Winch Project


Hi All
I'd be grateful for some ideas on my latest possible project.
I've been asked at my sailing club whether it would be possible to have
a winch to pull boats up the slipway. The boats in question are patrol
boats with outboard motors and probably weigh about 500 pounds. The
slipway is about 1 in 8 at its steepest part and it normally takes three
people to pull the boats up the slipway.
There is no mains electricity available and it needs to be mobile as
there are two slipways. I've considered a winch as used on 4*4s but the
recovery rate is tiny and the current demand in huge.
I have been wondering about a petrol powered winch - my initial thoughts
were to use a cylinder lawn mower - remove the blades and modify the
roller to reduce the diameter and use that as the winch. I'm not sure
whether that would be sufficiently low geared for the steepest bits.
The ideal solution would probably have more than one gear.
Is this a completely stupid idea - are there any better ideas out there
- like a motor mover of some sort - that won't take loads of time and
material.
Russell
Reply to
Russell
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The fishermen at Cadgwith on the Lizard Peninsula have long had an internal combustion-powered winch to haul their craft up the beach and it is housed in one of the stone sheds adjacent to the beach (at least this was the case in 1993 when I was last there)
The early LandRovers had an engine-powered winch. This wouldalso solve the problem of transporting the winch itself to where it was needed.
Reply to
Phil O. Sopher
How about a quad bike? The ones that are sold for agricultural use are fitted with a tow ball & you may be able to pick up a s/h one for not a lot.
Regards, Tony
Reply to
Tony Jeffree
When I was involved in lauching and recovering a 4.8 m. RIB, probably weighing 700 kg. gross on a similar gradient we did it with a rope attached to the towing vehicle to avoid immersing the car. Once up the slipway the trailor would be attached to the towball as normal. The method requires a jockey wheel at the front of the trailor and a couple of people to steer it. It easy, cheap and rapid.
Cliff Coggin.
Reply to
Cliff Coggin
Take a look at mile marker or similar hydralic winches. The rating is overkill, but you can run a power steering pump off a 3.5Hp lawnmower engine to drive one, and itll run all day long (as long as you remember the petrol...)
Hydralic winches somtime come up at witham-sv.com ex mod.
Dave
Reply to
small.planes
You mean something like this?
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Reply to
Dave Baker
As Gareth posted, the standard "fix" in the fishing industry is a car engine on a mount, generally in some sort of shed/hut.
If you wander along any beach where the fishing boats are launched and landed on the shore you will see them.
Often as not they've got the engine and gear box, complete with the gear lever!, just as if the whole lump has been lifted from the car. How the drive is coupled to the winch varies- at least one I saw had a "chopped down" prop shaft. It looked like on of the Ford ones (Mr2 Escort vintage but may be not an Escort) which had a "mid" UJ. The winch drum was fabricated around the short propshaft section. All contained in an angle iron "cage".
Loads of rust, oil, smoke etc. but it dragged a big boat up the shingle beach like it was a roller skate on a mirror.
Brian
Reply to
Brian Reay
or an old scrap car on bricks, and wrap the cable round one of the wheels (sans tyre)? Might have to weld up the diff.
Reply to
bigegg
Excellent value - to try to price it I 'added to cart' and it came up as £0.00 plus vat though!
AWEM
Reply to
Andrew Mawson
OOH! I'll have two then!
Bob
Reply to
Bob Minchin
Sailplane club did launches with a rusted truck mounted on a frame and the wire cable wound around one of the wheel drums.
Might be too fast for boat hauling.
Reply to
_
The cylinder mower might work. You could use ropes or chains around the front roller to secure it, then make some feet to hold the rear roller off the ground. But some mowers have a belt-driven rear roller, which is a bad idea as the belt can slip. You might also have a problem getting the rope between the rear roller and chassis. But with a mower you do get the clutch included. Pick the right mower and it could probably pull the boat without reducing the diameter of the rear roller. But it'd be fast, and it'd also be a bit of a shame to do that to a good mower :-).
Do post some pictures if you build one.
Best wishes,
Chris
Reply to
Christopher Tidy
Thanks for all the suggestions - there's some food for thought there. Clearly throwing money at it is the easy solution.
A quadbike or a car would be easy - the car would take space and the quadbike would be used as a toy until someone broke it.
The petrol powered winch link claimed a 125:1 reduction using a 50cc size motor and a 2.5" barrel. That's interesting as it gives some parameters for my original idea. I have an old Suffolk Punch with a similar sized engine and I estimate about a 40:1 reduction to the rear roller which is about 7" diameter. As Chris points out this has all the controls nicely to hand but to match the commercial winches pulling power I need more gearing. If I reduced the roller diameter to 1.25" then I might get a pull something like 1300 lbs - probably enough to break the mower into pieces.
I'll be giving this some more thought but I'd welcome any more suggestions or comments.
Russell
Reply to
Russell
Easiest way is to start from expected torque per litre from an engine. For a 4 stroke in a very mild state of tune like a lawnmower that's probably about 40 to 50 ft lbs per litre. A 2 valve car engine would be more like 50 to 60. So for a 50cc engine we can assume perhaps 2 to 2.5 ft lbs.
Call it 2.25 and add a 40:1 reduction ratio. That's 90 ft lbs which would give a pull of 540 lbs at a 2 inch radius. You have a 500 lb boat coming up a maybe 1 in 10 slope. The required pull is unlikely to be more than 200 lbs or so depending on coefficient of friction. It should actually be much less but you can measure it with a spring balance. You can probably use a 4 inch radius for a 270 lb pull. About the same size as your rear roller anyway which would pull over 300 lbs.
Now we can move to bhp and pull speed. One bhp is 33000 ft lbs per minute. 2.25 ft lbs at 3000 rpm is 2.25 x 3000/5252 = 1.28 bhp or 42412 ft lbs per minute. That can move a 200 lb pull 212 ft per minute = 2.4 mph. It'll whizz your boat up a slipway in less than 30 seconds.
Measure your actual reduction ratio and pull force required and you can work out the rest very simply by following the maths above.
Reply to
Dave Baker
The simplest idea might be to acquire an old kart. (Go kart). Many of these are chucked away when teh chassis gets fatigued but all you want is the backend.
You have the engine with a chain drive to an axle, with all the gearing you could want (At least 9 to 1 easily available, 80 to 1 with a little welding to make an intermediate shaft)
Simply take the tyre off one wheel, wrap the boat rope round the capstan shape of the rim. With up to 28 hp available from a 125cc or 8hp from a Cadet 60CC you should have no problem getting the boats out of the water. You could even get a Honda GX160 as used on your local hire and drive.
And if you want to spend a little money, kart engines come with water cooling and electric start and centrifugal clutch.
And if you use the system as a capstan, not a winch, you have all the control you could want.
Robin
Reply to
rsss
modify the
around the
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mower :-).
pulling
engine. For a
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I'd want to look carefully how the roller and its bearings are secured to the frame - it wasn't originally designed for a load greater than the weight of the mower plus a margin, whereas your application has a darn great boat hanging on it !
AWEM
Reply to
Andrew Mawson
Russell pretended :
Very much heavier than that, but a little less steep - I pull the caravan back up the drive with a hand winch and it is quick plus easy.
They sell the winches at car accessory shops and on ebay, around £10 to £20, with a ratchet to stop them slipping back if you stop cranking.
I have the winch bolted onto a flat plate welded to a short scaffold pole. The pole drops into a suitable hole at the top of the drive, leaving the crank at a good working height.
Reply to
Harry Bloomfield

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