A Photo & Discussion Forum for Wharram Design Enthusiasts
I've just bought 'Jumpa Lagi' a Tiki 38', and I have a question regarding the steering, hoping someone out there might be able to answer... I've attached photos to illustrate.
The cross beam which joins the tillers, is located about 2/3 the distance from the rudders, leaving the curved part of the tiller non-operational (unless hand steering). This seems to me to add a lot of effort to the steering, and I'm wondering if this is why the (little) autopilot on this boat doesn't cope..?
It also seems to negate the effect of the curved tillers because they're straight from the steering beam aft, so my question is... can I, or should I, move the steering beam forward on the tillers to reduce the effort and to derive the benefit of the curved tillers?
I realise this will mean more turns on the wheel, but I'm guessing also less effort.
I can see we might have to re-run the main sheet to avoid the beam if we move it forward, but that looks easy enough.
Many thanks for any advice, and I look forward to becoming a member of the Wharram family.
Best to all,
Hi Norm, indeed it looks like the tiller connection is too close to the aft beam. Maybe it is just the photo, but you can mesure it, it should be about 100cm form center aft (tube)beam to the connection tillers/ cross beam.Maybe you should check this and have a glimpse on the original plans.
The only advantage to having the tiller bar aft is for deck clearance. You can move the steering line connections forward on the tillers. This will increase your steering leverage. It will also increase the load on the tiller itself. To get any ackerman effect the tiller bar must be moved up into the bent area. "Normal" would be about 6" from the forward end of the tiller.
Thank you so much gentlemen, yes the 'Ackerman Effect', I remember reading about it (from James) many years ago, but couldn't remember the name. Daniel, the steering beam is about 100cm forward of the aft crossbeam, but I like the idea of moving it to 6" from the end of the tillers, otherwise, why bother building in the curve? This will reduce the loads on the steering lines and the wheel, although there'll be more turns lock to lock. Perhaps I'll increase the size of the drum that rotates the steering lines, behind the wheel, to compensate for the extra turns...
I've just fitted a radar on the starboard aft deck, it sits on a 3m stainless pole currently (temporarily) braced with 4 lines lashed down to the toerail. It's a bit floppy now, but I'll install stainless wires and straps as soon as I can, and I'll let the community know how it all goes. It might be seen as excessive, but as an ex-commercial skipper, I love the security radar provides ;-)
Currently heading for a typhoon refuge in Puerto Galera, in case there's any other Wharrams about...
Thanks again for your responses,
some pics of our new radar installation and the position of the steering beam.
The lines bracing the radar pole are temporary, we'll install stainless wires and straps as soon as possible.
I'm going to try moving the steering beam forward to about 10cm from the end of the tillers, and will post the results.
Happy sailing ;-)
Hi Norm, so your tillers are not built according to the plans. I build mine exactly like the plans and 100cm away from the aft beam there is a lot of curve!