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  #1  
Old 05-25-2006, 08:15 AM
MikeJohns MikeJohns is offline
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Windlass specification issues

What do others do when it comes to the design of the anchoring system?

Having just tried to specify 3 choices of windlass to the builder (for a 50 foot 25 tonne vessel ) I am surprised at the poor responses to specific engineering questions from the manufacturers. For example output Torque and shaft diameter are not available data .

All they will give us is chain speed, recommended working load, and motor power rating. I think they worry that we will calculate something and find their machine lacking..........I would like to know the factor of safety which I suspect is very close to 1.

Requests for technical info seem to go directly to marketing who simply email you the pretty charts showing models and recommended boat sizes.

From experience there are models that proved to be idiot-proof and others that bent shafts and fractured bearings at the slightest provocation, problem is that that many current models are new on the market and I'd like to specify something I trusted.
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Old 05-25-2006, 08:39 AM
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marshmat marshmat is offline
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Usually when I come across a company that passes technical requests off to marketing, I'll reply with something like "look, I want these numbers and I know what they mean, and if you aren't willing to provide them, that's a pretty good indicator that you're selling a piece of crap". Makes it a bit more difficult when the whole industry does it though. A windlass maker should have these data- and if they don't have it at all (as opposed to just being unwilling to provide it), they're probably just slapping pretty housings on crappy motors.
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Old 05-25-2006, 07:00 PM
MikeJohns MikeJohns is offline
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Matt
unfortunately the days of overengineered life-time products seems to have passed by. The approach these days seems to be make it "just" strong enough and don't give em enough information so they can say our product was deficient. Most Windlasses are expensive enough too.

Cheers
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Old 05-25-2006, 07:04 PM
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marshmat marshmat is offline
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Quote:
Originally Posted by MikeJohns
Matt
unfortunately the days of overengineered life-time products seems to have passed by. The approach these days seems to be make it "just" strong enough and don't give em enough information so they can say our product was deficient. Most Windlasses are expensive enough too.

Cheers
Sadly, this seems to be the case in a lot of fields. If it wears out after a few years, you'll buy another one, the economy keeps rolling. Whatever happened to "durable goods"?.....
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Old 05-25-2006, 08:48 PM
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Willallison Willallison is offline
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Quote:
Originally Posted by marshmat
Usually when I come across a company that passes technical requests off to marketing, I'll reply with something like "look, I want these numbers and I know what they mean, and if you aren't willing to provide them, that's a pretty good indicator that you're selling a piece of crap". Makes it a bit more difficult when the whole industry does it though. A windlass maker should have these data- and if they don't have it at all (as opposed to just being unwilling to provide it), they're probably just slapping pretty housings on crappy motors.

It's also a little difficult to do this if the manufacturer is just down the road and you want to kepp good relations with them....
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Old 05-26-2006, 05:55 AM
FAST FRED FAST FRED is offline
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Location: Conn in summers , Ortona FL in winter , with big dock & room for O'nite stop .
From what I have installed the Hydraulic are 1000% better than any brand of electric.

Yes, I know a complete Hyd system is an extra layer of complexity , but if used for steering , auto pilot ,bow thruster , windlass and small boat handeling it pays in the long run.

Lighthouse makes high quality Hyd stiuff that looks like eye candy!

And is Pri$ed accordingly,but you only get what you pay for,

FAST FRED
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Old 05-26-2006, 08:54 AM
Tim B Tim B is offline
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you could always walk into their offices and refuse to leave until they've told you the numbers you want.... that usually works.

Tim B.
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Old 05-26-2006, 11:23 PM
MikeJohns MikeJohns is offline
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Quote:
Originally Posted by Tim B
you could always walk into their offices and refuse to leave until they've told you the numbers you want.... that usually works.

Tim B.
Tim I tried that once

I stood in the office for 10 minutes playing with the sample machines before a harrassed secretary appeared and took my questions back into the factory .......to be told that the engineer who designed a particualr bit of production gear had gone so no-one could help until the replacement guy got copies of all the drawings back from the various fabricators. ....


Fred
I agree hydraulic is far more reliable in the long run and I wouldn't specify anything else for a work boat, trouble is owners have their own ideas too and there is a prejudice with yachties against hydraulics as messy and complicated. Many yachts do not have the space for much extra gear belted of the engine either.

Cheers
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Old 05-27-2006, 05:38 AM
FAST FRED FAST FRED is offline
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Location: Conn in summers , Ortona FL in winter , with big dock & room for O'nite stop .
"(for a 50 foot 25 tonne vessel ) "

Hard to believe there is no room for a belted hyd pump.

As a builder of course you're stuck with the misconceptions and fantastically dumb ideas of the "owners".

But there is always a chance you can 'splain them enough to make a better choice.

