A Web Site For Do-It-Yourself Small,

Homemade Trimarans


Presented by "Dr. Frank" Smoot, and dedicated

to DIY boat builders everywhere!



7. The "Planing Hull" Experiment...


...a brief visit back to 2011,where I made some very important

discoveries about what works, what doesn't, and why...



As always, it all started out with the best of intentions...


The simple goal was to make a hull that would plane -- hopefully it would be quicker than my previous non-planing hulls...




Gee, it looks like it would be a great hull -- sleek, quiet, and should definitely plane, just like the power boats that inspired it...








Boy, I sure do build a lot of different hulls. But there's just no substitute for real-world testing if you're ever gonna find out what actually works.












A close-up of one of my leeboards -- the one element of this boat that met or exceeded my expectations.


I swear, you just can't beat leeboards for the skinny waters we have around here.




Looks pretty good, even with this smallish 84 sq ft sail.

Note also that I have the planing amas attached in this shot. I'll bet this thing will zip right along!


Sad to say, my first shot at a planing hull was a bust. It was noisy, slow, and created a ton of turbulence.

It plowed through the water, creating a big and noisy bow wave.

I don't know if it ever actually planed, but it was so noisy I wasn't sure I ever wanted to find out.

It was a lot slower than my other boats in light air. But with all this time and effort invested, I thought maybe I could salvage the project with a sleeker, less blunt entry...



What a total pain in the butt it is to recontour a hull. But I still had high hopes...




If anybody know how to make a tortured plywood hull, I sure wish they would tell me...


But in the end, the improvement from recontouring the hull was so small that it just didn't matter.

It was still slow, noisy, splashy, and gave a rough ride. Even with my biggest sail rig (124 sf Laser II), I couldn't get it to perform well.

(Maybe a 10 hp outboard would have solved the problem?)



So it was with no regrets that I cut this hull up in small pieces and deposited them in a local dumpster.

BTW, if you check out the video where I pound on a hull to show the strength of 3mm ply with 6 of F/G on the outside only...this is the hull I was pounding on.

It may have been a failure as a hull, but these things are tough as nails! I literally could not hurt it with a small sledge hammer.




Back To DIY-Tris.com Home Page