another idiot with mad ideas, new boat build

I think depending which version of the kit you buy depends on what hull type you get.
I am waiting for more details coming through from the seller.

I cant comment on the jet drives. Seems a bit fast for me. The old combat support boats i used to drive had jet drives, and wouldn't get to that speed and were a lot lighter...
 
Robg71 said:
Question.
Hydraulics.... Yes or no
Am i better off going to 24v or hydraulics... Is it possible to run a pto from a generator?
Am i best just running the generator to power a hydraulic pump.?
Am i best of forgetting hydraulics full stop... Will i regret that later....
Possible uses, bow/stern thrusters. Anchor capstan/windlass.
Click to expand...

Another thing to consider now is the resale of the boat, the day will come you'll want to sell the boat and if certain systems will help that sale or help achieve a better value then I would put them on.
 
Im currently looking at drive chain components, and the main boaty side of life.
I went aft in my current boat, down in to the cabin, and it sounds like a meat grinder on full chat. which led me to think of the props, shafts et al.
would you fit cv joints to transfer load to the hull.
personally I think I will. any reasons why not.
looking at a system from GKN.
 
QUOTE=Robg71;4213627]Question.
Hydraulics.... Yes or no
Am i better off going to 24v or hydraulics... Is it possible to run a pto from a generator?
Am i best just running the generator to power a hydraulic pump.?
Am i best of forgetting hydraulics full stop... Will i regret that later....
Possible uses, bow/stern thrusters. Anchor capstan/windlass.[/QUOTE]

Hi Rob,

You might want to have a look at this type of system http://www.phoenixmarinesolutions.co.uk/Central_Hydraulic_System if you want thrusters, winches steering and maybe stablizers. They can be powered by the main engine, generator (PTO or Electrical) or even battery powered.

If you want any information on generators, drop me a PM.

Anthony
 
Hmmm, are you offering me advice or sales.
Advice is good. Sales is good too, but not yet.

So far I prefer the 24volt option
Less equipment, no oil to leak. No mess, no having to run a genset for 1/2 an hour warm up/ warm down for thirty seconds use. What it doesn't give me is expansion options.
Can they be driven from battery power. (I'm certain they could be)
Why would I want to fit hydraulics????
 
Advice only, just making you aware of different options.

Ultimately you need to decide what options you want to fit, If it just a bow thruster and steering then I agree DC units will be best options, but if you want stablizers and the option to add crane or winches then maybe you should investigate a hydraulic system, as I do not see the point in generating power to drive a AC motor to drive a pump that the generator could have driven directly and the cost is less.

Also two or three boat builders have switched from driving the hydraulics with AC motors to direct drive as the motor noise can be annoying while at anchor.

Normally a main engine pump takes care of the hydraulic's while underway and the generator can be used while at anchor for Stablizers or crane etc.

But Marine power generation is my area, so if you need advise (not sales) feel free to ask away.

Anthony.
 
Thats great, thank you.

for power gen, i have looked at the victron range of electronics, amongst others. the quattro sysytem, seems to fit the bill.
Northern Lights gen sets, as the reports I have read of these are very good.

Is a fifty foot boat still a bit on the small size for stabs. I beleive the systems are still expensive, but does not mean i can not build the boat around a system for future fitment.
 
I know nothing about power boats, but those pics look to me like a proper small ship.
I just can't get on with the aesthetics of modern Mobos.

Dont like the second version with the plumb bow.

Bear in mind this opinion is given by a person who sails a boat where the accommodation is smaller and less luxurious than a Mobos crew quarters.
 
Robg71 said:
ok, been as I am half way to being certified, whats your take on these.
please, non of the don't do it, you will never finish it, it will be ****.... just genuine pros and cons.

I think its stunning...

1023-184-640-g6j.jpg


1023-195-640-t9t.jpg


1023-190-640-h8d.jpg


being as I am about to buy its engines... :)
Click to expand...

It's gorgeous and I can only dream of what it would be like to cruise around in one of those.
 
Does anybody have any plus or minus points about dc generators, running to heavy duty inverters, as opposed to an AC genset.

Any in use or first hand experience.
Am looking at suitability of dc brushless motors for driving things like compressors etc...
Seems it could be a more efficient method for use on boats...

Cheers
Rob
 
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Robg71 said:
Does anybody have any plus or minus points about dc generators, running to heavy duty inverters, as opposed to an AC genset.

Any in use or first hand experience.
Am looking at suitability of dc brushless motors for driving things like compressors etc...
Seems it could be a more efficient method for use on boats...

Cheers
Rob
Click to expand...

We had a DC genny on the home farm, and a mechanical commutator to convert to AC. It was belt driven with a single cylinder Lister diesel, all the lights used to flicker....... those were the days.

