9/22/2023: The model went in the tub today and was ballasted to determine the weight the lead bulb will need to be 25 pounds (deducting the battery's weight) putting her about 1/2 an inch from her painted waterline.

11/27-28: While tinkering on a 3D model of Constellations 2nd cutter, I was giving the idea of making Pride's 25 pound lead bulb some thought. I decided I didn't want to get the tools and materials to melt and cast lead. Regardless, I would still have to come up with a container, or a form. That's basically what I did for Constellation's ballast, using a PVC pipe as the container. Why not 3D model precisely what I needed as a container for Pride?

I started by making a ball in Anim8or with it's surfaces facing inward. Then I looked up how to calculate the volume and found a nice Ellipsoid Calculator where I could plug in numbers in millimeters (what Anim8or uses) and get an answer in cubic inches (what my brain uses). Lead weighs .41 of a pound per cubic inch, meaning I need a volume of about 61 cubic inches. Playing with the numbers on the site, I settled on a=50mm, b=105mm, and c=45mm, giving me 60.62 cubic inches, or 24.9 pounds. The weight of the fin, the resin shell, the epoxy fill, etc should put this really close to 25 pounds.

Adjusting my 3D ball into an ellipsoid of those dimensions gave me the inner surface of my bulb. I copied that enlarged it, and flipped the surface to face outward, giving me the outer surface of the bulb and making it slightly over 1/8" thick. I closed the gaps between the two surfaces, and added a slot and some structure for the fin to sit on. It wasn't going to fit in the 3D printer full size, so I divided it into quarters and I could print 2 parts, or half the bulb at a time.

Once printed, the pieces will be bonded together to form a left and a right half. I'll fill these with the lead shot, and pour epoxy into each half to bond everything together and make it solid. The two halves will be bonded together on the fin and then a hole will get drilled through the bulb and the fin for a pin, so there's no chance of the buld coming off the fin. The whole thing will get a coat of epoxy outside to toughen up the resin bulb, and then it'll be painted the same Moss Green as the models bottom.

11/29: I printed half the bulb and started the other half over-night. Genius that I am, I didn't check the resin level, and it ran out about 80% through the print, and I had to start over.

With all 4 quarters finally printed, I bonded two each together with resin and UV light to make two halves. The seams will need sanding, but that's not an issue. Now to load it up with lead.

11/30: I sieved the reclaimed lead a few times to lose as much dust and dirt as I could. I didn't wash it because it would take a long time to be completely dry, and I don't want to seal moisture inside the bulb. As long as it's dry, I don't think being dirty will matter. I filled both halves with shot, but it was too cold tonight to pour epoxy, so, if it's above 55°f tomorrow, I'll give it a try.

12/1: I got everything together to pour expoxy and when I went to mix it, the resin was like an old ketchup commercial (hardly moved, wouldn't pour). I put the epoxy in the house to warm up, and will give it another go later.

12/2: Bringing the epoxy in the house did the trick. The resin is still thicker than the hardener, but it it's pretty fluid when mixed, even when it's not above 70°. I mixed a yogurt cup full and still had about 1/3 of it left after pouring, so I propped up the bow of the model poured it into the bilge, filling the tight spots back at the deadwood. Later it hit me that I should have put some lead in there too. I did that, and it all sank down into the epoxy as if I'd done it right the first time.

12/3: I brought the bulb into the house so it would hopefully set better than in the 55°ish shop. By morning it was only a little tacky to the touch. Mixing another batch of about half of what I did before, I poured in some more with the halves tilted a little to get behind that flap for the fin to rest against, and to get it up to the edge. Again, I had some left-over, and this time I poured it and some lead into the bow of the model.

1/20/2024: Still to cold to epoxy the bulb together, and too messy to do in the house, but a couple of folks ask about what going to hold the bulb to the fin. The bulb's halves will get epoxied to eachother and the fin. To prevent the bulb from just dropping off if the epoxy doesn't stick to the aluminum for whatever reason, there's a hole near the bottom of the fin, and corresponding holes drilled partway into the lead/epoxy in the bulb. A metal pin will be captured here so the bulb can't drop off unless the halves come apart somehow.

I'm just about done making Constellation's remaining boats, so I started working on Pride's.

Pride had four boats when I was aboard:

• A lapstrake boat about 16 foot, that sat, inverted, on top of the stern davits and wasn't used in the time I was there. I'll be modeling this one.
• A double-ended whale-boat sort-of thing referred to as the Bequia Boat. This went into storage somewhere soon after I reported aboard, and was brought back just before Pride left Baltimore. I may or may not model this one. If I do, it'll just be a simple double-ended boat as I don't have lines or even good photos of the thing.
• A gray inflatable, aquired maybe 3 or 4 months before I came aboard. I think it got stowed onshore as I don't recall seeing much of. I won't be modeling this one.
• An orange, or very faded red inflatable that was well used and scruffy with paint drippings all over it. What I made below isn't a very accurate model of it, but it'll get the idea across.

5/23: Winter, as far as handling epoxy in an unheated garage matters, seemed to last almost till the end of April and even crept into May; but finally the temperatures and my time have coincided enough that I could get somethingsome movement on these models.

It seems the plastic egg deformed a little from the weight, so the two halves won't lay flat to each other. If I do this 3D printed bulb thing again, and for you following along that might be thinking of using this method, I'll will put ribs inside the bulb to stiffen it, and maybe fashion some sort of cradle that supports the bulb so it doesn't try to flatten out as the epoxy and lead set-up.

There were also pockets in the bulb that resin hadn't gotten to and I could hear the shot rattling around inside. If there's a next time, I'll mix shot and resin and pour it in layers to ensure the resin gets everywhere it needs to be and everything will be solid. What sounded like the biggest of these pockets was behind the flanges to support the fin. I opened the holes here and poured more resin in to hopefully fill this void.

I re-drilled holes for the pin that will keep the bulb from sliding off the plate, and cut about a 3 inch length of 3/16" brass rod for the pin. I mixed some very fine sawdust from my band-saw with the epoxy to make a paste of it, and buttered both sides of the bulb and the pin holes, placed the pin, the fin, and put the other half on.

I used a sliver of wood as a wedge to hold the seam closed on top, where the fin enters, as close as I could, making something of a gap at the bottom. The epoxy butter filled this in fairly well, but the seam's open almost all the way around, which I'll fill with more epoxy butter.

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