Quote:
Originally Posted by Bushwacker
On the gunnel supports, are you building a cap from scratch or re-using the old cap? Frizz is right, hard spots at the gussets could be an issue. An alternate approach would be to use a thick core in the cap and make it look like an inverted U, overlapping the hull on the outside and extending down several inches on the inside. The vertical legs of the U create a lot of stiffness and extended all the way down to the deck on the early Moesly CC's. You could get similar stiffness with a shorter and thicker leg, maybe with a rib along the bottom of it. The best way to attach cap to hull would be glass tabbing with epoxy on inside and outside; next best would be to use pop rivets or machine screws; weakest joint would be to use tapping/sheet metal screws with sharp threads that cut the glass fibers and tend to come loose.
If the entire inner liner has been removed, I'd recommend adding balsa core to inside of hull ala billythekid's thread:
http://www.classicseacraft.com/commu...ad.php?t=24262
A tall thin beam/stringer is very stiff in vertical bending but it'll tend to buckle if it's not supported from the side by bulkheads. The original boats didn't need many bulkheads because the cockpit sole was well bonded to tops of the stringers over their entire length, providing significant transverse stiffness. This bond is important, so I'd use epoxy thickened with glass fibers to bond the deck to the top of the stringers, even if poly or vinylester is used everywhere else.
Regarding stringer attachment, I doubt any reinforcement is needed there because the 4-stringer hulls were really well made, with the glass stringers being installed about halfway through the layup. The stringer tabbing is extensive and thoroughly explained in great detail in the Boating Magazine article on the 1969 Seafari 20 in the Literature section. (To get to it click on Classic SeaCraft Home in the blue bar at bottom of page, then click on Literature tab.) I think that is a .jpg file however, so not very readable but I can send you a very clear .pdf version if you PM me with an email address.
If you're planning to install a bracket, I'd suggest you read my Pros & Cons thread at top of this section. Sounds like you're already moving the gas tank forward, but you might also consider moving the console forward some as well. Although the stock 20' hull is extremely stiff, it's relatively light with less beam than modern 20's. This makes for a great ride but it's more sensitive to weight and weight distribution than a heavier fatter hull, so it's good that you're asking questions and paying attention to this stuff before you get too deep into it! Welcome aboard and keep us posted on your restoration! Remember that good pictures are worth a lot of words, plus the guys on this site love boat porn anyway! |
I am reusing the old cap. when i bought the boat, the cap was already cut into a "3 piece" style. i have restored the cap edge and planned to attach it back to the hull with either rivets or through bolts, no screws. i have boxed in a 16" wide transom area, tabbed to the hull and stringers which acts as hull side aupport as well. the back of the cap will be glassed to the top of this transom box
i had originally planned to bond the deck to the stringers using 5200, not recommended? obviously the sides of the deck will be filled with cabosil and tabbed to the hull sides.
the deck will be marine ply. I was going to use poly resin to glass the bottom, any issues with the thickened epoxy bonding to the poly? would vinylester bond better?
I am planning to do a bracket. ive studied your thread quite extensively. infact i have been stalking this forum for quite some time reading every build thread i can find studying before signing up. the plan is a bracket and an etec 90 or suzuki 90, maybe 115's depending on what i find when the time comes. i'm trying to keep this boat as light and fuel efficient as possible since my grady white is such a gas hog.