Make sure you don't get a shock, it'll be your last.
 
Ah, lister diesels. I fondly remember scraping knuckles etc starting those things by hand.

Yes, always a downside with dc is that. I had a 440v ac hit once. That hurt... To say the least.

Im not 100% certain of the dc gen idea, just feeling it out.
 
Robg71 said:
Am looking at suitability of dc brushless motors for driving things like compressors etc...
Seems it could be a more efficient method for use on boats...
Click to expand...
On paper, yes, but I've never seen any installations so far.
I suppose there must be a reason, but I couldn't get my head round it, so far.
I'd also be interested to hear about any hands on experiences.
 
Robg71 said:
Does anybody have any plus or minus points about dc generators, running to heavy duty inverters, as opposed to an AC genset.

Any in use or first hand experience.
Am looking at suitability of dc brushless motors for driving things like compressors etc...
Seems it could be a more efficient method for use on boats...

Cheers
Rob
Click to expand...

Have you come across the book "Energy Unlimited" from Victron? Lots of interesting stuff, especially about DC generators. Even a little section on compressors. Free download from http://www.victronenergy.com/upload/documents/Book%20-%20Energy%20Unlimited%20-%20rev%2009%20-%20EN.pdf
 
Hi Rob,as I've only just picked up on your thread I hope you don't mind if I offer some input about your planned project and,as I haven't had time to go through all the replies yet I am assuming that nobody else has already raised the same points.
Firstly,I have a 43 foot grp semi-d with 2x425hp qsb's,fully loaded it weighs 16-17 tons.It's top speed is around 24knots downhill on a good day. So,what you appear to be considering is a steel boat which I reckon will be around 22 tons empty or nearer 25 tons all up with smaller engines and expecting a near similar performance? Don't get me wrong,it looks a really handsome design (unlike much of the typically angular stuff being turned out in Holland) and the Cummins are great engines .....but,a heavy steel planing boat ??? I spend a lot of time in Holland and last year I met the guy who has the patent on the design for small steel planing boats.He told me how he had spent years working out how to make the idea work efficiently and then in conjunction with Tryvia Yachts,a small Dutch builder producing 4-5 boats a year,had produced a 13 metre boat that would plane with only one engine. It's called the 1300GT and you can see it on www.tryviajachten.com and then clicking on Snelvarend. It weighs 11 tons empty but,what they don't tell you on the website is that it is only the hull that is steel (thin section at that) and the top sides are aluminium. The use of aluminium topsides is of course not only to keep down the overall weight but,just as importantly,to keep down the centre of gravity,especially through higher speed manoeuvering. Lighter weight grp boats lean in during high speed turns whereas heavy steel ones lean out in similar fashion to warships etc. That aside,I would have to question the straight line performance of such a beast in comparison to my own boat which needs to reach around 15 knots to get over the hump and then will fall off the plane at anything below about 13.5 knots. Then there is the fuel consumption to consider. At typical pootling speeds of 7-9 knots we can get 2-3 mpg but,once on the plane ,even 15 knots returns about 0.7 mpg and flat out is about 0.5. Worse still,Cummins also supply a full diagnostic set up so you can read how much money each burst of speed is costing. I doubt you will get much or any real planing performance anyway but,if you do you most certainly won't like the cost. So,assuming you haven't already commited to buying the casco yet,why not consider something similar in aluminium,which would give you the same amount of fun completing its build but probably far more fun running it afterwards. There are plenty of casco builders in Holland who will happily produce a similar design to someone elses in aluminium and you will find in these hard times that their prices are extremely negotiable. Incidentally,just some weight comparison data if it's of any help:-
Weight per cu.ft.
Steel - 490 lbs.
Aluminium - 168 lbs.
GRP - 100 lbs. approx.depending upon lay-up thickness.
Just one more thing maybe to consider - when and if you come to sell it on,have you any idea how many potential buyers there would be for your pride and joy?
Sorry,didn't mean to piss on your parade - I wish you well whichever direction you go.
 
You now know as much as me.....
Weight of the hull and decks in 12300kg, for the aft cabin version.
I would expect a slight improvement on the flybridge non aft cabin version.
Hull design, i am struggling to call it semi displacement actually.
Dont the Royal Navy have 40knot displacement boats :) we shall see after the first boat is produced over the next few months how the new hull design is.

Quote
Hi Rob,

For the moment we are looking at a below 20 ton displacement , speed is down to engine size but would be in excess of 25 knots.

I would like to finisgh the entire design and than I can get proper dislacement figures and consequently speed out of it.

The concave shape is part of the design to help reduce drag.

Kind regards,
Hans
 
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