Time To Improve The Steering On A 60ft Cat

[sharkbait2035]

Hey,
so I've decided the old steering system on our cat has to go...
currently there is a single hynautics ram attached above decks to the port rudder with an aluminum linkage bar running to starboard...
firstly there are the component problems - the plates used on the linkage were made from cheap steel, so even after blasting, grinding and powder-coating, they are rusting again.
Also the whole setup makes the space between the sterns virtually unusable, and I would like to modify it to include a swim/dive platform at some stage, would be nice to be able to use the back tramp with out having to dodge the crossbar!
I guess what I'm after is feedback from cat owners who have twin hydraulic rams on their boats, pros and cons, and what brands to look for or avoid.
I guess I should add, that the other options seem way too difficult to engineer - rack and pinion or push/pull cable set ups, so its either modify what is there atm, or the dual ram, below decks option...
ideas???

[mikereed100]

My cat originally had a single ram and tiebar like yours, but when I rebuilt it I put in a system consisting of 2 rams with a "liquid tie bar" connecting them. There is a bypass valve in case the hydraulics fail and I have to steer by hand. I used Uflex rams and pump with nylon tubing. I looked into systems using copper tubing (Hydrive etc.) but they were far more expensive and would have been very difficult to retrofit with all the bends and turns. The Uflex system was very simple to install and so far it has worked flawlessly, the rudders staying in alignment without need for adjustment.
Friends with a similar size cat but smaller, older rams have had trouble with the rudders going out of alignment despite new seals, presumably due to wear, combined the greater demands on them due to the cylinder's smaller size. If such a system does get out of alignment, correcting it is a simple matter of opening a bypass valve, straightening the rudder, then closing the valve. Takes just a few seconds.

[Cotemar]

Just move everything below deck.

Single hydraulic ram attached below decks to the port rudder with an aluminum linkage bar running to starboard

[sharkbait2035]

Originally Posted by mikereed100

My cat originally had a single ram and tiebar like yours, but when I rebuilt it I put in a system consisting of 2 rams with a "liquid tie bar" connecting them. There is a bypass valve in case the hydraulics fail and I have to steer by hand. I used Uflex rams and pump with nylon tubing. I looked into systems using copper tubing (Hydrive etc.) but they were far more expensive and would have been very difficult to retrofit with all the bends and turns. The Uflex system was very simple to install and so far it has worked flawlessly, the rudders staying in alignment without need for adjustment.
Friends with a similar size cat but smaller, older rams have had trouble with the rudders going out of alignment despite new seals, presumably due to wear, combined the greater demands on them due to the cylinder's smaller size. If such a system does get out of alignment, correcting it is a simple matter of opening a bypass valve, straightening the rudder, then closing the valve. Takes just a few seconds.

sounds like what I was planning on doing Mike, wondering if you had any below deck photos, still trying to decide what to do re tiller length/connections etc.
Terry

[sharkbait2035]

Originally Posted by Cotemar

Just move everything below deck.

Single hydraulic ram attached below decks to the port rudder with an aluminum linkage bar running to starboard

would like to be able to keep it that simple, but unfortunately there is no where I could run the linkage as the rudders are a couple of feet back from the transom... although, looking at yours, I may be able to sneek it over the top of the fuel tanks if I extend the tiller/quadrant attachments.... something else to check out, thanks!
Terry

[mikereed100]

Terry,

The extension of the hydraulic cylinder you choose will determine the tiller length. For example, the UC215 cylinders I used specify a tiller length of 7.8" with a stop-to-stop extension of 9" on the rams. If your rudders are behind the crossbeam, as mine are, the only way you can use a tiebar through the crossbeam or beneath the deck would be to use a linkage between the tillers and tiebar. I considered this but in the end realized it would be much simpler to simply use two cylinders and a "liquid" tie-bar.

[daddle]

Nice to hear some systems don't get out of alignment. A friends cat gets dangerously out of alignment is a few hours - usually not discovered until slowing to maneuver in a tight spot. Easy, but not trivial, to re-align. Both aft hatches need to be opened. Silly design.