So, I figured I'd start this thread because the build effort will be running parallel with my Courbet. I've always liked HMS Erin as a beamy little allied slugger, but there is no commercial hull available. So, I started looking for plans to build a wooden one. This lead to my local rookie requesting an Erin as his second hull (He's just about finished fitting out a QE that belongs to me and is going to be coming with me to whatever battles I attend in 2020) and when you're making two hulls you're pretty much right on the line for time effectiveness to just make a plug and mold them. After talking to Steve A in MD he said he was in for at least 1 Erin, so looks like I'm making a plug. I only found one easy source for plans, being the former Strike Models, but I'm pretty sure they're Goff plans and I've had bad luck with them in the past. So I got in contact with a 3d modeller who had modeled Erin for a game and bought a copy of his model, which was made in 3d MAX and required someone who had access to that (very expensive) application. We (local rookie and I) converted it into an OBJ, trimmed off the superstructure and other details for later, and then chopped the hull model into 14 digestible bits for my pair of I3 printers to chew on. Loaded into Fusion360, the hull is accurate dimensionally to the IRCWCC shiplist specs of 46.67 LOA and 7.67 beam within about 2%. The whole ship then had 1/4" alignment holes sent through it to make sure it all lines back up properly, and now I'm waiting on the first chunk to finish printing to see how it reacts to West Systems heat for use as a plug. In the pic below you can see the models cutouts for anchors (which will be filled post-printing) and one of the alignment dowel holes. The first 4 chunks of the bow and the last chunk of the stern are not split port/starboard because they fit on the build plate as-is, these pieces will be the keystone pieces to hold the ship together with the dowels. The remaining 9 chunks are split port/starboard, hard to fit a 7.67" wide piece on a 7.8" build plate. I'll return with progress pics of Chunk 1 in about 5 hours, theoretically.
Why not just make ABS ribs and assemble the frame like a wood hull? Most of the fiberglass in a molded hull is cut away, kind of a lot of material in the land fill.
I thought of that, but I don't like it's potential durability. I'd be worried about the ribs breaking along layer lines. Also I lack the print area to be able to print the whole ribs at the ships widest point, meaning another potential failure spot where the rib halves would meet in the middle. If I had some fancy setup printing crazy materials it would probably work, but traditional ABS printing on my cheap FDM printer I don't think would hold up.
An acetone vapor bath significantly reduces layer-splitting, not to mention you can use ABS slurry to weld pieces together into a very strong whole. The 3d-printed superstructures I've used held up very well under fire, and that was before I learned how to do vapor baths. I hope to test the theory with one of those 3d-printed transports at some point.
Yeah, done all that. Still blown chunks out of it. Superstructure bits sure, but I'm not ready to spend all the time on a hull to need massive structural repairs after 2 battles.
First 2 sections are done. Bow section 3 is the largest single print and barely fits on my glass printer bed. It's also the longest single print at 21 hours. My printer is pretty dialed in and these long prints don't worry me much. My only complaint is the need to section the hull, I think my next printer will be something like the Creality CR10 MAX with a 17"x17" build volume. Could print a Yamato in 4 maybe 5 chunks vs a small dreadnought in 14 chunks. Anyhoo, some progress pics. Tons of finish work will be needed to make a usable plug but this is my first time ever trying this, I can't imagine it'll be much worse than building a plug from scratch via wood. The anchor holes visible will be completely filled during the finish process. The hole below that is one of the alignment dowel holes that runs throughout the whole print. Quarter inch dowels will be set through the hole marked taken back out cut to be as flush as possible and then sanded down flush with the plastic surface.
Another update to the kitchen table Erinometer. We're looking at accumulations of 14 and a half inches so far and a projected forecast of 46.75 inches total by the end of this winter weather event. The square geometry you can make out in the middle of the hull is the ship's armor belt. While British battleships don't traditionally have pronounced armor belts to deserve a stringer The 3D model I am using modeled it. So it shows up on the 3D print, it's maybe 1/8 of an inch over the actual surface of the hull. The ship's stern did not have a very pronounced skeg so I figured if she would be usable as is and no non-scale modifications were made. Only time will tell.
Another Erin update. Due to an impending filament shortage, I'm printing part #8L instead of 7R due to it's smaller size. After the current 5 hour print is finished, I'll only have 7R, 8R, and then the stern cap part #9 and the hull will be fully printed. Then it's time to post-process and filler, sand, filler, sand, filler, sand, paint, sand, paint, sand, more filler, sand.
Very cool. Suggestions from my past plug headaches: Don't rush through alignment. Taking extra time to get everything flush saves a lot more time to fair in discontinuities I would spray the whole thing once with primer, then apply a liberal layer of high-quality filler over everything (100% coverage, no paint showing) Once that dries, sand until the raised printed portions become visible After that you might be good, just spray it with a heavier paint a couple times and move to mold prep. You'll have to decide about the armor belt, could be saved or faired in
