First weigh-in

Well, after filling the weave on the hull glass, I decided to throw the C16 on a scale and see where I stood for weight.  Looks like around 30lbs at this point.  I'm hoping that the end pours, deck, and remaining glass don't add more then around 15 lbs, as I'd like to keep this thing under 50lbs fully rigged.  

Did anyone on here weigh their boats throughout the process to see how close they were coming to the target weight?


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RE: First weigh-in

Hello Chris,

I'm building the 17LT.  The hull, just before external glass tipped the scales at ~ 28 lbs.  After glass and the firsrt filling of the weave was ~ 31 lbs., after a total of fours coats of epoxy, was a smidge shy of 32 lbs.

So have you completed your 16, and if so, what was the final outcome?

Thanks,  Art

RE: First weigh-in

keeping it light, while not making compromizes with strength is one of the big advantages of building your own boat.   i paddle with a number of meet-up groups in the maryland area, and in addition to the beautiful looks of a home-built, i would say the second-most commented feature is how light the boat is compared to comparable glass and plastic craft.

i have a chesapeake west river 180 (18 feet) fully rigged including perimeter lines, hatches, deck rigging, additional paddle hold downs, heavy aftermarket seat, and under deck waterbottle holder that comes in at 49 lbs total and it has a fully glassed deck and interior (both hull and under deck is glassed on this design) and generous rubstrips for beach landings.  so on the chesapeake 16s, low 40 is a very reasonable target.  

that said, its very easy to get 'fat'. and to acheive a low 40's have to pay attention to all elements of construction.  below is my standard punch list of how to keep it light without any significant give up in strength (e.g., like swapping out 4 mm okoume for 3mm).

1 pick-up/sand off every bit of dropped epoxy.  if its not in the weave or part of the fill coat or between a joint, or in a properly sized fillet, it's just extra weight with no benefit.

2 mask your fillets to keep them the width you want and where you want them.  when a fillet has hardened a bit, pull the mask will get perfect fillets, strong, minimum weight.

3 pay attention to your joints, keep them tight (there has been a lot of discussion on beveling recently.) perspective is bevel for a tight joint.  substituting epoxy as coring material, that should be okoume, costs weight and is not a trade that adds strength.   there are places where one has to deal with impacts resistance and techniques to deal with that (e.g., rubstrips)...but they should not be applied to standard joints or the entire structure.

4 the sheet clamp and the deck arch can be rounded over signficantly on the inside-most corner (the corner most close to the center line of the boat).  the purpose of the sheer clamp is to make for an easy-to-glue interface for the deck to the hull and in the chesapeake, provide material for the deck rigging screws to bite into  you could easily lose 1/3 to 1/2 of the material (imagine its cross section being more of a triangle than a rectangle) and preserve all of the benefits of a sheer clamp with none of the extra weight.  the inside of the arch can be rounded over signficantly as well.  this also has the added advantage avoiding sharp edges which can snag equipment or ding your knee)

5 do a good job of planing the sheer clamps (check the fit to the deck) to avoid large gaps that will fill with epoxy (this relates to 7 below)

6  pre-pour your end poors.  build a dam and make a very thick epoxy/wood-flour mix and keep them jno bigger than you need them and you can save a more than a couple ounces.  first, pouring an end pour requires the pour to be pourable....e.g., unthickened and heavy.  less control means you inevtiably pour more than you need to be safe.  i sort out where i want the grab loop hold to be and make a dam extending only one inch beyond that.  i use peanut-butter thickened wood flour to fill the space.

7 plan your deck attachment session....practice....have help...keep the temperature down to buy yourself work-time.  for the chesapeakes, getting the deck on is one of the most squirely elements of the build.   there is a price for that arched deck (compared to a shearwater or other design where the deck is pre-shaped) and that is you are dealing with a handling something that does not want to be in the shape you want it.   in addition to all the normal hazards of working on a target that does not want to stay put, one of the invevitable results is expoxy getting where you don't want it or need it.  in particular i am talking about excessive squeeze out and epoxy on the deck and inside of the boat as a result of the putting-the-deck-on process.  if you do a good job of planing the sheer clamp and test fitting (see 5 above) you will need less epoxy to glue it and you will have less need for epoxy that can get in the wrong place.  i pre-coat the top of the sheer clamp with unthickened epoxy.  when i go to actually attach the deck, i only put a a thin coat of cabosil thickened epoxy on the outermost 7/8 of the clamp to avoid squeezing an excessive amount of epoxy into the the boat where i can't wipe away the excess.  having a plan to keep the deck centered (vs letting it move from side to side while trying to install it) so the deck only comes down on the sheer clamp also keep the glue where you need it.  finally, on the inside of the cockpit (which is accessable becuase the cockpit is already open) you can mask off the sheer and deck with packing tape and remove it before the epoxy remove any excess squeeze out)

8 don't nail the deck to the hull....use duct tape.  takes out about a pound of nails, avoids the challenge of driving all the nails straight without one of them going side-ways , much easier to sand/get a smooth deck without having to work around the nails heads.  this works well with an approach where you use straps or rope to pre-bend the deck (then apply epoxy to the sheer) and then use duct tape for the final pull-down of the deck.

9 glass the deck before doing the coaming.  much easier to work on.  avoids the problems of how to sand it smooth under the coaming.

10 built the coaming a piece at a time or use the deck as a mold.  clean it up and round it over signficantly.   this makes it lighter and more controlled.  when attaching to the deck, look for and immediatly clean up any squeeze out.

11  generously round over your chine and in particular your deck/hull joint.  this takes some weight off and has the added benefit of softening up the corners which makes the chine significantly more resistant to impacts (like paddle strikes or bumping into the side of your garage).  this technique should be coordinated with how you will paint/decorate.  on the chesapeake, if you are going for a bright hull, this approach exposes the layers of the okoume...which some people find does not look very nice).  but if you are painting the hull....go for it.

am sure other have their best tips for keeping it light as well.

good luck


RE: First weigh-in

+1 to all that Howard says except for 6. Just  skip the end pour and replace it with a piece of shaped light wood.



RE: First weigh-in

Thanks for all the building tips.  For this first biuld, I'm following, or will follow tips, 1, 2, 5, 6, 9, 10, and 11.  I've found that learning how to build light is more than a one boat process.

Regarding 6, I glassed the keel seam well into the ends, so made the end pours about half what is called for on the plans.


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