Worm Gear Steering

[maartenvh]

Hi everyone,

I have an opportunity to buy a great looking vessel from 1975, which requires a bit of work, but nothing I feel uncomfortable taking on.

However, the sailboat has worm gear steering. I'm entirely unfamiliar with this and have actually never even sailed a boat which had such setup. At first it confused me, since the steering wheel appears to be mounted backwards.

Before I make a purchase decision, I wanted to get a few opinions from the community:

• When selling the boat at a later point in time, will worm gear steering count against its value? Is it generally considered an ancient relic that is to be avoided when purchasing a boat?
• How does worm gear steering generally work out on the ocean? Any experiences with sailing a blue water cruiser using worm gear steering?
• Anyone who has ever been able to mount an auto pilot (not a wind vane) on a steering wheel with worm gear?
• Any experiences with converting worm gear steering into a more regular steering system? The cockpit is quite narrow and probably wouldn't allow it, but outside of this, any reason why this is not possible?

Thanks so much for your guidance. I'm new to the boat buying process, and any help you could provide would be much appreciated!

Cheers,
Maarten

[zeehag]

less weather helm with worm gear steering system.is a most efficient and safe way to steer a boat. why would you wish to change it?? you may wish to research first before deciding-- donot do anything rash.

[squarerigger]

I would say that of all the mechanical steering mechanisms available, in my experience worm gear steering is the most robust and dependable there is. An Alden yawl I once owned had such a gear that was still in perfect order after 62 years of use. Presently, one ship in my museum's collection has a worm gear 148 years old and still going strong after 21 circumnavigations, each including a rounding of Cape Horn (though the wheel box and wheel it was attached to was smashed on one occasion). Another one of our vessels has a Lunenburg worm gear now 28 years old with no signs of wear after almost constant use. Having said that, these relatively massive gears all have a bit of play and would not seem especially suited to the attachment of an autopilot and indeed, none of these vessels ever had one.

[klem]

What make and model of boat are you looking at?

Worm gear steering is hard to beat from the standpoint of how tough it is as squarerigger points out. My boat has a 32 year old Edson worm gear unit which still looks quite good. I also worked on a vessel with a 10" Lunenberg double worm gear unit that was great. I have seen one broken gear on a very large and very old unit but this certainly seems like a very isolated incident to me and I would not be concerned about reliability provided that it is in good condition and properly sized.

The real downside to worm gear steering is that the friction in the system is almost always higher. This means that the helm does not give you as good of a feel of what is going on. The advantage of this is that you usually don't have to work quite as hard when it is rough (kind of like applying a friction brake partially to help you hold the wheel). For blue water I really like them but for racing, I would want something else. Another small annoyance is that there is a little bit of slop in the gears but this is very little on well made units.

An autopilot is independent of the worm gear, it is more related to the fact that you are looking at a schooner style wheel. It is possible to put an autopilot on this type of wheel although it sometimes involves replacing the wheel itself. You end up bracing the autopilot off of the wheelbox. If it is a larger vessel, you could also add an arm to the rudder post for the autopilot and you would need to make sure that the worm gear is not in the way.

By the way, there are actually multiple kinds of worm gears available. Most units have a single gear and will use either one or two wheel shaft bearings. The larger units found on fishing schooners and cargo vessels often have two worm gears that are opposed and a hinge mechanism. These only use 1 bearing and the wheel shaft actually oscillates back and forth. If the hole for the shaft in the wheelbox is actually a slot, it is usually this type of unit.

[rebel heart]

I have a 1975 Hans Christian with worm gear steering. It's bullet proof for the displacement of our vessel I don't think there's a better option. I've been extremely happy with it.

The only "disadvantage" is that there's more friction (which is good in a lot of ways) so auto pilots need to work a bit harder, and if you get a self steering wind vane you're better off with an auxiliary rudder model.

Worm steering is great. If you try to covert it to cables and pulleys you're going to get a lot of raised eyebrows. You can certainly do it, but you're going from great to good.

[rtbates]

Form my limited experience of sailing two boats with worm gear the only drawback for me was the lack of 'feel'. Felt more akin to steering a barge
or bus. As others have mentioned they are about a bullet prove as you can get, notwithstanding my prefered method, a tiller..But with a tiller you had better know how to balance your vessel. The feel comes from lack of leverage and friction...

[rebel heart]

Originally Posted by rtbates

Form my limited experience of sailing two boats with worm gear the only drawback for me was the lack of 'feel'. Felt more akin to steering a barge
or bus. As others have mentioned they are about a bullet prove as you can get, notwithstanding my prefered method, a tiller..But with a tiller you had better know how to balance your vessel. The feel comes from lack of leverage and friction...

That "lack of feel" was sort of where I was trying to go with the friction thing, but you're right in that you'll feel it as a "lack of feel". The plus side is that you can leave the wheel in position and walk away for a minute even in pretty heavy conditions and it won't move.

I don't know if my vessel falls into the "too big to tiller" range, but I know at some point the tiller just doesn't offer enough leverage (or the arm would need to be 20' long and sweep the decks).

If I had to pick, and all would work on whatever vessel, I'd certainly pick a tiller over a worm drive.

[SkiprJohn]

As far as I'm concerned worm gear is the best. Everything else is for racers and kiddie boats. Rack and pinion might come close.
kind regards,

[Paul Elliott]

Originally Posted by zeehag

less weather helm with worm gear steering system.is a most efficient and safe way to steer a boat. why would you wish to change it?? you may wish to research first before deciding-- donot do anything rash.

There is practically no "feel" or "feedback" with a worm gear. Your boat may or may not have weather helm, but you won't feel it at the wheel. What you will feel is more or less resistance when you turn the wheel, but when you're just holding it steady there will be no force.

Personally, I like the feel of my gear steering (not worm gear). Having a little pressure on the helm helps me steer by feel. I've not spent any time with a worm gear though.

[Leopotter]

My wheel won't turn. The system seems fine, was caked in salt but all clean now.