Boat design consultancy

[MapisM]

Single acting, and has a very neat integrated pump at the bottom.

Yep, it does look like a single acting cylinder, but you can hear the pump running also when lowering the hatch. Shouldn't a single acting work just by opening a valve?
Besides, if it's single, it should be possible to lift the hatch manually, whilst it isn't. Can it have some sort of safety lock (you wouldn't want a hatch to open upon a jump, catching the wind at 50+ kts...), or is the inherent friction sufficient?

 

[MapisM]

Love to see the whole motor....

Sorry AM, I'm afraid I don't have a decent pic of the whole thing.
It's also difficult to take it with the engine in its bay, btw.
There are some nice Utube videos where you can see (and hear!) the beast, if you're interested.
Just a couple of examples:
http://www.youtube.com/watch?v=qsXy8_ChGn8
http://www.youtube.com/watch?v=czrbi-a2hQM
Btw, normally there's a plastic cover over the intake manifolds (which is removed in those clips). With the cover fitted, you really can't see a lot.

 

[MapisM]

Well, the foldable hard top will deal with your cover/protection issues, but where are you going to put your radar dome and GPS mushroom?

I didn't yet think of it in detail, but I reckon that the best possible places are above any of the two goalposts.
The cables should be routed inside the s/s tubes, from which they should exit below the radome and aerials, inside a flexible hose that should go through a (sealed) hole in the HT.
Sure, it'll be necessary to leave some slack in those cables, to allow for the tube rotation, but it should be feasible - albeit not very elegant, maybe.
Do you see major problems with that?

 

[AndieMac]

These are pics of the custom HT fitted to the '97 Princess, by her previous owner, a guy who had imported her new.
AFAIK the HT has been on most of her life in Oz, exhibits no visible signs of flexing or working around fittings.
Pics were taken yesterday afternoon.

 

[jfm]

Thanks, very nice pictures/nice job AndyMac. Do you know exactly how the HTis constructed? It has smooth (gelcoat?) finish inside, so is it 2 separate mouldings bonded together? And the two "ears" that drop down over the side of the radar arch: are they 2 GRP mouldings bonded together with the joint burnished out? (in which case, top marks for effort. The guy who commissioned this must have been a perfectionist!)

I wonder if the diagonal wires either sie of the helm (to stop the lateral wobble that I was talking about earlier) were in the original design or had to be added after sea trials.

Absolutely beautiful job though, huge respect to the team that made that piece of GRP

Interesting also that they decided the radar arch wasn't strong enough to take the weight, hence the 50mm dia s/s strut under the radar

Also, that dinghy storage and crane is a serious bit of kit, sheesh. You have some very skilled boat-modders down there in Launceston

 

[oldsaltoz]

.
Just a few comments:

Making the top from foam core would mean shaping would not be a problem and compound curves are also no problem, in fact they make it stronger.

I suspect none of the above pictures show the leading edge far enough forward to afford any protection from sun or rain, perhaps extending the front a little and giving it a nice flowing curve down would improve the look and rigidity of the structure.

Advantage of foam sandwich is, easy to curve, strong enough to walk on, easy to clean and maintain, can be made thicker and thinner to enhance the lines as well as compound curves. Supports can be any shape from square to round or wing shaped and any amount of taper or bend/curve.

Other advantages include: The ability to build in extra strength with concealed pipe or other section, hidden/flush fastenings, cables for lights, speakers and all manner of electronics.

Just seems a shame to have all that shade and none for the helm and instruments.

Good luck with the project.

Avagoodweekend......

 

[AndieMac]

Thanks, very nice pictures/nice job AndyMac. Do you know exactly how the HTis constructed? It has smooth (gelcoat?) finish inside, so is it 2 separate mouldings bonded together? And the two "ears" that drop down over the side of the radar arch: are they 2 GRP mouldings bonded together with the joint burnished out? (in which case, top marks for effort. The guy who commissioned this must have been a perfectionist!)

I wonder if the diagonal wires either sie of the helm (to stop the lateral wobble that I was talking about earlier) were in the original design or had to be added after sea trials.

