Adding a mechanical tie bar

[mikedefieslife]

I've got a Prout Snowgoose 35 with twin transom hung rudders.

I run a hydraulic steering system with two vetus MTC72 steering rams linked together in series with a fluid tie bar. Each ram is capable of 706Nm of torque.

The setup works well, and I carry a spare good ram as a backup and plenty of hydraulic fluid.

All that being said. I would like to have a mechanical tie bar on board for added security. On a recent 200m passage, I found the autopilot doesn't function well under sail (25knt winds, 3m swell on aft quarter) on a singe rudder.

The distance between the rudders from eyelet to eyelet is 306cm. I'm wondering what is the best way to approach getting a suitably strong bar made up?

Ideally the bar would have some adjustment, and be able to separated into two pieces for storage.

I also need to figure out what material, and size it should be from. 32mm 316 steel tubing, carbon fibre, or something else.

[atoll]

on the elite the tie bar is 1" 316 probably (12guage,1.5mm).with female threaded ends welded on for adjusting the couplings,which are 7/16UNF(12mm~)

[micah719]

Is this your boat?

SNOWGOOSE 35 (PROUT) sailboat specifications and details on sailboatdata.com

Have you any other uses for the bar/s aboard?
What kind of budget had you in mind?

[motion30]

The tie bar itself is a fairly simple fabrication, you can get a the spherical rod ends in 316 stainless from many vendors check online at car McMaster. The only question is how can you connect those to the Rudders I'm sure something will need to be fabricated in stainless

[mikedefieslife]

Originally Posted by micah719

Is this your boat?

SNOWGOOSE 35 (PROUT) sailboat specifications and details on sailboatdata.com

Have you any other uses for the bar/s aboard?
What kind of budget had you in mind?

Yep that's the boat.

No other uses for the tube as it would be too short for a whisker pole.

Current Plan is to get a tube of 316 and have nuts welded to the end to screw in the track rod ends. It would just be nicer if their was an easy way to split the tube for storage.

Coupling to the rudders is easy (at the dock or in anchorage) as they have long drop arms that my two rams attach to.

Budget is probably a few hundred euros if necessary.

The basics of it are simple. I guess it can get complicated if I want fancy materials, or two rods hooked up to a centrally mounted universal joint.

[john2445]

Just cut the tube in half (or get 2 shorter pieces), thread the ends and use a plumbing type coupling. Or get a piece next size larger to use as a sleeve and drill thru for a bolt. I would prefer the 2nd as it's simpler to make and you can make the sleeve as long (strong) as you want.

[JOHNMARDALL]

John Mardall here, from Vetus Maxwell Group. If you can provide some more information, I will try to help. You mention that the autopilot was working on one rudder, but at least in a conventional hydraulic steering system, the autopilot is controlling an electro-hydraulic pump which works through the complete system, moving both rudders. If you are using some form of tiller pilot moving one of the rudders mechanically, are there by-pass valves on the cylinders to allow them to move independent of the hydraulic system? A solid tie bar would connect the tiller arms, but those are usually below deck, so that to connect them on a catamaran would require the tie bar to pass through the inner topsides of the hulls, which is the main reason for using a hydraulic tie bar. Etc., etc.- more info please.

[Cadence]

Originally Posted by mikedefieslife

Yep that's the boat.

No other uses for the tube as it would be too short for a whisker pole.

Current Plan is to get a tube of 316 and have nuts welded to the end to screw in the track rod ends. It would just be nicer if their was an easy way to split the tube for storage.

Coupling to the rudders is easy (at the dock or in anchorage) as they have long drop arms that my two rams attach to.

Budget is probably a few hundred euros if necessary.

The basics of it are simple. I guess it can get complicated if I want fancy materials, or two rods hooked up to a centrally mounted universal joint.

Take a rough sketch of what you want to a local machine shop. The guy making it may surprise you if he has been a machinist for years.

[mikedefieslife]

Originally Posted by JOHNMARDALL

John Mardall here, from Vetus Maxwell Group. If you can provide some more information, I will try to help. You mention that the autopilot was working on one rudder, but at least in a conventional hydraulic steering system, the autopilot is controlling an electro-hydraulic pump which works through the complete system, moving both rudders. If you are using some form of tiller pilot moving one of the rudders mechanically, are there by-pass valves on the cylinders to allow them to move independent of the hydraulic system? A solid tie bar would connect the tiller arms, but those are usually below deck, so that to connect them on a catamaran would require the tie bar to pass through the inner topsides of the hulls, which is the main reason for using a hydraulic tie bar. Etc., etc.- more info please.

Probably easier to PM you as story of the one rudder will detract from the conversation.