MiToS re-built/fit- versilcraft Mystery43

[P4Paul]

blimey!

just came back after a full day of meetings to my office, slightly dizzy and on a very dim 19inch monitor, saw the pic and thought it was snow/ice on the boat (wondering what's the point of posting it here tbh...). Only after reading the text did I realise what I was (almost) seeing...

Fking unbelievable, what a pity, curious how it's going to look like after a couple of winters and sun. And I wouldn't like to be walking on in barefoot midday either.

It's not a case of enthusiasm, it's also a case of having an overall perspective and I'm afraid taste!
Need a rest.

cheers

V.

Now I have to admit that if it had been nicely finished I would have loved a large photo to hang on the wall at work.


Just to remind everyone of the fact that a shite idea, however well executed, will always be a shite idea....

 

[petem]

Looking very very nice Vas. I love the black headlining over the helm. Much respect to you

Purely as light relief (rather than big thread drift) here is a pic I thought you would enjoy, having done some mosaic tiling. This is a boat moored in Antibes. The guy just didn't think it through before starting to stick the tiles - indeed he didn't think it through on any level really. I wanted to shout "kingplank" to him as he worked his way across the foredeck. The black mat right at the bow hides a very dodgy "interface"! Anyway, he has the same enthusiasm for boat refitting as you at least so for that must be applauded

I've a feeling he might have started on the starboard side! He probably thought it going well at first!

 

[vas]

I've a feeling he might have started on the starboard side! He probably thought it going well at first!

clearly...

tbh it's not surprising as the guy obviously spent more time shifting the boxes of tiles from his car to the boat than thinking the way he'd lay them

Mind, for most of the "easy" and "straightforward" jobs done on MiToS I've spend more time sketching, designing and thinking out the design and installation implications that actually doing the job. OK there are some notable exceptions but you cannot simply start working on it without sorting out all the issues first.
I'm afraid if the same guy would have decided to lay teak veneer on his deck the end result would be of similar quality

cheers

V.

PS. @KevB NO

 

[vas]

good afternoon all,

managed my 1h or work for this week
namely measured and corrected the passerelle ram placement on the transom. I want to make sure I get maximum travel without squashing the bathing platform on the down travel and without ripping the passerelle main pivot on the way up. Happy to report that the design allows for 90degrees travel and with the transom slope (measured at 22deg) I get 61deg above horizontal and 31deg below horizontal. Tomorrow I'll establish if I can use the passarelle to "walk" down to the water
2.7m long and 22deg slope down means 1.5m from the passerelle mount. If it doesn't dip in the water it will be something like 10cm above...
61 deg up means that it's 7deg off the transom slope which is imho good enough and quite safe for kids fooling around there. Two sketches follow, any objections or extra points to consider got to be in today as it's day off tomorrow, weather is good so I'll spend the whole day in the boatyard (for a change, must be the first time since mid September!)
The two blue circles show the travel of the ram, the yellow is the ram pivot on the passerelle. So 600mm short or 1030mm long is what gives the possible positions.

got some thoughts on the bathing platform but not enough time to sketch them as yet.

cheers

V.

 

[jfm]

Looks good Vas. The 7 deg off the transom angle at the top looks ok in that it gives good children playing headroom. Have you compared the passerelle angle to the ram angle at that full extension, to see if the passerelle and the ram don't clash (which would bend the ram of course)? Sorry if TYHTSE

 

[vas]

Looks good Vas. The 7 deg off the transom angle at the top looks ok in that it gives good children playing headroom. Have you compared the passerelle angle to the ram angle at that full extension, to see if the passerelle and the ram don't clash (which would bend the ram of course)? Sorry if TYHTSE

yes, done that J, it's fine.
Problem is that the top hole of the ram transom plate goes straight on the 25X60 aftdeck frame :argh:
and it's not a port/stbrd beam I'm talking about, its a bloody bow/aft oriented beam. Will need to do a box section out of iroko, cut with a fein like tool the bit of beam fouling the hole, dremmel the ss screws securing the plydeck onto the beam and sort it all out. Not a big job but doesn't fit well with my current timetable. We shall see.

Needless to say I cannot shift the plate up as I'll get a bent ram nor down as the ram on the low spot will crush the swimplatform. Nice...
On the plus side this area is plenty strong with all the reinforcement plus the aft deck, so shouldn't have any flexing and cracking there

cheers

V.

 

[BartW]

Problem is that the top hole of the ram transom plate goes straight on the 25X60 aftdeck frame :argh:
and it's not a port/stbrd beam I'm talking about, its a bloody bow/aft oriented beam. Will need to do a box section out of iroko, cut with a fein like tool the bit of beam fouling the hole, dremmel the ss screws securing the plydeck onto the beam and sort it all out. Not a big job but doesn't fit well with my current timetable. We shall see.

isn't it more easy to make a new ram transom plate, different size and different screw positions or fix the existing one on a new SS support ?
excuses if I missed some other details on that Vas.