Absolutely beautiful job though, huge respect to the team that made that piece of GRP

Interesting also that they decided the radar arch wasn't strong enough to take the weight, hence the 50mm dia s/s strut under the radar

Also, that dinghy storage and crane is a serious bit of kit, sheesh. You have some very skilled boat-modders down there in Launceston

There is no signs of mould joins, and although we have some talented folks here, the work, commissioned by the original owner, was done in Sydney.

There are two 'gullies' (3" deep, square shaped), equal distance apart, running length ways, from aft to fwd, two thirds the length of the top?

Interesting comment about the lateral stays, I had not thought about them until now.

They also mentioned a hull extension (1 metre), which I took to be stern/duckboard?
They removed the old P66 stickers, and put on 70 (suppose 69 would have been awkward ).

The (replacement) crane was put on recently, with a SS base plate approx. 35mm, lots of work involved. The slewing action is too fast, and makes fine (transverse) adjustments difficult.

 

[MapisM]

These are pics of the custom HT fitted to the '97 Princess

Thanks AM, very interesting stuff.
One of the nicest HT jobs I've ever seen on a planing flybridge boat.
Much sleeker than the fully enclosed one on the Fairline that jfm previously posted, for instance.
Though they're probably comparable in terms of technical quality.

Looking at the big inside surface of the HT in those pics, there's one doubt wihch popped to my mind: isn't that prone do condensation on the roof, e.g. at nighttime, with subsequent water dropping on the console, seats, etc.? Not that I can think of a solution, anyway...

Re.the crane, by 35mm s/s plate you meant 3.5mm, I guess?
Anyway, I'm surprised to read that she's too fast.
By the look of it, I'd say it's built in IT by Opac Mare. If so, I know one of their engineers, and can try to contact him if that helps.

 

[AndieMac]

Thanks AM, very interesting stuff.
One of the nicest HT jobs I've ever seen on a planing flybridge boat.
Much sleeker than the fully enclosed one on the Fairline that jfm previously posted, for instance.
Though they're probably comparable in terms of technical quality.

Looking at the big inside surface of the HT in those pics, there's one doubt wihch popped to my mind: isn't that prone do condensation on the roof, e.g. at nighttime, with subsequent water dropping on the console, seats, etc.? Not that I can think of a solution, anyway...

Re.the crane, by 35mm s/s plate you meant 3.5mm, I guess?
Anyway, I'm surprised to read that she's too fast.
By the look of it, I'd say it's built in IT by Opac Mare. If so, I know one of their engineers, and can try to contact him if that helps.

The HT could well be cored with foam/insulator? I have never seen condensation. It really keeps the fly area cool on hot days.

The cranes base plate is 35mm (one and a half inches) thick, the cost, just for the engineers to fit it was $5000.00 (GBP2500.00). The original 'Davco' arrangement was really stuggling with the tender.

The OpacMare is a beautiful piece of kit, but the quick, jerky slew, when retrieving the dinghy single handed, has it swinging around like a cock in a coat-sleeve
I would appreciate any advice on how to temper/slow the movement.

 

[MapisM]

The cranes base plate is 35mm (one and a half inches) thick

I'd rather see the point in a WIDE base plate, but why that much thick?
Re. advice on the crane, if you could post (or PM me) the model details, I can try and talk to that OpacMare engineer.

 

[AndieMac]

I'd rather see the point in a WIDE base plate, but why that much thick?
Re. advice on the crane, if you could post (or PM me) the model details, I can try and talk to that OpacMare engineer.

Modello 3030

The crane is mountedout wide as possible on the port side, which encompasses a small step over a moulded coaming (50mm high). The inboard section 260mm (port to stb.) and 400mm (bow to stern) has the SS base plate, which is 25mm (one inch ) thick (I just went and checked), and fits inside the grp outer shell of the crane. The base plate is welded to an internal length of tube that fits inside the aft fly support pillar, and was added to spread the load.
The hydraulic/electric cables feed under the aft lounge to a custom built alloy covered (powder-coated ) control unit on the stb. side, which is visible from the pic. of the stb side, under the bow of the tender.

I just dug up the instruction manual to get the model number, and surprise, surprise.....on the last page is a trouble shooting section. The second last problem scenario is 'jerky movement'. A choice of fluid level or regulator flow, so will go through the process to fix.

