building plate ally boat

hi all i plan to build my own boat about 36' monnohull planing or maybe semmi.

thinking about a cathedral hull just wundering what your thoughts or experiences are on stabillity and performance of this type of hull

 

This link will give you a short and exact apreciation about cathedral hulls.

http://en.wikipedia.org/wiki/Cathedral_hull

It's complicated and time consuming. Very expensive also. Very heavy. Excellent pounders if you want to be shaken. A lot of wetted surface so it requires extra power. Stability is not bad like any almost square (wide boat). A part some river fishing boats the cathedral hulls have fallen out of favor for good reasons.

If you want extra-stability and efficiency you'll get better results with a cata. Well designed cats use about 1/2 to 2/3 of the power of a monohull for the same speed and (moderate) weight.

A simple moderate vee (around 12-15 degrees) hull with sprayers is a good compromise simplicity/results/power requirement. Deep Vee hulls need a lot of power, and may have problems of stability (chine walking).

What the speed you want? you talk about semi displacement...15, 20, 25 knots? what's the use of the boat?

 

yes voyager i think what you say makes sence and that a moderate vee of around 12-15 degrees would suit me better a planing hull would be nice but at the same time comefort is inportant dont want a bone cruncher.

have been in some boats that when you cross a wave they roll and turn suddenly i think this is what your talking about when you say chine walking and i dont like it some boats i have been in dont do this but was to yung to know the difrence in hull design

i have said 36' as i feel that this will put the waight that i feel is needed in an ally to help it punch into a wave instead of bouncing off it (comfort) as i would like it to be universil for family fishing trips or diving trips even comercial if the op arrises .

 

In building alloy boats the big problem seems to be the equippment required and skillset required for good welds takes time , cash , and training.

What is the current opinion on simply riveting the hull?

A good air supply and a $75 rivet gun with $20 rivet trimmer would seem to be all that's needed.

FF

 

re rivet gun

36' thats a lot of drilling and riveting