Connecting a new Raymrine linear drive to a steering quadrant

[meb]

I have a 1987 Beneteau First 405 and wish to fit a Raymarine EV 200 autopilot with a ST1 linear pack to steer the boat. Fixing the linear drive direct to the rudder stock would be the strongest connection and give independence from the wheel steering system. The rudder stock square section top protrudes through sole boards in the cockpit locker but needs to allow the emergency tiller to slide over it. The rudder quadrant is fixed by two bolts nipping together a slotted hub which grips the rudder stock. Connecting a fabricated lever to the two bolts would mean the linear drive motor would interfere with the sole boards.
There is little room under the quadrant and the top rudder stock bearing and it is not clear what is the shape of the rudder post at that point. if it is square then maybe a lever with a similar hole through it could be slid down after taking off the quadrant. Assuming the rudder does not fall off.

The last option would be to buy or fabricate two plates to sandwich say 3 spokes of the quadrant to spread the stresses and bolt through. This latter would probably mean fitting the linear drive upside down.

Has anyone managed to fit such a linear drive and can you please tell me how it was done? Or other suggestions welcome.

Thanks

Mike

 

[anoccasionalyachtsman]

Could you make a lever to fit on the top square section where the emergency tiller currently goes, and have another identical square section attached to the top of it as the new emerg. tiller location?

 

[GrahamM376]

The last option would be to buy or fabricate two plates to sandwich say 3 spokes of the quadrant to spread the stresses and bolt through. This latter would probably mean fitting the linear drive upside down.

That's how our was/is mounted by previous owner except with single plate around 4mm bolted through the quadrant web.

 

[lpdsn]

The last option would be to buy or fabricate two plates to sandwich say 3 spokes of the quadrant to spread the stresses and bolt through. This latter would probably mean fitting the linear drive upside down.

Has anyone managed to fit such a linear drive and can you please tell me how it was done? Or other suggestions welcome.

Thanks

Mike

The original fit on my boat had a stainless steel plate connected to the quadrant. It lasted 16 years but did eventually cause the quadrant to fail. I still have the s/s piece. If I get spare time tomorrow I'll try to post photos.

I eventually bought a Jefa Duralium qudrant with a fitting for the linear arm welded on. Premium quality. Premium price.

 

[yoda]

Could you not have an arm made that would fit on in the same way the emergency tiller does to carry the linear drive. You could possibly have it made in a way that the emergency tiller could also then fit on top of the new arm should it be required.

Yoda

 

[Rafiki]

The last option would be to buy or fabricate two plates to sandwich say 3 spokes of the quadrant to spread the stresses and bolt through. This latter would probably mean fitting the linear drive upside down.

This is how mine is set up, different boat though.


Mike[/QUOTE]

 

[knuterikt]

If the quadrant is similar to this I would not attach the linear drive to it - it's not designed for point loads.I got this tiller arm from Jefa, they have tiller arm that can be machined to fit, this one is clamped to the rudder shaft with four bolts.

 

[DownWest]

The quadrant above is, as noted, not up to having a point load. I refurbed a hydraulic actuator on a Swan 431 from the 80s, it had a much more substantial quadrant that had been drilled to accept the pivot. So, dépends on what you have.

 

[meb]

Thanks for all your ideas.

My quadrant is similar but the clamp to the rudder stock has four substantial bolts. I have sketched port and starboard plates that could rest on top and within the `quadrant bays`and grip the centre vertical web and have vertical tabs at the quadrant hub to take the four bolts.

My guess is that these web `strengtheners` could be fabricated from 6-8mm SS and extend over the rim of the quadrant to accept the drive pin. I do know how to upload my sketch to this ste!

 

[GrahamM376]

This my plate, the drive is fixed to pin welded on the underside, the rps on top.

 

[meb]

A simpler solution may be to fabric two thick nylon `bay inserts` to place snuggly within the quadrant bays and through bolt SS straps from the quadrant hub under the nylon inserts to beyond the quadrant hub to meet with a suitable pivot point fabrication.

The nylon inserts will provide a degree of shock absorbtion and distribute push/pull stresses. Perhaps fabricated from chopping boards?

I will try once again to upload my diagram.

