Cat bulkhead design

Trying to figured out bulkheads for the bolt connection between crossbeams and floats .
Floats are rather light foam/CFC .
Bolts are M14-M20 .
Question is how to spread bolt compression load into relatively light foam hull .
Regards

 

What are the forces at each bolt and what is the laminate schedule for the bulkhead?

 

I am looking for an idea for a bulkhead or bulkhead box that will transfer forces float/crossbeam.
Crossbeam connection are bolts appproximately quadrant 0.5m pattern , four vertical bolts will connect the deck to the crossbeam.
Question is relatively easy and cheap way to transfer bolt forces to the foam hull .
Purpose is road transport.

 

Try to post your images/sketches on this website, not another with endless pop-ups and highly suspicious links.

But in essence, more information is needed, as Gonzo notes.

 

Floats will be 120cm high and 75-80 cm wide . Bolt spacing is approximately 0.5m transversally .
Estimated LOA will be 9m .Estimated BOA 4-5m .
Light "engines" will be twin Mercury 60hp .

 

The transverse torsional moment of the 0.5m section is my concern . One of many ...

 

Yes, there are many. Many many. Is this a sailboat? How many naked beams are there? What sea state will you be operating at?

 

Two beams. Currently it is supposed to be a motor yacht.
Mediterranean summer conditions.

 

I removed my post because I did not realize this is a powercat until I reread.

The connections in my Skoota powercat which is foam core are a glass socket and metal strapping holding an S830 beam. It is quite complex. But the beam lays in a socket, not just a simple connecting point.

I’d say you are in water a bit over your head; to be polite here. You can’t just bolt this thing together eh..

 

The socket is tempting, but I'll be relying on four screws spaced 0.5m apart. I don't know what diameter I can reasonably enlarge these screws to. Maybe 30mm.

 

There is a significant amount of unknowns.
Firstly, what displacement is the boat, how far apart are the beams, what is their span between hulls, what speed is the vessel going etc etc.

 

Seems it will not work. What is the beam made of? Solid wood, built up, composite box? There is a lot of concentrated stress in what you propose.

The norm is to clamp the beam around with a metal plate/Ubolt and polyurethane sheet as density tie sheet.

 

Displacement is limited by car load capacity . 1000-1200kg.
Beams will be about 5m apart .
Span , the range results from the data above is 2.5-3.5m.
Speed at calm sea , 2xMerc 60 hp , depend on prop and lower units .

 

Beam is kind of mystery .
"density tie " meaning please ?