ply bulkheads

Hi I’m currently designing a 33’ catamaran and have not been able to find information on bulkhead widths so my question to you is this.

What width should my bulkheads be I have the option of 6mm 9mm 12mm or 18mm any information would be of great help

 

I AM A BIT WOORIED,
sorry, caps locks whas not intended though
If you don't know what stiffness you need in your bulkheads, and how many you need, think about all the other things you dont know!
I would say 12mm, will you then use that and go to sea?

 

Should have explained

Oh, sorry it does sound a bit “out there” but no Im actually looking at a set of plans, very very old plans, and from researched information there are a lot of new techniques and materials for bonding and strengthening so Im trying to find the best way to approach and alter the designs at hand.

thankyou for your reply

 

I think 12mm would be "normal" for a monohull sailboat of that size, but catamarans are stressed or loaded differently, you have enormous forces from the crossbeams, I guess..

 

katfish

I am building a 42 ft Wharram with West System epoxy, and the bulkheads are 18mm ply. I would think that for a 33 footer, 12mm would be fine. It also depends on how many there are. The Wharram has them about every 5-6 ft.

 

im building a 17' shanty boat (wich i intend to call the sea serpent'and intend to have a bulk head every 3 feet,would this be ok?

 

It's impossible to answer simple,
it depends on the skin thickness and longitudinal stiffeners.
With some stringers say 20x20 to 30x30mm and 6 to 9mm skin it sounds reasonable. BUT, it depends on deplacement, speed, conditions etc.