Converting lift keel to electric operation

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irl2605

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Hi All .. Just putting the Bene 260 back together after its winter layup and once again the old Question of how to convert the 100 wind, worm type, lift mechanism to 12volt battery or hydraulic system has come up .. Anyone done it ? Have any ideas , Suggestions , All input welcome and considered.
 
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I'd say much more tricky than might seem at first.

Whatever you do, don't omit some sort of overload cut-off, microswitch etc to prevent panicked crew from keeping pressing the 'up' button on going aground; I know such a boat whose keel lifting wire broke with a very big bang letting the keel drop from full height because this microswitch was stuck, with nasty results.

Try Dutton Lainson, Nebraska, they supply manual winches for our Anderson 22 lift keelers, and they're a big company supplying winches of all sorts, nothing like them in the UK for sure - excellent service too.

I think you'll need a good electro / mechanical engineer at some stage ( design, then 'finalisation' ) as well; if you get stuck, PM me, I know one of the best in the world, just not sure if & when he's available...
 
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Cordless electric is used by two lift-keelers I know. A decent Makita job in one case on a Bene 25' or thereabouts (it's also his actual power drill by day if you see what I mean). He simply makes sure the battery is charged before he goes and it does the job for two or three lifts/drops at least. The other boat I think has a charging set-up from the boat's house battery.
 
Thanks for the reply's Guys .. I know this is the easiest option Grumpy but as Seajet so rightly points out the problem is knowing when its fully up. Rather like over tightening a bolt the treads will strip and the 750kg keel will drop. I have experienced this when an over enthusiastic crew member wound it up to far and stripped the keel nut .. A nasty bang was heard for some distance and the boat had to be lifted for repair .. Seajet I might give you a mail if I don't come up with any other ideas Many Thanks ..
PS was considering trying to adapt an outboard tilt motor. Anyone know a company that supply's/repairs them?
 
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Electro-hydraulic

I am interested in this thread and would like to see some electro-hydraulic suggestions, similar to the system used in the Southerlies, these work really well. The end of the ram is the full up position and when full up you hear the pressure release valve working, and it uses very little power to let the keel down, just enough electricity to open a valve.
 
Don't most rechargeable drills have a torque adjustment? If so, set it so that it just transmits enough power to wind the mechanism and will slip once it is fully raised.

Rob.
 
Winches or hydraulics, as suggested, seem somewhat irrelevant to an existing system that works by turning a screw. (OK, I guess you could replace the whole screw with a hydraulic ram, but that's a major reengineering.)

What's needed is a reasonably powerful motor, almost certainly with an integral reduction gearbox, probably a worm-drive one. A quick glance at RS shows they have over 200 different 12v geared motors, although I didn't look in any further detail. Other possibilities would be model robotics suppliers (think Robot Wars) or wheelchair motors are the classic source. Maybe a gutted cordless drill, but bigger ones tend to operate on more than 12v these days. Depends how hard you need to wind the handle.

Can't advise on mounting without seeing the winding rod in situ, but probably just a case of welding up some suitable bracketry, ideally stainless to save having to keep it painted, and some kind of adaptor between the motor shaft and the winding rod. You'd want to retain the ability to manually wind up and down if at all possible.

Stopping when fully up or down needs to be considered. Microswitches are one way, but of course they can stick especially if there's any water about (just before Christmas I finally traced my central heating boiler's erratic behaviour to a microswitch directly under a tiny leak, which had become gummed up and sticky). So you probably need a second line of defence in the form of an appropriately sized fuse or breaker. The centreboard version of my boat (for which I have the manual) has no automatic stop on its winch, but a self-resetting thermal breaker which will cut out after a couple of seconds' pulling against a fully-up board. My electric bilge pump insists on a fuse not just to guard against faults but as the designed response to a blocked strum box. Afraid I don't know how to calculate the right size fuse to blow when a certain mechanical load is exceeded at the motor, but someone else probably does.

Pete
 
Our TS has a s/h truck tail lift hydraulic pump fitted which gives push button lift and lower control. Keel can be raised in about 30 seconds.

Plenty of s/h pump units available off e bay make sure they are 12 volt not 24.
Also you could possibly use the hydraulic pumps now used on coupe cabriolet metal soft tops . You may need a bigger oil reservoir fitting as they tend to work on shorter stroke lower volume cylinders.

Pressure relief on pump and cylinder movement prevents any overloading of lift wire. Lowering is by solenoid valve. A restrictor at lifting cylinder ensures a steady rate of drop in the event of hydraulic pipe failure. Hydraulic cylinder is working at a loss so 600 mm of movement gives 1.2m of keel lift.