But then I'm an Optomist.

Was at City Island NY ,where a fine steel cutter 60 ft "Dolphjn", had finished SECOND circumnavigation with only hubby & wife crew, was being assulted by new "owner" who was "going to make it a cruising boat".

He had read an issue of Cruising Word , (a magazine that didnt even have a Tech editor) , picked up the sledge and went to "work".

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Old 06-21-2006, 07:49 AM
Theodora Theodora is offline
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If I were you, I'd go to either Muir or Maxwell (Muir have better pricing), take an oversized windlass for your displacement and ask for a three year warranty.
Unless you are planning on pulling your boat under against a stuck anchor, I think their equipment will do the job.
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Old 06-21-2006, 07:05 PM
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Willallison Willallison is offline
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Hmm... Muir ... ever heard of them Mike?
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  #12  
Old 10-14-2006, 04:31 PM
M&M Ovenden M&M Ovenden is offline
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Hi Mike,

I realize this thread is a bit old, but I was wondering what you have come up with ? Our boat is ~50ft and 24 tons, so I'm curious what choices you & the owner made. We are starting to think about ground tackle and windlass selection.

So far I've been favouring the lighthouse 1501, as it has a very powerful manual mode. To me this means the shafts / bearings are much stronger that what is needed for the motor torque. I've also been kicking around the 12V vs 24V question. Here's an email that I recieved from Lighthouse.


"Because of the type of motor we use the 12VDC through 32VDC motors have the
same efficiency rating. So the voltage option is up to you.

You describe the vessel as 50' LOD and approx 24 tons disp. Ground tackle
should be around 500 lbs for 3/8 TH G4 chain and approx 70 to 110 lbs for the anchor. Chain length would be 275'. I would not consider 7/l6" for the vessel you describe. This would constitute your primary anchor rode, the secondary can be made of 3/4" twisted Nylon and 50' of 3/8" chain.

The above would be our recomendation. The 1501 series will accomodate this ground tackle no need to go to the 3002 series machine. If you have a bow sprit we also have adapters for this application available they are made to order for each vessel. There is special tooling available from Lighthouse
on a loan basis for drilling the pattern holes for motor, hawse pipes etc,.."


Any suggestion/comments are most welcomed.

Cheers,
Mark Ovenden
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  #13  
Old 10-15-2006, 01:00 AM
MikeJohns MikeJohns is offline
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Mark

They ended up with a Lofrans Falkon. Runs in a gear oil bath rather than grease packed and is very well engineered (Italian).

Muirs and I think Maxwell ran about equal spec some models have a thin electroplated steel base plate covering the machinery cavity that is not a good design feature. There is also some appearance issue here, some look like a Sumo wrestler others are more elegant.

Lofrans have a 240volt ac motor option for 240volt systems, but otherwise I'd stick to 24v. You can buy high efficiency 12v windlass motors only to lose the energy to heat in the supply cable (at 2X the current to 24 v).


I have not met lighthouse windlasses. Looking at the website they look robust, I would check what a “Linear power” motor is, if it needs fancy electronics go for a simple motor any day. I feel that efficiency of windlass motors is a non-issue. Reliability is everything.


High test (higher tensile) (HT) chain is good and you can use the next size down and still go up in strength. Make sure that a Gypsy exists for any type of chain that you may want to use. Muirs for example offer all, HT- Proof -BBB this can be a very good feature.

Chain is self handling and very convenient and non-chafing, but nylon rode is a good option too, if you use a lot of rope based anchor systems then the capstan accessibility/ease of use becomes important to assess.

Have a read of the following website re nylon and chain
http://alain.fraysse.free.fr/sail/sail.htm

All the best
Mike
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  #14  
Old 10-15-2006, 01:12 AM
MikeJohns MikeJohns is offline
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Quote:
Originally Posted by Willallison
Hmm... Muir ... ever heard of them Mike?
Will
Yes I think they are a quality engineering product, they have a growing market reputaion especially in the large expensive pleasure-boats.

Like any manufacturer they have been let down in the past with out-sourcing component quality at times but they do stand by their products. They seem to have good management these days and will certainly be here for the long haul.

With a design it is prudent to give the builder 2 or even 3 equivalent specs, items like windlasses and Engines can be out of stock and 3 months to delivery at times.

Cheers
Mike
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Old 10-15-2006, 06:34 AM
FAST FRED FAST FRED is offline
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Location: Conn in summers , Ortona FL in winter , with big dock & room for O'nite stop .
"I feel that efficiency of windlass motors is a non-issue. Reliability is everything."

In that case the IDEAL made in the USA would be first choice.

Last time I looked the windlass motors were Chevrolet starter motors.

Avilable world wide rebuilt for $20 to $50 , no waiting.

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