the deck and could not say if water gets in there or not but the hatches lead to the biggest ingress of water as I don't think I did a particularly good job on the seals. The actuator I used is the "Actuonix L16 actuator 50mm 150:1 6V rc control linear actuator"

[@StuartMunro-y3x]

@@chinachile Thanks - very helpful. nb, on a 48" I built a couple of years ago I used silicone bath seal on the rear hatch - can access by cutting the sealant with a sharp nife, but rare that I need to. On the front hatch I placed a thin pieve of ply (1/64th) right over the hole, under the hatch. This is sealed again with silicone bath seal. Inset into this ply is a IOM type access lid (sailsetc2). I can access the battery through this, and leavce it open to air. But the whole thing is just about 100% watertight.

[@StuartMunro-y3x]

@@chinachile I actually love the systems you have built into the boat. But on th ebackstay in particular, I found an excellent review of the Actuonix L16 series on You tube called "Test of Actuonix L16 linear actuator". It did show one possible issue - which may have related to the individual unit having a fault. The test unit tended to oscillate around the 'set' position. This did settle down after a while in most instances. But on the plus side it had very good 'hold' once settled. I've asked for other experience with it (Facebook). Did you experiment with any alternative servos?

[@StuartMunro-y3x]

A footnote. Excellent service from Acturonix. Answered my question on this in 30 minutes. Put simply, the hold force (Backforce in their terminology) is about 50% of the power of the servo. So if the pull on the backstay exceeds the Backforce but is within the capability of the servo's power. Each time it reaches the set position power goes off and it moves. Power comes on to correct - and so on. Oscillation. Martin overcame this with a simple one pulley mechanism inside. I'm thinking of two pulleys outside, one fixed to the deck and another to the backstay. Should look good, reduce the strain on the servo to 25% and also fascillitate a through deck water resistant pulley because the force is minimised. Still Martins brainchild, just my variation on a theme.

[@cosmiccolonel]

Just trying to get my head around this is causing a migraine, god knows what it did to you….. looks awesome though 👍👍👍

[@WestburyDF65races-fb1bf]

All joking aside, I was recovering from a pretty serious head injury when I strung the boat up but had enough nous to record my madness. It sort of makes sense to me but I will do it differently and a bit more orderly next time : )

[@cosmiccolonel]

@@WestburyDF65races-fb1bf funny you should say that…….. I’m recovering from a pretty serious head injury too !!! Just got my first two rc yachts as part of my therapy! I’m planning on building a J class once things are a bit more settled, head wise…. Hope your feeling better after the tbi……