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Re: Ok - lets save 10 lbs
By:Mark Bodnar
Date: 8/15/1998, 12:14 pm

I check your site - the plywood weight estimator was relatively close - it had my current boat at 43 lbs and I weighed it at 44-45.

Saved weight - No rub rails, no deck fiberglass, only glass inside cockpit, no tape on outer seams.

Are their 10 more lbs to save? You talk about using 1.5 or 2mm ply layered with glass, is that stronger and lighter (certainly not as easy if you must multi layer glass or glass inside and out) as 4mm (epoxy deck, glass outer hull).

My footbraces are supported by 2"diameter x3/4" blocks of pine (little thick but it lets me epoxy a wing nut into the block and avoid hole through my hull)-still quite light

What exactly is gained with kevlar? For another discussion on the list it is torsion resistant, not puncture resistant - I would imagine that the whole structure of the boat provides adequate torsion resistance while my prime concern is punctures or compression.

Clearly weight can be saved by shaving a little off every component but are there any more significant factors you can suggest?


> The easiest way to save weight is to know where the weight is.
> No offense, I am sure that like most other builders you have little
> or no idea where the weight is. My web site


> has a plywood boat weight estimator. That might be suitable for
> an initial pass.

> Careful choice of materials and using the right amount of material
> halps. Here are a few hints (My CLC 16' boat weighed 31 pounds and
> its construction is noted someplace on my site). Using 1/4" x
> 3/4" redwood rub rails saves a couple pounds. Using a lower coaming
> ring (1/2" rise is enough for most spray skirts.) and 1/8"
> lip with 4-6oz glass on the top saves a pound. (If I built plywood
> boats any more I would try using 1.5-2mm okoumee plywood with glass
> on the exterior.) I don't know your wife but I usually built my hulls
> from 3mm plywood not 4mm. Don't fill the weave in the (1" over
> 2" )seam tape and use a small radius, 1-2" saves 1/2 pound.
> If you use the 2 3mm x 3"x13" plywood blocks as supports
> for foot braces - try 1 3mm x 1" x 13" block (use 10-32
> x 3/8" screws counter sunk) saves 1 pound.

> Kevlar and good glass is available by 2 day air from several
> suppliers, Fiberlay and Raka (glass) and FibreGlast (kevlar seconds),
> at reasonable prices.

Messages In This Thread

Re: Ok - lets save 10 lbs
Mark Bodnar -- 8/15/1998, 12:14 pm