Thanks anyway for the offer.

Cheers

 

[jfm]

They also mentioned a hull extension (1 metre), which I took to be stern/duckboard?

The slewing action is too fast, and makes fine (transverse) adjustments difficult.

The bathing platform looks like an extension. On the original p66 it didn't stick out beyond the hull, I mean it didn't extend beyond the bottom of the sloping aft quarters

The slewing jerkiness must be air in the hydrualics or a problem with the flow regulator to the slewing motor. If it was air you would have sponginess also in the lift mechanism not just the slewing, so I guess it is not air, but it could be a pocket of air somehow trapped in the slewing motor part of the circuit, so worth checking/bleeding. Otherwise check the flow regulator to the slewing motor. These regulators are devices that take the output of a single hydraulic pump (which you have here) and then regulate the oil flow to each separate hydrualic actuator so that the speed of each actuator can be adjusted individually. It might need adjusting, stripping down, or replacing

By the way, it may not be a normal (vane type) rotary slewing motor. It might be a rack and pinion, whereby a double acting ram operates the rack, so rotating the pinion

 

[AndieMac]

Thanks for the info jfm, I was hoping someone might know the extension story, its seems a substantial addition, when she is out of the water.

Also glad the slewing thing is not the normal operation....... ah well, another job on the list....

 

[MapisM]

Thanks anyway for the offer.

U R welcome.
Feel free to pm me if there will be anything you'd like to check with Opacmare.
I only got in contact with them once, but they were very kind and willing to help.

 

[AndieMac]

U R welcome.
Feel free to pm me if there will be anything you'd like to check with Opacmare.
I only got in contact with them once, but they were very kind and willing to help.

As said previously, they are a great piece of machinery and are a popular option on the bigger boats out here.

Dont forget to keep us up with your thoughts on the HT idea.

BTW, I may have missed it, but has anybody asked how you launch the tender on your boat? Is the duckboard hydraulically lowered? Crane?

 

[MapisM]

Dont forget to keep us up with your thoughts on the HT idea.

BTW, I may have missed it, but has anybody asked how you launch the tender on your boat? Is the duckboard hydraulically lowered? Crane?

Yup, I will surely follow up asap.
I was thinking to arrange a trip at the yard to discuss all the details.

Re.the tender, it's a plain vanilla arrangement, with the gangway acting as a crane. A couple of "Y" steel cables attached with snap hooks to the tube visible under the gangway, and to two couples of eyebolts (bow and aft) on the tender.

 

[petem]

If you were just after a bit of occasional shade then one of these would have perhaps fitted the bill...

http://www.power-bim.com/

Pete

 

[jfm]

If you were just after a bit of occasional shade then one of these would have perhaps fitted the bill...

http://www.power-bim.com/

Pete

Thanks for the link Pete, I hadn't seen that page. This is exactly the product I referred to in post #52 above; it's offered as option on Sq78. The video shows the very neat rack and pinion hydraulic motors

 

[MapisM]

If you were just after a bit of occasional shade then one of these would have perhaps fitted the bill...

Thanks also from my part, Pete. I'm not sure to really like that system, though.
And not just because, as previously discussed, there's more behind the HT idea than just a bit of occasional shade (radome & aerials, full FB coverage).
It's rather because, even if that would be the only objective, I'd prefer some simpler manual arches - at least up to the limit where they can be phisically handled. A 78' is maybe borderline in this respect, though still feasible imho, maybe by a couple of persons rather than just one...

 

[MapisM]

Cheers for now, and thanks again!

Yup, I will surely follow up asap.

Hi folks, this is just to keep up with my promise.
Following further checks with my yard, the feasibility of the "foldable" HT was confirmed. But based on their works schedule on one hand, and on my wish to start using the boat by end of Apr/beginning of May otoh, it was impossible to complete the job in time for this season.
So, long story short, the new HT goes into the projects list for 2010 winter, and I won't be able to post some pics of the final result of all your contributions till then - sorry about that.
But in the meantime, if anyone will be around southern Sardinia this summer, be aware that some good bottles of Italian wine will always be available for forumites. And of course, any further ideas which might pop to your minds when looking at the boat in flesh, will be more than welcome!