Rudder control

[Robin BodgerParticipant @robinbodger80379]

Firstly Thank you for all the great help with motor battery selection, I am now an brushless lipo convert. The mas500 stearing was controlled by wirerope moving a tiller, two cables came out of the bridge, ran the length of the boat and attached to a tiller at 90° either side! Is this possible at 124 scale? Wot ropewire ? Wot servo? This is the first boat I’ve ever built, I can make anything and can make it work, just trying to avoid the trial error process. TA folks, you’ve all been truly brilliant up to now and will post pics footage of it running if it works.

[Robin BodgerParticipant @robinbodger80379]

[Mark Jarvis 2Participant @markjarvis2]

Robin the first thought that came to mind was use 2 servos on a Y lead, one to pull starboard and the other to pull port, or 1 servo and small pullies to take the rudder wire into the bridge structure, sounds like you could be another Ashley!!!! he loves a challenge

Mark

[Kev.WParticipant @kev-w]

For rope, try Mobile Marine, they make their own in different sizes.

**LINK**

[Robin BodgerParticipant @robinbodger80379]

My idea was a 360? servo drum, 3 coils round drum, winds in, unwinds, pulling in and giving out at same time, are the yacht servos quick enough? Are they strong enough?

[Robin BodgerParticipant @robinbodger80379]

The cablesropes came out sideways from the bridge, went thru a block on each side, ran down the length of the boat, thru another block and joined at the tiller. Seems more fun than just a hole and push rod thru the stern.

[Colin BishopModerator @colinbishop34627]

It should be quite possible to make such a system work but you might have problems in getting the slack out of it.

Colin

[Dodgy Geezer 1Participant @dodgygeezer1]

Scroll to the bottom of this page to see a simple closed-loop system operating a tiller for the small EeZeBilts:

**LINK**

[ashley needhamParticipant @ashleyneedham69188]

I have used conger fishing trace . It is stainless steel, so doesn't stretch, and is covered on a clear plastic coat. Looks like wire rope. At the servo arm end, or indeed in the run under cover somewhere you could put a strong spring (closed sort with loops at either end) to tension the system.
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Assuming there is not too much load on the servo from the run, incl pullies and so on I should think you have a chance. Any ordinary sized servo should be ok. You can get small working brass pulley wheels to lead the rope around the corners.

Ashley

[Dave MilbournParticipant @davemilbourn48782]

I've no idea what a mas500 is but I'm pretty familiar with this sort of linkage from Clyde Puffer models. I would fit a hidden "standard" rudder linkage (i.e. a tiller arm and a normal servo) below the aft deck and fit dummy rope/chain/pulleys, tensioned with a light rubber band or spring just to keep it looking real. That way the 'false' tiller operates the dummy linkage and you have a reliable rock-solid link to the rudder elsewhere. Winch servos aren't very suitable for steering because they don't "centre" precisely. This is due to backlash in the high gearing between the output shaft and the internal pot.

Her are a couple of sketches I drew for Gareth Jones' Spyder-J project

Suit yourself , m'duck – I love chucking spanners into the machinery!

DM

Edited By Dave Milbourn on 04/10/2016 12:14:09

[Gareth JonesParticipant @garethjones79649]

Robin,

Some years ago I built a Mountfleet Osprey armed steam drifter which had a similar arrangement to yours except that the linkage from the wheelhouse to the rudder bar on the real vessel is by chains that run partially through some conduit/piping.

I used the method described by Dave in the text above (not the diagrams) The rudder was directly driven by the servo, mounted under the deck. The visible rudder bar above the deck was connected to the drive chains on each side and these were tensioned at their forward end by a piece of light elastic which formed a hidden loop, ie. both front ends of the chains were connected to opposite ends of the same piece of elastic. This minimises the load on the servo but keeps the chains tight so they move in a representative manner and provides a positive drive to the rudder, directly from the servo.

I did not go with the system describe by Dave above on my Humber sloop, Spider J because I thought I had come up with a better method. However my design still leaves a bit to be desired as it tends to have too much backlash so it still needs a bit of development.

Gareth

[Robin BodgerParticipant @robinbodger80379]

Think I’m going to try ‘dodgy geezers’ link idea, but with a sliding collar on the servo and tiller arm to keep cables same length, and start with fishing trace, I can crimp that to secure each end, too late to change my mind, just bought the servo and trace!! Thanks again for all your posts, everyone had a valid point and useful advice. Most usfull forum I’ve ever come across.

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