Help understanding windlass specs

[Little Dorrit]

I am researching 12 Volt options with an 8mm gypsy for a 800 w- 1000 w motor, low profile windlass.

What are the considerations when considering Motor size and maximum pull.

I noticed that the maxwell RC8 has a maximum pull of 600 Kg against the Lofrans X2 of 1000 Kg but with similar motor and current draw, which goes against my instincts.

I was wondering if there is any reason for this difference and what other factors might be relevant when deciding which option is best?

 

[Boathook]

I suspect that the retrieval speed is lower for the smaller powered one, so through the gearbox more pull can be generated. In the end though you are limited by what will fit in space you have for the windlass. When deciding on the space don't forget to allow for fitting the bolts and wiring.

 

[noelex]

The wattage of the windlass motor is a very nominal number so it is not a good guide to the likely power of the windlass, especially as the gearing and other factors also need to be considered.

As an example, the Maxwell 3500lb windlass has a 1200w motor but the less powerful 2500lb windlass has a 1500w motor.

To understand the difficulty manufacturers have when listing a single figure that reflects the power of these motors, consider my own windlass as an example. The nominal rating is 2000w, but if you look at the more detailed specifications at the maximum rated windlass pull the motor is drawing over 9000w. If the windlass manufacturer listed the 9000w figure it would likely put off potential buyers, but all windlass motors will draw considerably more than their nominal rating under high load.

 

[Martin_J]

I noticed that the maxwell RC8 has a maximum pull of 600 Kg against the Lofrans X2 of 1000 Kg but with similar motor and current draw, which goes against my instincts.

As Boathook mentioned - By different gearing, if the windlass is geared to turn slower, it will be able to lift a larger maximum load.

From the specs, it looks like the Rc8 will pull in at 32m/min at normal working load whereas the X2 is quoted as 20m/min at working load. Could be why the X2 is quoted as having a larger maximum pull. Max line speed is only shown for Lofrans (40m/min) so might be hard to compare that.

TBH - I think how it fits into the space you have both above and below decks and maybe availability of spares now becomes more important.. So long as the max pull is enough to lift all your chain and anchor (should you accidentally release it all in deep water) then you'd be happy with either. At about 1.5kg per meter for 8mm chain, I'm sure either will be enough.

I went through same type of conundrum recently when replacing a twenty year old Lofrans manual with an electric windlass. Happy with my choice although I think I'd have been happy with any new electric windlass

 

[Neeves]

We replaced a Muir Atlantic 1000 with the Maxwell RC 8. Ours takes a 6mm chain (its designated a RC 6-8 or RC 8-6) - but we were down sizing from an 8mm chain. It was the same yacht so same possible loads so we needed the RC8. Opted for 1000w motor as we don't think you should compromise on grunt. We did not want the capstan as our windlass is located below deck and we have an electric winch and mast based winches.

Maxwell offered a superb service ,they discussed with me what we were doing, down sizing, and came up with what we have, you should get the same service from Vetus - world wide.

We did our own installation, easy. Our unit came with solenoid and relay but no switches. They do supply switches - you need to option what you want, foot (at the bow) or toggle (at the helm) (or both).

The RC 8 has manual retrieval system which demands inserting a supplied, short handled, winch handle into the gypsy except a standard winch hamdle will not fit as there is a dome nut in the orifice - so don't lose the one supplied. If you want a bit more height for manual retrieval you can buy a 'rod' that fits into the top of the gyspy and accepts the winch handle, it lifts the handle about 150mm higher, reduces bending down so much (its sort of like an extender in a socket set). As Martin defines the electric retrieval speed is exceptional, don't worry about what happens if you need to retrieve in a hurry.

Servicing is simply, there is a quick release and you can remove the gearbox easily and the gear box has a window so that you can inspect the oil in the gearbox, for both volume and quality. The motor can be swung to any angle, well almost, - just plan to have the motor opposite, away from the fall of the chain. All these motors are supplied with mild steel casing (they may all come from the same Italian factory) I suggest you coat it with the stuff used in the UK to seal the underside of cars to protect them from the salt on the roads in winter .... the name of which I forget (salt on roads is not a big thing in Australia).

Maxwell have a nice gypsy that will accept chain and rope..





This is part of our installation, note the motor is as far away from the fall of the chain as possible. That's 75m of 6mm chain.



Just to the right of the fall of the chain you will see a little wire ring, that's one end of the circlip you remove and can then remove the whole gearbox - dead easy.

Note the various bolts to hold the whole thing together, they are all stainless - have something handy, if you are installing yourself to ensure there is no corrosion of the bolts.

If you would like more photographs of the RC8 unit, in pieces and assembled - I have them but on another computer (excuse me I'm both human and lazy - if you don't need them I'll keep for..... later).

Problems none - we have had our windlass for 3 years now and expect it to last, at least, another 20 years.

Regrets - only that we did not have a Maxwell from the outset.

