clear materials

I'm curious what material would be best for my idea. I'd like to build a sailboat with a "glass" bottom. I'm assuming that a design like the pioneer 590 would be okay built with plexiglass panels that would replace the plywood. Is this a probable cause to begin summing up the costs of the wood? Would she be a good candidate for plexiglass construction? Would acrylic be a better choice? I'm looking for a semi planing hull. This looks like it would be, but I don't know for sure. http://www.boatdesign.net/nyd/P590/

 

Check this out, a full planing hull? http://www.dngoodchild.com/5300.htm

 

Plexiglass is brittle and difficult to work with. Glass bottom boats usually have small viewing windows because the clear window is thick, heavy, expensive, and needs to be protected (from trailering or beaching for example.)

 

Ok. Would bullet proof glass work? Like the stuff in banks. No trailering...

 

I also want to scale her double. Would double the thicknesses of everything in the structure.

 

Actually fourth four feet sounds perfect.

 

Welcome to the forum.

No, you can't scale it up double. Simple physics, that most folks have difficultly grasping, but just trust me, no, you can't scale it up 200%.

Clear plastic panels, to replace the structural panels, isn't practical and will jack the build cost exponentially. Polycarbonate is the material you'll likely use, but making Lexan hull panels will make buying plywood, look like a trip the second mortgage store. One 3/8" thick 4x8' sheet of Lexan is about $400 (USD), while the best 3/8" (4x8 sheet) BS-1088 grade marine plywood is about $100. A good quality exterior, construction grade plywood is in the $30 range, so pick you poison.

From an engineering point of view (no pun intended), a clear panel bottom is possible, though you'll need to keep the boat fairly small to keep it practical. This isn't something the average back yard builder could do, unless you have an oven big enough to cook big plastic pieces at 300 degrees. Edge bonding and dissimilar materials bonding will prove problematic, but could be solved. The obvious next question is, what kind of budget do you have, as this isn't going to be particularly cheap. Next, do you know how to weld plastics (really well)?

 

Ok so maybe this one I a big budget item.

 

Although it is an old thread I think it is worth clarifying a couple of points. The transparent bottom can be done and has already been done several times. It is necessary to take certain measures to reinforce the bottom around the "window", both internally and externally, the area where the plastic is placed must be perfectly flat as well as the plastic it self. You could place several "windows" but not larger each one than 1000 x 500. Polycarbonate is the ideal material, although not the only one, and usually 2 or more layers are glued.
A semi-planing hull is not suitable for these inventions due to the relatively high speed.