It's been a while since I was able to work on Tiger. Life completely interrupted; but I've been able to find a few free hours. Unfortunately; I think it's unlikely to see her finished by NATs. As @Commodore recommended, the aft deck is the support for the main deck. As a result, there are no cross-bars to get in the way of maintenance.
Looking forward to seeing how you will maintain strength width-wise. Substantial crossmembers on a printed boat have proven to be key to ensuring proper anti-crush strength. Not a whole lot of provision for a good deck seal, which can be the critical difference between a competitive boat and a lunch menu item boat. Also, lots of waviness in your basic hull body. Bad lofts. I'd recommend using the zebra analysis tool to highlight these areas if you can't easily identify them. You honestly might want to consider how far you want to progress with this model vs starting the solid hull body over, as these errors in the earliest phase of design will be extremely difficult to remove as you go further. Sad to hear it wont be at NATs, I was looking forward to the El Tigre WWE fight. Hope to still see you in something, regardless
Good questions, my thoughts: Crush concerns - I’m using the experience from Deutschland as guidance. She had one crossbar only, at the deck step. In battle, she was TBoned by a full speed Iowa that went to dead stop. Now, that ship is thinner, has one more cross beam, and is 10+lbs lighter. What I will do is re-re-review the rib thickness compared to Deutschland; and fatten them up if needed. I will also seriously reconsider not having a crossbar at the deck step. Deck seal - Yeah, I started with 1/4” deck lip; because it worked on Deutschland. Although that ship used deck screws, and I’d like to explore magnets for Tiger… which would again make her more susceptible to crush. I figured I’d likely thicken it up a bit, so I made sure it’d be a simple variable change later. Waviness - I’ll check out the zebra tool on the outer hull surface shape. I know there is ugly waviness on the surface of the inner hull, but I can’t see why I’d care. > starting over I think I design these ships differently than I’ve seen from ya’lls videos. While, I don’t love changing features earlier in the designs, I have all construction features grouped and organized in the timeline, so it’s not the end of the world for me. I routinely rollback in time to tweak something I didn’t like later. Visiting NATS - I’m not ruling out upgrading Deutschland for fast gun rules. I’d prolly only need hopped up motors, better rudder, and scale down the cannons for BB. My bigger concern is im unclear how deep a Deutschland needs to be in IRC. NTXBG specifies a depth range; but I heard in IRC the depth must be exact… but I can’t find what that exact number is, and I’m sure I didn’t just happen to get it perfect.
Fastgun speeds and violence are a bit higher than big gun. And the crush resistance I'm referring to is not specifically for on-water encounters. Shit happens in the pits, in transporting, etc. I've seen wooden and fiberglass boats cracked in transit. When a 30lb toolbox slides and pins the boat between itself and the truck bed side...that can be an issue. Rib thickness itself isn't the solution, you need something to maintain beam at the top of the hull to prevent from ripping your ribs free from the bottom structure and/or cracking the bottom. You can see the waviness on the outside as well as the inside. Zebra analysis will highlight it for you. IRC dictates that hulls need to be scale within an acceptable margin of error. The rules don't specifically state a margin for hull height, but they do state you need to maintain 1/2" of freeboard at the ships lowest point (as of 2024). A scale hull depth shouldn't be difficult to find.
I think the hull looks good, I don’t see anything that would be noticeable with balsa on the sides. Tiger is very similar to WWI Kongo, on mine I have one cross member a few inches forward of C turret and it causes no access issues, it’s a long boat so plenty of room to get motors and pump aft of the cross member, put in batteries forward of the cross member. I would have at least 1/2” of overlap between subdeck and the deck piece, and have some sort of positive force to hold the aft deck down because of water when driving in reverse. For the cruiser, hull height should be scale, from what I remember of you build it seemed fine. If the boat weighed 5 pounds and had 1/2” of freeboard then that would be pushing it.
The balsa-covered sections look fine. I'm seeing a few wobbly sections around the turn of the bilge, which would not get covered over. It is more pronounced on the inside of the hull, but is still somewhat visible on the outside from certain perspectives. Have you considered doing a mix of deck attachment types? Screw down the aft deck, since you shouldn't need to access it at battle days, then magnet the main deck in place for easier access to batteries, bottle, etc. With the aft deck screwed down, that should provide a good seal and support from sideways impacts and stress.
I should clarify that I make an inner and outer hull surface as separate designs. I don’t just scale the outer hull. So the inner hull doesn’t reflect the shape of the outer hull. That said. I will use the zebra tool to look to smooth it a bit more. Mixing deck attachments - I like it! I will do that. The aft will be screwed down as you recommend. I’ll also lockdown the deck surrounding the cannons too, this gives my rotate tech an advantage. This should give her all the crush strength she needs.
I have done the mixed deck attachment in the past, works fine. Especially screws/thumbscrews for rear deck, where water intrusion is at its worst. In fact, the SJS Graf Spee kit uses a service-only screw down rear deck aft of the deck step.
