Forum thinkning hats on - dingy solution sought

[Whitelighter]

I know you lot are good at this sort of thing so here goes:

So the Walker Bay is probably, in reality a bit to big for the boat. But I like it and really want to keep it because its good for water toys and makes an excellent tender (as has been much discussed). Size wise (L x W) it just about fits, or rather it fits acceptably.

The big issue I have is launch and recovery. At present it is a complete PITA. This is mainly due to the equipment on the boat, my Opacmare Passerelle is a retro fit (Ferretti supplied and electric gangplank and at somepoint this has been upgraded to a hydraulic Pas) but the plated max lift capacity for it is 160kg - the WB without fuel weighs 220kg with the Yam 40 on the back. Ive tried doing a dead lift and the pass complains a lot before sinking. Of course I can lift more with it less extended but then the boat wont clear the swim platform.

The boat also has a crane on the platform (ferretti standard) which has a max lift capacity of 200kg (so closer). however this is 24 years old and needs a full rebuild as its mobile but very stiff and wont lift the weight.

My current non solution solution was to use two 3 pulley blocks to try and lift the dingy manually. I figured that should reduce the force required to lift the dingy down to a managable 35kg. It doesnt, and even tring to use the mooring winch only gets it so far. it a pain to recover and not easily done with three blokes. I think in any kind of swell it would be near impossible for just me and SWMBO

So what solution? I could buy a new passerelle but I a) dont have the budget and b) im not sure the transom would take it. I am assuming a compact 300kg crane like the telescopic Besenzoni one is going to be mega bucks as well.

Would using mor epulleys in a block work? Im suprised 6 isnt sufficient. Can I uprate the hydraulics on the exisitng passerelle with a more powersful/bigger capacity ram (I assume the walkway is just that).

All thoughts welcome

 

[jfm]

I think I'd start with getting a bigger hydraulic cylinder and pump. Quite eBayable. Obviously you have to make sure everything around it is strong enough, but that is where I'd start the analysis. SeaRanger Ancasta is v knowledgeable and sells hydraulic gear as his business. Also check coastal rides - I got an ex Fairline liquidation Besenzoni hydraulic pump and valve pack from them, for peanuts

 

[benjenbav]

Now I grant you that there is an aesthetic issue with this solution but one of these jobbies mounted on the swim platform would certainly take the weight.

http://www.sgs-engineering.com/ec2000-2-ton-folding-engine-crane?gclid=COfw6uqGps4CFcYV0wodAFMLyg

 

[Deleted User YDKXO]

Jez I think there are a number of possible solutions which can be summed up as either increasing the lifting capacity of your existing lifting devices or reducing the weight of the lift

Thinking about the former, as jfm says, you could consider increasing the capacity of the pasarelle lifting ram either by increasing the hydraulic pressure in the system via an upgraded hydraulic pump or increasing the diameter of the ram itself. Probably the latter would be the easiest to do; any hydraulic shop should be able to supply a slightly larger diameter ram of the same length as the original. The downside of course will be that the lifting movement of the pasarelle will be slower. If you fit a higher pressure pump, the problem will be that you're putting 20yr old hydraulic hoses and fittings under greater load and there will be a larger risk of leaks. Having experienced a pasarelle hydraulic fitting let go myself on a previous boat and having to clear up the resulting mess, its not something I would want to risk. Having said this overall I don't like the idea of increasing the lifting capacity of the pasarelle because the structure of the pasarelle was never designed for that increased capacity and of course the transom mounting for the ram will be under greater load

Another thing I was thinking about was whether you could lift the RIB using both the pasarelle and the crane simultaneously ie a tandem lift with the pasarelle lifting one end of the RIB and the crane the other. I dont know whether this works on your boat dimensionally. I guess you would have to rig up a different bridle system and possibly shift the RIB location sideways a bit. It all sounds a bit complicated to me

With regard to reducing the weight of the lift, I assume you only want the 40hp motor for watersports? How about detaching the motor from the RIB and storing it in the 'spoiler' lazarette under the bathing platform? You would lift the RIB into the water with engine detached and then lift the motor out of the spoiler with the pasarelle. Again you'd have to rig a special bridle for lifting the engine and find a way of securing the motor in the spoiler when not in use. What about getting an additional 5hp motor which is permanently fitted to the RIB which is plenty big enough for doing general ship to shore duties and which can be removed and substituted with the 40hp motor when you need it?