We use a 100 Ah battery with a small Solar panel and outboard charging for all the boats needs(TP, GPS and Chart plotter, Echo Sounder,Log, lights and Portable Cool Box) . Never found any problem with lack of power. We are not Marina based and often have to lift our keel to gain access at Pwllheli at low tide.

Pump is wired directly to battery with good heavy conductors and correctly fused. Our manual pump can be quickly reintroduced into the hydraulic circuit given electrical failure.

Pm me for more info and photos if interested.
 
rob2 said:
Don't most rechargeable drills have a torque adjustment? If so, set it so that it just transmits enough power to wind the mechanism and will slip once it is fully raised.
Click to expand...

macd said:
They certainly do. Way to go.
Click to expand...

I'm inclined to agree, as long as the load on your handle is low enough that a 12v drill can cope. I've never used a keel like this, so I don't know how hard work it is to turn. 12v is at the low end of the cordless drill range - 18v is common for full-size machines.

If 12v is enough, this could be very easy. Ready-made over-run protection which you can hear working and take your finger off the button. Easy to chuck in an adaptor for the turning rod. Just need to open up the drill and fabricate a mount for the guts.

The case of the drill might be structural, especially around the gearbox area, so you might have to leave it intact and mount the case somehow (maybe with the handle sawn off). Bigger drills have a standard-sized collar just behind the chuck for accessories like handles - you could attach your mounts to this.

Pete
 
Hydraulic kit gives immense power, but beware the lack of human 'feel', this is a worry for pilots as well as sailors, in aircraft the attempts to give the user some feedback vary from separate minor hydraulic systems to springs on the column, guages and lights, now with artificial feel through fly by wire, just the same as a 'Force Feedback joystick' as used by computer gamers...

While smaller scale and a long time ago now, it's possibly worth noting that the Hunter 701 had an hydraulic lift keel, which caused I understand a lot of problems re. seals and pipes corroding etc.

The improved design by the same designer ( Oliver Lee, there is a group set up here on 'community' to celebrate his designs ) Anderson 22, 950lb plate & ballast bulb has a simple manual winch, ratchetted on the way up, braked on the way down.

On Barracuda lift keelers' I heard the main propulsion engine ( thereby charging alternator ) has to be run during any keel up / down.

It may be worth noting that Anderson 22's with their manual keel winch are still going strong, in fact I'm in contact with the new owner of the 3rd built from 1973, but I have not seen or heard of a Hunter 701 for many years; there are 6 Anderson 22's at my club in Chichester Harbour with the possibility of a 7th joining, just at one club; so the essence is, keep it simple.

I strongly suggest any system should 'fail safe' as in keel down, incidentally Oliver Lee had the sense to design this into the Anderson - a pain once in a lifetime having to keep to deep water, but not so much of a pain as being inverted by big seas !
 
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Seajet's post makes sense, but really only for someone designing a keel system from scratch. That's not the case here - the OP already has a screw-driven system he's happy with apart from its manual aspect, so the challenge is simply to turn the screw with electrics. Not to replace it wholesale with hydraulics, tensioned wires, super-high-modulus knicker elastic or anything else.

Pete
 
Just popped back in to see if there was any feed back and wow .. Many thanks to all.
A few things have been said that need clarification. The Keel is a swing keel weighing 750kg and it takes 100 hard winds to bring it up or down . It is not a great system as the full weight of the keel hangs off a 3" approx coarse brass or probably bronze nut at all times, unless the keel is in the down position. However we have to moor with keel up. It is mounted on the end of a tube which is rotated by a standard winch handle and the worm winds up into this tube to shorten the throw and so lift the keel. If this nut fails the keel swings down ( preventing us getting into harbour ). This has happened twice in 5 years.
I was thinking maybe an electric winch devise and using the original for back up. It is all mounted on the middle of the table and the tube gets pushed into the boat if we hid ground, so no problem with a second lift mechanism..
The unit is only serviceable while hanging from a crane.
Pics show Mech. out saddle at end is bolted to keel about 1/4 way back from the front and it is hinged just forward of that. Second pic is keel in up position.
Iain
 
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I think your biggest issue is working out when the keel is fully up or fully down, could you have some sort of micro switch that when fully up lights up a bulb ?. I have an e-boat with a lifting keel but it is like a centre board in terms of comes straight up/ down. I use a 4x4 winch to pull a 6mm dynema rope (I appreciate that this may not help you, but may help somebody with a different lifting keel). I have a 100ah battery with it's own on/off switch for the keel as I have to be able to get on/off moorings and can not run out of juice. Last year I bought a reversing solenoid which when I finally found a wiring diagram for a two terminal winch is great and makes the electrics safer than my previous heath robinson effort.
 
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