23 Sceptre - last unmolested one

[77SceptreOB]

Nice Drawing!

[FLexpat]

Here is a poor pic of the fuel tank support deck I made a while back – the bottom is 1 layer of 1708(+/-45) and a layer of 1400 (0/90) with a 3” strip of 9 oz cloth in the edges. The top is a single 1708. All vac bagged together. The edges of the ¾” coosa core are beveled from the bottom at ~22 degrees so the top and bottom glass comes together for 1” all around the core. The glass on the sides is also sloped at ~22 degrees to generally match the deadrise where it meets the hull down the sides. I shaped it 2" narrower forward so that it just barely touches the keel but will be epoxied down on the sides. It is pretty light and very stiff.


The original was just a ¾” sheet of plywood with some 24oz cloth slopped on it. It was not fitted to the space very well and was completely waterlogged (>30+ lbs even after sitting on a trailer for 10+ years)

[martin]

Fantastic work... Nice electrical schematic..I just may have to borrow it

[FLexpat]

I hadn’t realized how long it has been since I posted to this thread but, between parents and kids, a bunch of stuff kept me from doing much over the last year. Finally slipped out to boat for a couple of days and started back at it and am also posting a few things I had not included before.

Finally finished up the engine beds by putting the motor mount risers on them. Used 4 layers of 1808 getting progressively larger with each layer. Now I won't get water standing outboard of the engine beds.


Made a pipe chase for the drain from the forward fishbox and glassed it to the underside of the fuel tank support. It lines up right next to the keel. I hate hoses and stuff laying in the bilges and I don’t want that box draining to the bilge so a hose from the box will go to a macerator pump mounted in the engine well. I wrapped PVC pipe and a couple of aluminum angles with poly sheeting for a mold and put a couple of layers of 1708 onto it, popped it off the mold then epoxied it onto the underside – it seems like it will work pretty well and the inside is about ¼” larger than the hose to the macerator.


Cut out the starboard side of the deck. I left a 2-½” lip all the way around to bond the new deck to since I want to keep the edge features (hatch lips and gutters). About 2/3 of the core was plywood squares and about 1/3 was balsa; it seemed like the plywood was forward by the helm, along the hatch lips (maybe that was plywood?), and aft by the motor box while the balsa was mostly outboard and midship. It is pretty clear that the pedestal seat mount was the primary source of water and it migrated aft. It seems that plywood makes a much higher quality mulch than balsa but they were both pretty bad although the balsa was still ok right by the scupper gutters where I cut the deck. Maybe the carpenter ants just like wet balsa more than wet plywood and left more for compost? Before I put the new deck in I will seal the lip edges where the wood core is still good and I will fill with glass where it is rotten. I am thinking of just using some 3/8” thick preformed strips (from McMaster) and driving them in with epoxy to bond after I finish scraping the mulch from between the upper and lower skins. I noticed that the upper and lower skins are roughly the same thickness. All this is interesting to me in that it is NOT very consistent with the 1973 Boating article with info about the about the construction of the 23. The Potter putty on the stringers was mostly intact but broke off pretty easily. Over the years we have found pieces of putty in the bilges (it seemed like a lot) and I took out the lower skin thinking I would find the source but it didn’t look like too much came from this side. Like others have noted, the holes in the stringers for foam had not been sealed. I dug down in several places and the foam seems dry so far – I even stuck long screwdrivers all the way in and they came back dry but I will be sealing those holes. I was surprised by the foam outboard of the stringer but it was dry too. The stringers are definitely not parallel with the underside of the deck – the putty was only ¼” thick by the fuel tank and almost an inch in other places.

[Vezo, Part II]

Hey Mitch, LMAO and frying my brain reading that! Are you in Fla? Give me a call!

Michael.

[FLexpat]

No, I didn't abandon this project - just another year of not getting much done with lots of stuff (Irma, daughter's wedding, parents, etc) preventing me from actually getting out the tools in FL. So I decided to take measurements, build a few parts in Utah, ship them to FL and install them in the few spare minutes I have when I'm there (Thanksgiving when I was not happy with football scores). Made hatch lips in a mold I made from measurements of the curve of the stern cap. Used Duratec for the mold surface, waxed it and put PVA on. Wiping or spraying PVA with a spray bottle does not work for me - on the curved hatch I used a cheap Harbor Freight touchup gun at 90psi for PVA and it works great. Gelcoated the mold and laid up mat, soft cloth, and then 1708 in vinyl ester. Thinned the gelcoat 25% with styrene and I was happy with how it sprayed - wife was not happy with the smell in the garage that wafted into the house.

Pic of part and mold is after I cleaned the PVA off.


Made recesses in it for flush Gemlux hinges. 3D printed plastic pieces slightly larger than the hinges to make the hinge recesses.


Rough glassed it in. I was really surprised at how hard it was to deal with the curve of the cap...


Mold for curved hatch. Tried a few new things; picked up wax fillet tools on ebay for $25 and a bunch of wax fillets so I used that. Only put Duratec on the wood parts of the mold - just waxed the whiteboard when I waxed the whole mold. Seems like it will work better - the finish on the fillets is better than on the hatch lips. I already know that gelcoat releases very easily from it...


Discovered that rebuilding a boat in a Legos format is really hard! Matching the curve of the stern cap from measurements and building parts 2000 miles away is a royal pain when it comes time to install them. Learned that the 1/4" whiteboard material from Home Depot is great for smooth finishes on molds but it warps if you build the mold and let it sit in the wrong position for too long. Spraying gelcoat in 6% humidity means no tack to the finish after 24 hours (good and bad). Discovered that letting gelcoat sit for 2 weeks in the curved hatch mold without glassing it means you get to redo it because the gelcoat shrinks and pulls off the mold. I wanted to redo the corner wax fillets on that mold with a smaller radius anyway though.

[ohreally]

Originally Posted by martin

Fantastic work... Nice electrical schematic..I just may have to borrow it

Borrowed (with pride)