 

[vas]

isn't it more easy to make a new ram transom plate, different size and different screw positions or fix the existing one on a new SS support ?
excuses if I missed some other details on that Vas.

no, you are right Bart, I could do it, just I'll have to fabricate a rather large piece to be able to place screws where I like
it wont necessarily be smart, could be fugly.

OTOH, I do have a slight issue with the existing plate being flat whereas my transom isn't. Forgot to check the roundness at 150mm wide horizontal, will do and may end up having to modify the plate anyway.

hm, I could also turn the plate 180deg and get the holes to match (ok, just thought of that...)
The only downside will be that the slopes of the support plates will be wrong forcewise, as in it will feel wrong, but will be perfectly adequate for the job. Will think about it.

cheers

V.

 

[jfm]

its a bloody bow/aft oriented beam. Will need to do a box section out of iroko, cut with a fein like tool the bit of beam fouling the hole, dremmel the ss screws securing the plydeck onto the beam and sort it all out. Not a big job but doesn't fit well with my current timetable.

Erk! I see the problem. Not an impossible job but I can see that this could involve plenty of faffing about and waste a day

It is hard to make any suggestions without seeing the job and knowing all the dims, but I wonder could you drill a 25mm hole athwartships in the fore-aft beam, to create a cavity into which you can place an M12 (say) nut and fat thick washers for an M12x 150 (say) bolt thru the transom to hold the ram mount. A 400 x 60 (or whatever) pad of ply glued under the wooden beam would make up for the strength loss cased by the 25mm hole.

 

[KevB]

If I've got the problem straight in my head and what you need to achieve, what about a more manly version of these?

Possibly make your own barrel that stretches from one fixing in the back plate through to the other. So if there is 4 holes in the back plate for fixing, make two barrels with two holes each? Epoxy them into the beam to keep the strength.

 

[MapisM]

It is hard to make any suggestions without seeing the job and knowing all the dims, but I wonder could you drill a 25mm hole athwartships in the fore-aft beam, to create a cavity into which you can place an M12 (say) nut and fat thick washers for an M12x 150 (say) bolt thru the transom to hold the ram mount. A 400 x 60 (or whatever) pad of ply glued under the wooden beam would make up for the strength loss cased by the 25mm hole.

Yup, been there, done that.
Actually, in my boat there wasn't any choice, cause the whole stern is practically built of 20cm thick solid wood, but the good news was that no strenghtening plates were necessary, in spite of the rather substantial leverage: 250cm length/250kgs load at max extension. A dozen of years after, the thing is still working flawlessly, with zero flex/torsion.
Vas, if you would like to have a look at some more pics, just ask.

Oh, and for the records, this was the original construction:

 

[jfm]

Yup, been there, done that.[/IMG]

I think you're tuned into a different radio station MapisM . Yours is just a straightforward bolt through job with penny washers. You don't have the fore-aft beam problem that is at the centre of Vas's question. KevB's picture in #1050 illustrates the concept of what I proposed in my post #1049 to deal with the longitudinal beam

Is yours a Besenzoni? I'd recognise that welding anywhere - I have plenty of it myself in places (like yours) where Besenzoni decided no-one will see it!

Yours has a black wheel/castor at the dock end. I expect it is intended to be placed on the dock for loading heavy things onto the boat and I expect the hydraulics have a relief valve to avoid damage if the boat goes down on a wave/swell when you are doing this. It's a nice Besenzoni feature that I use now and again when loading the boat up (I don't have the wheel so I use a bit of scrap carpet)

EDIT - I like very much the feature on yours where the mount wraps over onto the iroko gunwhale top and takes plenty of its strength from there, and uses that beam to spread the load right across the transom. Good going also to line up the deck caulking with the joints in the vertical strips on the transom, despite the hurdle of a curved transom and therefore varying triangulation/parallax!

 

[vas]

nice setup MM, but you're in a different league.

And that's not only because as spotted by JFM you haven't got a floor frame to tackle, but you also have a SINGLE plate that holds the pivot for the passerelle AND the ram. Lucky you Mind, stresses in your case are larger as the angle between passarelle and ram is v.narrow, but having a single L-shaped support element makes life so much easier.

In my case the passerelle pivot is 610mm from the ram transom pivot (yours are more like 250 and if so).

