It's been a while since I last updated and lots of progress has been made. Going to try and finish before the August battle Filled in everything Messed up a bit but fixed it using 1/32 balsa, CA, and blind luck Glassed and shiny. Tubes soldered and ready! Glamour shot! Did a bit of digging for the motor mount. No clue how to fill in the gaps under the motor mount to let water flow but considering free form air or featherlite Propshaft holes drilled and fitted somehow Quite a nerve-wracking couple of minutes ( roasted the brushes on my dremel too) but I managed to cut them out in the right spot Guns mounted! Will change the mounting method later but eh, good enough for now. Underneath Chewed up my boat a bit and poked through the bottom with my dremel so the 1/32 balsa saved the day again Decks rims cut Another glamour shot!!!! Tested the clearance of the homemade props. Close enough. Since I want to be able to remove my motor mount i used hot glue to tack them down for now. Made a little sliding thingy for the deck Rudder constructed! Rudder servo mount secured! Choked a bit on lead solder fumes but managed to get everything wired up. Nice shot of how it all fits. Made the rudder arm thingy. Made the bearing surface for the other side of the propshaft. Since I'm too poor for solenoids( and I have no room in the stern) I Macguyvered a firing system for one poppet out of some wood and my trusty hot glue. My boat keeps looking more and more like a 5th grade art project. ALL WIRED UP! TIME TO TEST!( Duct tape armor was temporary. It didn't matter anyway because when I put her in a pool she started flooding heavily from the bow.) Oops...I think I burned my switch out. I proceeded to burn through 3 more switches until I gave up my test. Guess Pola will get a real trial by fire at the next battle. BEAUTY SHOT I gave up testing and decided to sheet My tools/toxic fume generator prepared Wow it turned out better than I thought. Bit sticky though. Another angle. I got lazy and decided not to grind the rudder into some sort of modern art sculpture so I just waterproofed it for now. The way the light shows through is quite nice. My next goal is to get a better firing system, make my bottle mount, secure the guts, get some plastic tubing for the barrels, make the superstructure, and do a couple more things hopefully before the battle.
More progress has been made. Internals prepped for soldering. Pardon the mess. Little messy but everything's modular and I can swap stuff out pretty quickly Main Power distribution thingy that I made. Hopefully it works. I'm switching to solenoids since I don't have enough room in the stern to put in poppets. Also what kinds of firing boards do you use? Im using a reciever on/off switch but it's a bit slow. Switched the cannon mounting method. Hopefully this one works better than the other one. Drew out the turret arrangement. Going to scratchbuild them from craft foam since its so easy to shape. Starting Finished. Still need to find a way to non-invasively secure my cannons so I may try using tubes soldered to a brass piece that slide over the barrels. Heh. Time for Pola's maiden voyage. Hmm. Seems that the battery makes Pola list to port. Guess i'll have to work on balance. Maybe I should add bilge keels too? Guns also seem to misfire most of my shots so it may be a feed problem. Turning...no clue how good of a turn circle that is. Should I make the rudder throw a bit longer? Should I try to increase the performance? Also, how's the speed looking? Stopping seems quite good. Backing up sends water cascading into the stern and it flooded all the way to the motor mount. Any suggestions for sealing my deck? Also since I still havent found a good substance to fill the areas between the ribs ( getting featherlite shipped is horrid.) the water just stayed in the gaps, forcing the ship further into the water. Considering concrete sealant at the moment( I think resin looks nicer but it may be expensive). Also I think my 3/8" deep water channel may cause some problems... Anyway i'm going to move on to superstructure soon. What materials do you use and how does it hold up? What kind of hot wire cutter do you use for styrofoam? I was considering using the craft foam again(1/4" stuff for the structure and the thin stuff for decoration) but im not sure how durable it is. How do you handle the intricate curves some ships have( like the area around the stacks)? Is there any other advice you guys have given how the ship is right now? Any other miscellaneous comments?
Build is looking good! For firing switches, I like Pololu switches. They're cheap and fire fast. This ones good for single solenoids. https://www.pololu.com/product/2802 This one is good for doubles or triples. https://www.pololu.com/product/2803 Your speed may be a little slow. Can you add a little pitch to your props? How much rudder throw are you getting?
Very nice work on your Pola and congrats on getting it on the water. It looks a bit slow to me though. You can hopefully address this by increasing the pitch on the props. Another option would be to replace the SLA battery with a higher voltage lithium which would give you more RPM's on the motors (but watch your max voltage on your ESC if considering this). This would shave some weight off also. Since it appears you don't have much weight to spare. I'd recommend foam blocks for the super. The foam I use (Yoga blocks) cuts quite nicely on a band or scroll saw. You can look at my Mogador and Barham builds to see examples. Your next step though should be pulling everything out of the hull and address the water channeling. As is, your boat is going to collect quite a bit of water before it starts flowing to your pump.
