I am Starting the pre prep on the Yamato so that it might be ready for water testing by the second battle of next year and sees combat at the last. working on it as i either wait for the Kongo to dry or advise on what to do with it next. first thing is solenoid or mavs? which is more reliable second is water channeling foam, wood, or combination. i think a layer of wood on the bottom two rows would make it more resistant to warping and bending as the yamato weighs so very much. batteries go for the heavy lead acid so i have some removable weights and 12v of power or get some LiFe cells for the same amp hours at less weight and 6v.(not dumping 500 in batteries to get 12v) launch/recovering rig is a must going to go with some reinforced pvc to keep it light but submersible. 2-2.5 inch props powering only 2 or power all 4? going brushless with bigger motors than what i got in the Kongo now as 26 pounds 1.5 prop gets to 24 at 65% power mostly due to a dead spot in the start power. direct drive with stainless gears seems the only way to keep things from slipping to much with that torque. will probably use the same 50A boat esc i have in the kongo with the watercooling actually installed just behind the props.
Solenoids - all day, every day (for a ton of reasons). Look inside any truly competitive boat if you don't believe me. Water-channeling - Balsa covered with a layer of fiberglass. Batteries - You can probably do ok with lead acid but LiFe is really a better chemistry. 3x-4x the cycle life, flatter discharge curve, higher energy density, and specific energy. They do have a higher up-front cost but if you amortize that over the lifetime of the battery it isn't a big deal. If you want weight buy a sack of lead shot and build your own custom weights so you can distribute it where you actually want it not where the battery will fit. Lots of extra weight in a battery that is way over-sized and you'll never use doesn't make sense when there are better alternatives. I don't think advantages from 12v are worth the disadvantages from lead acid. Launching/Recovery rig - yup, or get a chiropractor with really good rates.... Props - only power two, drag disks on outboard shafts. Spend the time playing/tweaking/experimenting to get it turning the best you can, it will be worth it. I'm not sure what you mean "direct drive with stainless gears". Gears are the way to go in probably 90%+ of boats. Use stainless steel if you want but no real reason that you need to. Steel, Al, Bronze/Brass, and plastic gears can all work too, nothing wrong with stainless just they might not be as easy to find or worth the extra $$. (steel gears rusting shouldn't be an issue, assuming you lube them and let the boat dry out when you're done with it. Lots of guys have been using steel gears for years and years.)
going to go with the 20amp hour prism batteries 2 be enough in series to keep it or do i need more amp hours for a day?
How much battery you need really depends on how much current you're drawing with your pump(s) and drive motors. I'd guess that 20Ah @ ~6.6V probably isnt enough for a full day of heavy battling but you could probably run that for a single battle and be ok. The pump is typically the big draw, and you'll want/need a decent pump if you're wanting to have some dual sidemount fun. Motors typically aren't too bad, but for driving ~60lbs on two large props they will be drawing a decent amount. It's probably worth it to buy one set of batteries initially so you have them for the build and early testing, once you get a better idea of what type of current everything draws (not just on the bench but actually in the water/pumping heavy) you can buy a second set.
looking into motors i might need to get a third battery just to get the amp hours i need for the low KV high watt high weight motors that massive amounts of torque would be useful on. on the topic of construction and windows. does in the rules the flat section on the lifeboat hangers near the rear facing forward need to be penetrable or is that an allowable hard area.
on the guns it is best to do 2 different bottles one for the forward duals and one for the aft triple? or do an accumulator on the rear triple. will have at least one 20z bottle as i seem to have plenty of room and the weight is always a good thing when you need as much as this will. going with spartan solenoids.
You'll get more flow out of two smaller bottles and two regulators than you will with one bottle which will help performance. I'd probably go with two 7-9oz bottles. Of course you get twice the failure points that way but if the systems are seperate you also get some fault tolerance, one hose blows and you only loose half your guns not all of them.
2 smaller bottles sounds like a plan. ordered some motors and will be ordering the parts i need to make the stuffing tubes as the last time i ordered i got far to large of a diameter tube for the bushing si ordered. plan on putting some zerts on the tubes to make them much simpler to maintain.
That's probably the easiest/simplest dual bottle setup. If I was going for pure performing I'd put one gun from each dual turret on each bottle and then run both bottles through check valves to the triples. It's a lot of plumbing but improvement to the dual sidemounts might be worth it and the triple sterns would benefit some as well. Then again it's 1/32" balsa that you're up against.... How much do you need to compensate for?
I use 1 large 20 oz bottle to power all the guns. I have an acumulator 2 in tank for the stbd dual sidemounts another for the port dual sidemounts and a 3 inch accumulator tank for the sterns. I use the Mavs ansd poppets. All guns fire well and hard. I use 4 6v 12amp each for 6v 48amps. Powers everything for a loong t I me. I have Traaxis gears with universal connection and use 2 inch props.I think they are a little bigger than that.
ordered 2 inch 25 pitch props from bc as well as more mounting stuff. Yamato will be floating under power at least by end of december. Kongo just needs aft deck sealed back up and everything ran again and then weight tested. it might have full SS next battle and Yamato might be in trials that day as well. Will be making a couple trips down to BC shop to get some advise and where bits should go and how bits should go in.
PARTS HAVE ARRIVED! will be putting the props and motors in over this week as well as the subdeck and deck so i can do some water testing to find out if i need to get another battery or 6v will be plenty for the motors i got. putting zerts on the stuffing tubes to make greasing simpler.
well i just realized i am lacking in the build pictures. rule one need more clamps. something like 60 clamps there comes to around 10-15 pounds worth of them going to go back around with micro mix maybe some flox and get a good solid bond with the deck rim
well... having pudding installed could help keep the shafts greased... and a little snack during service... lookin good!
Ordered the rudder set from BC to reduce the amount or possible things to rot over time. installed the the zerk on the stuffing tubes installed both drive props and started to work on the outlying shafts and lost the last bearing so they will get installed once i get more later