I have to say though that probably the simplest solution is to get rid of the 40hp motor, forget about watersports and substitute it with a 15hp motor which is plenty big enough to make the Walker Bay plane with 2-3 people on board. Then no lifting worries at all. My 3.2m RIB with 15hp motor weighs less than 100kg

 

[MapisM]

I have to say though that probably the simplest solution is to get rid of the 40hp motor, forget about watersports and substitute it with a 15hp motor

+1.
Jez, just for the records, if the original passerelle fitted in your boat was the one I have in mind (foldable, rather than extendable), that was only rated for 100Kg.
Therefore, I fear that whoever fitted a 160Kg passerelle didn't even bother to strengthen the transom - and if that is the case, you are already pushing your luck.
I've seen a Ferretti 53 with a cracked transom, even with the original passerelle... :ambivalence:

 

[PowerYachtBlog]

I've seen a Ferretti 53 with a cracked transom, even with the original passerelle... :ambivalence:

Curious about this. I use to lift a 400kg jetski on a Ferretti 53, never a crack. The capacity of the original 53 Passarelle is 350kg.

As for the 150, a friend of myn has a 300 kg rib, he did reinforce and upgraded the passarelle and never missed a beat and no cracks.

 

[Nick_H]

Jez, my 2 cents. You could take almost 50 kgs out of the weight of the RIB and still pull adult skiers by swapping the Yam 40 for a 2 stroke 25/30 hp outboard. Mercury/Mariner used to make a very lightweight 30 hp outboard, but i'd probably opt for the Yam 25, as these had a great reputation, so if you find a used one in good condition you'll be sorted. You could probably lose a few more kgs by swapping the battery for a small high performance jobby (I saved 8 kgs, and moved it to the bow locker for balance), and of course have the fuel tank easily removable so you're not lifting it with the tender. I think that gets you almost to the 160 kgs, plus the RIB will handle better without all that weight on the back.

 

[MapisM]

Curious about this.

Well, not much more I can tell you about that, really.
It was one of the earlier models, as I recall a 1999 Model Year, but moulded in 1998.
And without the optional stern crew cabin, which as I'm told is something that contributes to strengthening the stern overall.
Besides, I can't tell you how deep the cracks were, around the passerelle base.
According to the broker, they were only superficial cracks in the gelcoat (have you ever heard a broker telling that a problem is serious? ), but they seemed rather worrying to me.

All that said, I would rather not use a F53 with a 400Kg ballast so far astern from the COG regardless of whether the passerelle can handle it... But that's me.

 

[MapisM]

Jez, my 2 cents. You could take almost 50 kgs out of the weight of the RIB and still pull adult skiers by swapping the Yam 40 for a 2 stroke 25/30 hp outboard.

Good idea, too. Ref. the battery, he could as well get rid of it altogether.
My old Merc 25hp 2 stroke indeed has an electric start, but it's no big deal to start it also manually.
I guess the Yam ain't different, in this respect.

 

[Deleted User YDKXO]

Curious about this. I use to lift a 400kg jetski on a Ferretti 53, never a crack. The capacity of the original 53 Passarelle is 350kg.