 

[ex-Gladys]

The force these things deliver is huge, when looking at installing an underdeck on Gladys last winter, the force on the 250mm additional tiller arm was 400kgf, so the mounting has to be very robust. As someone said earlier, I'd be going for a Jefa additional tiller arm

 

[knuterikt]

Can you reuse the four bolts and design something similar to this?
An angled piece like in this picture bolted on with the existing four bolts. The arm should be solid enough to drive the rudder without any more support.

I don't think sharing the load at the hub will be a big deal, more concerned if you try to transfer load to the spoke/rim of the quadrant.
Introducing unnecessary flex does not sound like a good idea, flex must transfer to the fixing bolts.

more pictures here http://www.lp-yacht.dk/bade-og-udstyr/autopilot-beslag/galleri

Is your quadrant like this

 

[cmedsailor]

This is what I have in my Beneteau Oceanis 361. A strong plate attached at the quadrant.

 

[Rafiki]

I think the conclusion from this interesting thread - well interesting to me as I too am about to change my Autopilot set-up- is that ideally the autopilot should drive a separate "tiller" connected to the rudder post, but a widespread practice is to connect them to the steering quadrant after adding suitable re-inforcement.

 

[GrahamM376]

I think the conclusion from this interesting thread - well interesting to me as I too am about to change my Autopilot set-up- is that ideally the autopilot should drive a separate "tiller" connected to the rudder post, but a widespread practice is to connect them to the steering quadrant after adding suitable re-inforcement.

On my previous boat, I welded up a tiller arm which bolted to the rudder post. This one already had the plate on the quadrant. In operation, no difference whatsoever but, some quadrants could be weakened by drilling and fixing a plate whereas some may even be strengthened. Your decision as to which suits your boat.

 

[wizard]

At least no one is mentioning drilling into the rudder stock itself to complete the system.

It is worth reminding everyone about the Hanse yacht some years back that sank off Ireland after a transatlantic crossing due to the autopilot connection (as above) weakened the stock, it split, the rudder fell off and the inrush through the hole did for the yacht.

 

[lpdsn]

At least no one is mentioning drilling into the rudder stock itself to complete the system.

It is worth reminding everyone about the Hanse yacht some years back that sank off Ireland after a transatlantic crossing due to the autopilot connection (as above) weakened the stock, it split, the rudder fell off and the inrush through the hole did for the yacht.

No mention of drilling into the rudder stock in the MCIB report on the loss of Megawat. http://www.mcib.ie/_fileupload/Documents/reports/Megawat_11_06.pdf Where did you get your info?

Obviously not a good idea to drill into the rudder stock without input from the designer or other suitably qualified person.

 

[Ric]

I have a 1987 Beneteau First 405 and wish to fit a Raymarine EV 200 autopilot with a ST1 linear pack to steer the boat. Fixing the linear drive direct to the rudder stock would be the strongest connection and give independence from the wheel steering system. The rudder stock square section top protrudes through sole boards in the cockpit locker but needs to allow the emergency tiller to slide over it. The rudder quadrant is fixed by two bolts nipping together a slotted hub which grips the rudder stock. Connecting a fabricated lever to the two bolts would mean the linear drive motor would interfere with the sole boards.
There is little room under the quadrant and the top rudder stock bearing and it is not clear what is the shape of the rudder post at that point. if it is square then maybe a lever with a similar hole through it could be slid down after taking off the quadrant. Assuming the rudder does not fall off.

The last option would be to buy or fabricate two plates to sandwich say 3 spokes of the quadrant to spread the stresses and bolt through. This latter would probably mean fitting the linear drive upside down.

Has anyone managed to fit such a linear drive and can you please tell me how it was done? Or other suggestions welcome.

Thanks

Mike

Which quadrant have you got? My boat (Jeanneau) has a Goiot quadrant and that has a lug at the forward end with a hole through it which is specifically made to attach a linear drive.

 

[wizard]

No mention of drilling into the rudder stock in the MCIB report on the loss of Megawat. http://www.mcib.ie/_fileupload/Documents/reports/Megawat_11_06.pdf Where did you get your info?

Obviously not a good idea to drill into the rudder stock without input from the designer or other suitably qualified person.

The rudder itself washed up a long time later, Ireland I think, so the split area was identified. Info from Hanse employee, as I had a Hanse 312 at the time.