Good luck

Take care, stay safe

Jonathan

edit The 1000 (and the 600kg) is a bit of a phorphy - you will never, ever experience that tension. A 8mmG40 chain has a WLL of 1,000kg -why do you need that ability in a windlass? You should not be subjecting the windlass to anything like that tension (it is possible the windlass will pull out of the deck prior). I you read the instructions for any windlass to will say don't use the windlass to pull the yacht to the anchor, motor forward - if you do that then the tension possible is a low few hundred to break the anchor out vertically.

J

 

[Little Dorrit]

We replaced a Muir Atlantic 1000 with the Maxwell RC 8. Ours takes a 6mm chain (its designated a RC 6-8 or RC 8-6) - but we were down sizing from an 8mm chain. It was the same yacht so same possible loads so we needed the RC8. Opted for 1000w motor as we don't think you should compromise on grunt. We did not want the capstan as our windlass is located below deck and we have an electric winch and mast based winches.

Maxwell offered a superb service ,they discussed with me what we were doing, down sizing, and came up with what we have, you should get the same service from Vetus - world wide.

We did our own installation, easy. Our unit came with solenoid and relay but no switches. They do supply switches - you need to option what you want, foot (at the bow) or toggle (at the helm) (or both).

The RC 8 has manual retrieval system which demands inserting a supplied, short handled, winch handle into the gypsy except a standard winch hamdle will not fit as there is a dome nut in the orifice - so don't lose the one supplied. If you want a bit more height for manual retrieval you can buy a 'rod' that fits into the top of the gyspy and accepts the winch handle, it lifts the handle about 150mm higher, reduces bending down so much (its sort of like an extender in a socket set). As Martin defines the electric retrieval speed is exceptional, don't worry about what happens if you need to retrieve in a hurry.

Servicing is simply, there is a quick release and you can remove the gearbox easily and the gear box has a window so that you can inspect the oil in the gearbox, for both volume and quality. The motor can be swung to any angle, well almost, - just plan to have the motor opposite, away from the fall of the chain. All these motors are supplied with mild steel casing (they may all come from the same Italian factory) I suggest you coat it with the stuff used in the UK to seal the underside of cars to protect them from the salt on the roads in winter .... the name of which I forget (salt on roads is not a big thing in Australia).

Maxwell have a nice gypsy that will accept chain and rope..

View attachment 119336



This is part of our installation, note the motor is as far away from the fall of the chain as possible. That's 75m of 6mm chain.

View attachment 119337

Just to the right of the fall of the chain you will see a little wire ring, that's one end of the circlip you remove and can then remove the whole gearbox - dead easy.

Note the various bolts to hold the whole thing together, they are all stainless - have something handy, if you are installing yourself to ensure there is no corrosion of the bolts.

If you would like more photographs of the RC8 unit, in pieces and assembled - I have them but on another computer (excuse me I'm both human and lazy - if you don't need them I'll keep for..... later).

Problems none - we have had our windlass for 3 years now and expect it to last, at least, another 20 years.

Regrets - only that we did not have a Maxwell from the outset.

Good luck

Take care, stay safe

Jonathan

edit The 1000 (and the 600kg) is a bit of a phorphy - you will never, ever experience that tension. A 8mmG40 chain has a WLL of 1,000kg -why do you need that ability in a windlass? You should not be subjecting the windlass to anything like that tension (it is possible the windlass will pull out of the deck prior). I you read the instructions for any windlass to will say don't use the windlass to pull the yacht to the anchor, motor forward - if you do that then the tension possible is a low few hundred to break the anchor out vertically.

J

Thanks, Johnathon for your reply, comprehensive as usual.

I think if my budget allows the Maxwell is going to be my choice.

Regarding your final comment I think the thing to do is imagine the windlass is just another crew member so making it as easy as possible for it would be the logical thing to do. My move to an electric windlass is a result of too many early starts single handed in tight anchorages where retrieval of the anchor can be stressful.

P.s Thanks also for all the great information (controversial or not) you post here regarding dare I as the word... 'anchors'!

 

[Little Dorrit]

As Boathook mentioned - By different gearing, if the windlass is geared to turn slower, it will be able to lift a larger maximum load.

From the specs, it looks like the Rc8 will pull in at 32m/min at normal working load whereas the X2 is quoted as 20m/min at working load. Could be why the X2 is quoted as having a larger maximum pull. Max line speed is only shown for Lofrans (40m/min) so might be hard to compare that.

TBH - I think how it fits into the space you have both above and below decks and maybe availability of spares now becomes more important.. So long as the max pull is enough to lift all your chain and anchor (should you accidentally release it all in deep water) then you'd be happy with either. At about 1.5kg per meter for 8mm chain, I'm sure either will be enough.

I went through same type of conundrum recently when replacing a twenty year old Lofrans manual with an electric windlass. Happy with my choice although I think I'd have been happy with any new electric windlass

Thanks, yes it clearly depends on the motor gearing what the line speed and pull would be, I must have not been thinking clearly when I made the post although there have been some good responses which have highlighted other considerations.

 

[Neeves]

I must have not been thinking clearly when I made the post although there have been some good responses which have highlighted other considerations.

That's what the forum is for - Much of the time we just need someone to speak to and bounce ideas off.

Our Maxwell is lovely bit of kit, all bright and shiny, though that had nothing to do with our choice But no-one sees it being housed under the deck.