KevB, yes could do such a trick, but I'm not happy doing it as I feel it compromises strength. Further, it wasn't made clear that only one out of 4 holes has this problem and applying Murphy's law it's the upper one getting the highest forces

Next time I'm down, I'll check if turning the plate 180deg will make it work. That way means that the top bolt goes OVER the deck, the lower UNDER the deck and the two side ones on the beam across. Not bad

I'm also pretty sure I'll have to get the plate to the machine shop and have them bent it a bit to fit the curve. Not happy filling gaps with either timber or worse caulking.

two pics showing the plate and the through rod and allen head bolts in before and after state:

Rest of the week looks lost as well as the w/e as I'm away. Hope I'll get something done next week...

cheers

V.

 

[BartW]

Vas,

perhaps you can add 2 holes / screws, left and right of the middle top hole, exactly left and right of that beam ?
(and do the same on the bottom edge, for geometry / esthetics)

 

[jfm]

Vas,

perhaps you can add 2 holes / screws, left and right of the middle top hole, exactly left and right of that beam ?
(and do the same on the bottom edge, for geometry / esthetics)

Yup having now seen the picture I agree. Unless there is lots of €€€ budget to have a new bracket made, I'd just drill 2 holes at the top, left and right of the "problem" hole, and insert a dummy bolt in the "problem" hole. Then it can be installed the right way up. While it is in the drill press having 2 new holes made you might as well countersink them all so you can fit socket head CSK bolts as in MapisM's picture

 

[vas]

Bart and John,

not so keen with the twin holes idea as the main transom frame beams are around 40X60 supported by smaller (approx. 30X30) ones either side. The twin idea means I'll drill through them and I don't like it. I'm sure nothing will fail, but I'm not happy.
Tried sketching a bit, maybe a round 200mm plate would sort out all my probs as the top to bottom holes can be spaced to wrap around the deck beam.
Since I've got a few more things needing lasercutting out of SS, I might as well do them all now...
Haven't manage to find any decent pics of the lazarette area here's one that gives the general idea of the transom construction. Keep in mind that all hull is 15mm thick plywood, transom is 18mm and the painted sides of the hull (above the top chine) are 12mm.

cheers

V.

 

[jfm]

I think I'd be happy to drill through the 40x60 or 30x30, with a plate ( like 40x100x15 Ali) on the inside serving as a big washer, and sika292 or 3M 5200 gluing the "washer" to the wood

 

[MapisM]

Doh! I had to re-read the previous posts, because I understood that your concern was about the need to go through thick transom frames, which is rather an advantage than a problem, in terms of structural strength.
In fact, I didn't really understand the need for the complications suggested by jfm and KevB...
In hindsight, I obviously missed this statement of yours:

Problem is that the top hole of the ram transom plate goes straight on the 25X60 aftdeck frame :argh:
and it's not a port/stbrd beam I'm talking about, its a bloody bow/aft oriented beam.

Oh, well. Now I see what you mean, of course.
Anyway (in reply also to jfm), the above passerelle was made by Bitecnomare, a company radically different (much smaller and less well known) than Besenzoni, but which developed some clever ideas, like the single steel plate supporting both the passerelle and the ram. They even managed to get that patented, which I guess is one reason why that solution was not used by other builders (though the patent might be expired by now, I'm not sure).
The only drawback is that each and every steel support has to be custom built for the transom where the passerelle is to be installed.
You can't appreciate that in the pics, but aside from following exactly the transom angle, the steel plate is slightly bent to follow its curvature, also at the top, where it goes round the iroko gunwhale plank.

I'm mentioning this because maybe you might consider having a similar steel plate built also for your passerelle, which not only could eliminate the problem with the much lower ram plate, but would also make the installation easier overall.
Btw, now that I've seen also your last pic with the transom structure, TBH I think that also your transom would appreciate the inherent higher strength+stiffness of the single plate mount...
Actually, while I'm pretty sure that the folks at Bitecnomare could do a good job (since they do it for any installation on a new boat), I'm not positive that they are willing to build just a plate alone.
I can give them a call and check that out if you wish, but as you can imagine, for them is just a selling point for their own passerelle...
...Otoh, if you know someone good at working with s/steel, maybe you could have it done by them.
No problem to send you more pics with the details of my installation of course, if you think you could use it as food for thought.

 

[jfm]

Problem for Vas would be that the plate would be 700 x (about) 300 and if made in beautiful 5 mm plate like yours MapisM it would weigh a heck of a lot. Plus you'd need industrial grade rollers to put a curve around the 700 axis so immediately this becomes a high end €1500 project and 80kg extra . Just saying - I do like the idea of what you suggesting from engineering pov

I gotta say, you seem to be able to patent anything in Italy

 

[MapisM]

Well, I guess they patented the specific industrial application, rather than the bent steel plate per se...
...not that it matters a lot, these days: if it weren't that the market for this stuff is just a small, unattractive niche, we could buy a dozen of these things on Alibaba for the price I paid for one - regardless of any patent!

Fully agreed re. not being a trivial DIY job, anyway.
But Vas is full of resources when it comes to customized jobs, you never know!