I'd say i'm getting a little less than 45 degrees on either side when looking astern from underneath. Kinda hard to describe so I drew a diagram
Nice build. A few tips 1) For water channel, I'd recommend 1/4" balsa to fill in between the ribs, try to build up the whole area aft of the motors a bit (since the pump can't pump out water from back there), then along the rest of the length add a layer to the bottom and leave a channel down the middle about 1.5-2" wide. Right now the frames look like they will collect water between them, which is not good 2) Deck seal, you can use silicone on either the deck or the subdeck surface. Lightly sand one surface, clean it off, then put some silicone down. Either lubricate the other surface or use plastic wrap to keep the silicone from sticking to both, then put the deck on and latch it down until the silicone dries. Not the best method, but given your configuration it is probably one of the only options 3) Try to ditch the SLA for Nimh's or LiFe batteries, they will save you weight. I'd recommend two of the 10Ah LiFe cylindrical cells from battery space per battle. They will make the ship more nimble and can give you all the amps your heart desires. 4) What pump motor do you have on there? It looks pretty serious for a cruiser 5) Turning isn't that great, I think you are losing a lot of the thrust over the rudder based on where your props are located. This is a hard one to fix. If your local rules allow fishtails/concave sides you could probably improve turning a bit, but having the props high on the side make it hard for the rudder to catch the thrust from the outboard prop when you turn 6) For gun feeding, you can add rare earth magnets to the T's. Right now the angle of the magazine going to the T is probably too level, so the BB's are sloshing around when you fire. I use the 1/2" by 1/8" magnets opposite the port for the magazine which holds the BB's on top of the pin. 7) It might be slow, but you need a speed course to really tell. To increase speed just increase the pitch on the props slightly and you should get there no problem Hope this helps, still a very nice looking boat
1) Is Epoxy resin or the concrete sealant viable? Or does it just add too much weight? 2) What is the "best" method in your opinion to seal the deck if you start on a new ship? 4) I'm using the large BC pump with a 540 Tamiya sport tuned motor so yes it is way overkill. Maybe I should change it? 6) By opposite the port do you mean you glued them on the "top" of the "T"? Do you drill into the "T" a bit or just glue it as it is? Also should I try to have the boat sit lower in the water or is agility more important in a cruiser? Switching out the battery would mean I have a couple more pounds to spare. Dang, I regret not finishing the water channel before sheeting... Lessons learned.... Thank you to everyone for the support so far though! :v
I listened to your guns fire, the solenoids are staying open for way too long (not sure if you are doing that or the solenoids are doing that). I'd recommend the BC single firing board ($20) or their new dual firing board ($25, could be used on a different ship in the future) You will want to wire in test switches to fire each gun independently from the boat in order to tweak the guns, BC offers a board with switches, or you can buy switches somewhere else and do a couple more solder joints. You take the signal output from the gun board and put it to the NC position on the switches, take the lead from the battery and connect to the NO, and run a wire from COM to each solenoid. Make sure to use diodes across each solenoid as well. Here is an article that has a picture, I typically do the switching on the negative side but otherwise the diagram will work http://www.southeastattacksquadron.org/howto/TripleTests/TripleTestCircuit.htm
1) concrete sealant is way too heavy. You could use resin with sawdust or some other type of filler to reduce the density, I think 1/4" balsa cut down to fit between each rib would work well. I'd weigh the boat now and set that as a max weight. If you change the batteries you will get some savings, but superstructure will still weight something, and once you put resin in the bottom it is a pain to remove. If you have about a pound of net savings to work with then resin might be OK 2) The best seal I have used is magnetic strip tape, since it provides a force and seal along the whole length. It works out to be 1/8" thick, so it goes well with 1/16" fiberglass deck. I will use it on several of my next builds. There are a few other methods that have been used very successfully, the Nassau in the 'warships in detail' section of this site is essentially a submarine 4) The motor is probably overkill, a generic Johnson 600 motor or Mabuchi 540 work fine for a cruiser (or a 380 on a BC small pump). Id say that your motor would be an issue with SLA batteries, but cruisers shouldn't take much damage so might be OK 6) Like this. Glued to the T with Goop or E6000 (super glued first). Slightly lower than directly opposite the magazine so they dont pull BB's up which can cause double firing Stability is most important in a cruiser, so heavy is OK if the weight is low so the boat doesn't roll. Heavier means less margin for error in terms of damage taking ability. Generally the best cruisers are lower in the water so they take less damage and can shoot just above the surface of the water over a long-ish distance. To start, lighter might be better until you get more comfortable with how the boat battles, and it gives you room to add small trim weights to fix the list, see how it runs with water in the hull, then adjust as desired
Move the rudder up closer to the bottom of the hull. It is kind of hard to tell from the pictures but it looks like you have a lot of down angle on the shafts. It might be difficult but if you can get them as flat (level) as possible to move the angle of the props to better wash over the rudder. Also make sure you have lots of throw on the rudder. Should be able to swing nearly 180 degrees then you can back it down a little with the end point until you get your optimal turning. Also, those props. I'd highly recommend going to a steeper pitch. Those look like maybe 18-20 degrees. 25 or 27 is more typical. Especially with gearboxes you can bite more pitch off. With only a 2 shaft ship your start/stop won't be as good as a 4 shafter, so maximizing turning should help you a bit. Looking good keep working!
The shafts are hard mounted and i'd have to remove a glop of epoxy plus a bit of hull to change them sadly. As for the rudder steering, I have a pushrod in there since it's a narrow stern and the big gears are a bit big so i'm not sure what to do.
The shafts look pretty level to me. I wouldn't worry about it. Your issues lie elsewhere. Mainly get some more pitch on the props and more throw on the rudder. Lengthen the arm on the servo. That will increase the range of movement on the rudder.
Right now Pola is 9.3 lbs out of a total of 12 lbs. Should I make this my max weight? Seems a bit light.
What is scale weight? Usually a little above this is a good place to be. If you already have west systems use that with balsa filler. Glue in strips of balsa and west system the crap out of it. If you need more weight fill some space with shot or bbs. I've used LEGO gears before in tight spaces. Lots of sizes available and they are cheap if you get them as bits on ebay.