Do remember, if you use a snubber, to use a back up so if the snubber fails (you chose the snubber for elesticity not strength) you don't suddenly transfer a snatch load to the windlass. You can buy chain locks, I know Lewmar have them (and maybe Maxwell) but you can simply use a short strop tied to a strong point with a hook on it. We do the latter and it holds the anchor secure when on passage (or have I said all this already ).

Windlass last forever, well almost, but should be serviced annually, check the gear box oil and grease the shaft, simple stuff (but few do it). So when you install think of where the motor and fall of chain will be but also consider you will want to service so make the motor cables such that you can lift the gear box and motor out easily. You can unbolt the motor but bolting it back together inside a locker is a bit of a contortionists struggle so taking out in one piece is easier (with the way the Maxwell disassembles) - which may be as easy as any other, - just have enough cable. When a professional installs he will make it convenient to install and have no interest in the thereafter (which might be why people don't service - too difficult to take apart).

My fetish means I look at these things and one of the worst, on a new yacht at a boat show, was a motor installed with the chain falling and actually rubbing on the motor casing. All neat and compact - I guess a new motor needed quite quickly.

Jonathan

If my ideas are controversial I hope I offer data to underpin what I am saying. But controversial ideas make people think and question the norm. Our ideas are based on skills developed over decades (for anchors maybe since the introduction of the CQR). Since when we have introduced nylon, relatively cheap electric windlass, HT steel chains, HT steel and a large cross section of new designs - yet Antarctic Pilot quotes usage today of 30/40 years ago, based on setting a CQR, that has remained unchanged despite these changes.

I'm all for outside the box ideas being aired - and here seems a good place.

Controversy also helps those who are bored and keeps their brain active - even if they whinge about anchor threads or the length of posts - neither stop them contributing - funny old world

Take care, stay safe

 

[Neeves]

I had a check this morning

Our Maxwell is an RC8-6 (so the RC8 with a 6mm gypsy). Maxwell do make an RC6 but it is completely different engineering and from memory has the motor mounted vertically - so its quite a tall unit and an in line drive. I suspect it does not take a big motor - or it would be enormous, or unmanageably tall.

I don't know but I beleive the RC 8 is designed round using 8mm chain, and all that infers in terms of possible loads. Which is why we have an RC8-6 having downsized to 6mm chain but still enjoying the same possible loads of 8mm chain. The RC 6 will then be designed round the smaller loads expected from conventional G30/40 6mm chain which would suit smaller loads as found on smaller vessels.

If your yacht is borderline between use of 10mm and 8mm chain is might merit looking at an RC10-8 (but that might be more expensive) - just something to throw in the melting pot. Having said that many yachts appear to use excessively and unnecessarily larger chain and given the absence of chain failure 'we' might have gone too far in our search for high safety factors and catenary at the expense of yacht performance (and wallets).

Jonathan

 

[Little Dorrit]

That's what the forum is for - Much of the time we just need someone to speak to and bounce ideas off.

Our Maxwell is lovely bit of kit, all bright and shiny, though that had nothing to do with our choice But no-one sees it being housed under the deck.

Do remember, if you use a snubber, to use a back up so if the snubber fails (you chose the snubber for elesticity not strength) you don't suddenly transfer a snatch load to the windlass. You can buy chain locks, I know Lewmar have them (and maybe Maxwell) but you can simply use a short strop tied to a strong point with a hook on it. We do the latter and it holds the anchor secure when on passage (or have I said all this already ).

Windlass last forever, well almost, but should be serviced annually, check the gear box oil and grease the shaft, simple stuff (but few do it). So when you install think of where the motor and fall of chain will be but also consider you will want to service so make the motor cables such that you can lift the gear box and motor out easily. You can unbolt the motor but bolting it back together inside a locker is a bit of a contortionists struggle so taking out in one piece is easier (with the way the Maxwell disassembles) - which may be as easy as any other, - just have enough cable. When a professional installs he will make it convenient to install and have no interest in the thereafter (which might be why people don't service - too difficult to take apart).

My fetish means I look at these things and one of the worst, on a new yacht at a boat show, was a motor installed with the chain falling and actually rubbing on the motor casing. All neat and compact - I guess a new motor needed quite quickly.

Jonathan

If my ideas are controversial I hope I offer data to underpin what I am saying. But controversial ideas make people think and question the norm. Our ideas are based on skills developed over decades (for anchors maybe since the introduction of the CQR). Since when we have introduced nylon, relatively cheap electric windlass, HT steel chains, HT steel and a large cross section of new designs - yet Antarctic Pilot quotes usage today of 30/40 years ago, based on setting a CQR, that has remained unchanged despite these changes.

I'm all for outside the box ideas being aired - and here seems a good place.

Controversy also helps those who are bored and keeps their brain active - even if they whinge about anchor threads or the length of posts - neither stop them contributing - funny old world

Take care, stay safe

Thanks, for the advice. I'll download the installation instructions and have a look. I think when I refer to your posts being controversial I simply mean against historically accepted ideas. New theories don't remain controversial for long but usually challenging the thinking that is we were brought up with such as upsizing anchors or chain will raise a few eyebrows!