Not sure the capacity was 350kg. The capacity of the original Besenzoni model 169 Jolly pasarelle on my F53 was 300kg. And as Mapism says, flexing of the transom mounting area for the pasarelle on the F53 was an issue especially for boats not fitted with the extra stern crew cabin structure. I considered strengthening the transom on my F53 and I would have done if my RIB weight was anywhere near the capacity of the pasarelle which thankfully it wasn't. Having said that according to my Ferretti dealer flexing of the transom was a known issue on the F53 but not a problem. I'm not sure I believed him

 

[vas]

Can we have a couple of pics of the original passarelle and the one fitted now plz?
Mike and others when you talk about transom flexing you do mean on the ram mounting point and not on the actual passerelle mount right?
If so, and assuming it's easy to upgrade the ram. I think that reinforcing the ram mount area is no big deal especially when ram is out for replacement...
I ve fitted a heavy 250kg rated 2.7m long passerelle on MiToS without existing mounting points, and there V minimal flexing even with two or three 60kg teens jumping about fully extended

OTOH, my mate has one of these folding bezensoni with a really tiny main ram that even smoothly stepping from the dock moves down 10-15cm but will happily lift a heavily laid up 3,2m rib with a 9.9 two stroke

V.

 

[KINGFISHER 9]

https://hurleymarine.com/shop/dinghy-davit-boat/h3o/ ... or others in the range.

 

[Whitelighter]

Thanks all. Good suggestion about a lighter 2 stroke. I take it these are no longer made new.
I assume also the Yam 40 is probably worth something in equivalence value wise.

Ref: the old/new passerelle: I don't have any pictures of the original. The current one has the foot of the ram on the swim platform, that her than on the transom. I am concerned about flex in the transom - my boat does have the crew cabin fitted so I'm not sure if strengthening the transom is an option. Ill try to find a picture of the current set up.

The final option is to get rid of the whole rig and get a lighter tender - I do want something that will tow a skier though. Would a Ali rib eye with a jockey and say 20hp toe a skier?

 

[Whitelighter]

https://hurleymarine.com/shop/dinghy-davit-boat/h3o/ ... or others in the range.

Certainly an option, thanks

 

[Whitelighter]

Nick, what battery did you get and where did you buy from?

 

[benjenbav]

Incidentally, Jez, my suggestion of a frame for an engine crane wasn't intended to be facetious. Obviously the garagist's frame on wheels isn't going to work literally, but if you had some mounting points on the corners (-ish) of the platform you could assemble a frame with a hydraulic lift (or blocks if you prefer) which could be put in place for launch and recovery and dismantled and stowed the rest of the time. You would need to do the calcs but assuming the platform takes the weight of the tender (+ operator) then the same weight spread across the platform ought not to be a problem.

Mounting points might be no more unaesthetic than chocks. The frame shouldn't need more than widely available welding skills.

 

[Freebee]

having assembled and dissasembled a garage engine crane quite a few times, this is not something you would want to do on a regular basis, the componenst are heavy, mild steel and the components would rust, in any case the highest rated capacity is with the shortest jib length, which may not be long enough to reach the dinghy.

 

[longjohnsilver]

Just a thought, but is there any chance of using rollers such as you find on a rollercoaster trailer and then winching the tender onto the bathing platform? I've no idea of the height of your platform from the sea, but if relatively low this could work with a swinging arm and maybe an electric winch.
Obviously won't work when moored up in a marina but don't suppose that will bother you too much.

 

[jfm]

It's no problem reinforcing the transom and the point where the hydraulic cylinder mounts. Just normal GRP/epoxy work - easy

Nick, do you have a link to your small high performance battery?

 

[Whitelighter]

The hydraulic cylinder doesnt mount to the transom, it's foot is flat on the back of the bathing platform. I think what is happening is as it pushes the weight up the hinge point (the mount for the walkway) is pushing down on the transom causing it to bow. There is also stress cracking where the passerelle is mounted, but it's superficial. The pass has been on a while - at least since the previous owner looking at the pumps etc.

Having looked at the way the H3O launches its not ideal and I'd rather find another solution.

I think the solutions are:

1) beef up the passerelle hydraulics/transom
2) get the standard crane off, reconditioned and lighten the boat (fuel out, new battery) to get it to the 200kg crane limit
3) sell tender and buy a lighter rig. I still want one that will tow a skier so this may not actually solve the problem, plus I really like the WB so am keen to make it work.