Not many pictures today. Finished the main wiring in the boat, did a full power test and no magic smoke was released. Drive, rudder, pump systems are operational. Need to work on solenoids and gun boards and then we'll be 100%. Test fired guns, so far so good. Need to spend a few hours just sitting out there pushing the button dumping BB's across the garage. Test it to the point of failure and rebuild to work it again. Hopefully I'll have pictures next time.
*oh no, I can't imagine it at all without pictures! whatever am I to do!?* Good to hear. weapons testing is fun. any chance you could just set a metronome to do the shooting for you?
I probably could easily enough. I'm lazy. Will be just as easy to sit there watching Star Trek on the garage TV smashing the switches as fast as I can until the gun is empty. Just need to put a few mags through to prove they work in the boat with the magazines bent, etc. I'm gonna be a big baguette with lots of krauts trying to take bites. I'd like to put on a 1918 General Foch's France style fight, not a 1940 Fall of France style fight.
On hold until I get some more XT30 connectors. I wanted to make the systems in the boat universal with other boats, which meant no dedicated wiring soldered to bits. I want the wiring in the boat, not on the components if that makes sense. If a gun board goes, I don't want to worry about leads being too short to transplant into another boat. Made cannon up-tubes and magazines. My plan was to make the front guns load from the opposite turret. Aka B turret's magazine fills are inside of A turret. Worked out well I think. Not quite done but having some lower back issues after manhandling a Subaru transmission yesterday. 4EAT's are deceptively heavy. They're also super tall so if you don't have a 2 post lift you are in for a fun time actually getting it out from under the car/back in. I am never doing that again, Subaru can keep their 400~lb transmissions and head gasket stop leak. Picture time! Gunboard in a 3d printed tray and potted with E6000. Test switches, same deal as gun boards. Going to have a wooden tray in the nose of the boat with the test switches and gun boards mounted so the whole firing system can be removed if necessary. And of course the individual components are all isolated and can be unplugged/unscrewed relatively easily. Also made sure that if necessary the gun test switches can be isolated and the solenoids plugged directly into the firing boards. Test fitting solenoids to B turret guns to try and get an idea of what exactly I'm dealing with here. The nose of this boat is massive, but I quickly filled it with gun junk. Need to remove half of it, if you listen to @Kevin P. my boats dont really need these parts anyway they'll just go 5 out of control before I can use it all. Flipped B turret solenoids around to face forward, you can see some mag routing "underneath" the solenoids. Used standoffs made from multiple layers of 1/8" ply to maintain downhill slope from fill to gun tee. It is a mess in there. Not sure how to make this look any better to be honest. This fits in the boat well, but I need to do something with the bow pump. I was hoping it would sit in the space between solenoids, occupied by the accumulator tanks, but no dice. It sits right in the way of the A turret solenoids. I will adjust. Fill tubes in barbettes. Need to disassemble the whole shebang and add magazine caps to the other 3 magazines. I am running "big tube" for everything, aka 1/8" ID tubing. Figured why not. Anyway, that's it for now. Waiting on XT30's to show up from Amazon and then that should be about it for Jean Bart. Quickly running out of things keeping her at the fitting out pier. She should be "finished" by the end of the week at this rate.
I believe I have tried to impress upon you the necessity of making sure the boat will remain under control for grater than 45 seconds into battle Looks good though. Few considerations if you haven't done so already: Have you tested out one of those guns yet? I generally will test out a new gun design outside of the boat first to make sure it's performing as desired, then replicate. I'd probably go 1/16" hose to the mag, add magnets, give one a test whirl before you go through the trouble of reassembling on the deck piece. Makes execution of design tweaks much easier. I also pressure test any soldered tanks beforehand under water, prevents the headache of trying to find a leak once you have the whole system assembled.
I take all ribbing as constructive criticisim. I have test fired one gun for about 4-5 magazines worth of BBs. All soldered connections have been pressurized and tested. I'm having a tiny issue with my home made 1/8" barbs proving a bit slippery for my clamps. Keep blowing hoses off. Shouldve used a larger material to provide a tighter fit. Will remedy. Planning on magnets. Not quite finished yet. This was mainly a full test fit to see how we'd squeeze it all in there. Will double and triple check all connections, unions, soldered joints, etc. I use slightly soapy water in a spray bottle, spray and look for bubbles. I have been trying to draw on what Ive learned this past year to make this boat good. Ive already learned even more to apply to Courbet and future builds. I wont let you guys down I built Dunkerque in 27 days from plywood to boat, mainly to distract myself from my own problems. In doing so, I found out that I actually really deep down love building hulls. The time I've taken to try and make this boat better than anything I've built previously (All the way back to the Doria) hopefully shows that there is a resolve to make sure this one works
The subaru owner picked the car up today. Hopefully it stays put together and functioning. No warranties implied. Tomorrow need to do the magazine caps on those 3 gun mags, wrap them in the vinyl to protect them from BB dings, and solder XT30's for solenoids. Need to make tiny firing board -> test switch -> solenoid pigtails. Trying to make the components completely modular also means using about 2x the connectors needed. Hopefully will have something to post by end of day tomorrow regarding JB progress.
Update: A small issue with the gun board -> test switch -> solenoid setup has set me back while I wait for new test switch boards. Not sure how, but one of the dual sidemount circuits is shorting across the test switches. Of course, now it's potted in epoxy, so it's impossible to fix. Womp Womp. The good news is the other dual circuit is working fine, so I'm going to cut that out of the block of epoxy and use it in my Suffren. Since I'm on hold electrically, I spent time prepping the hull for sheeting. When you build a wooden hull you want to make sure you blend the ribs into the subdeck+deck rim to give the balsa something to grab. Sharp joints where the rib meets the subdeck will be impossible to sheet properly. So you want to blend them together. Also, sand the ribs in the bow so that way they all blend as they move aft, which will once again make it easier to sheet. I also painted the deck rim to match the decks and worked on mounting the dummy barrels in the main turrets. Still need to remove the dual sidemounts and solder on the magazine caps, but I'm thinking I'll handle that tomorrow. Also worked on JB's carrier some, needed to hit some areas with stain and urethane to keep it from warping/getting funky with moisture over time. Sheeting this weekend (hopefully) with sea trials tentatively the following weekend. Don't have much to show pictures of, so here's a pic of the JB and Suffren sitting where the French Fleet feels the most comfortable (on top of the trash can. Get it. Because everyone is going to make jokes about how French boats are trash) showing off the JB's freshly painted decks. Til next time.
I did something similar in my Deutschlands. Accidentally swapped a couple of leads, so that every shot to one side was a short and blew the control board. Lesson learned: double-check your wiring, then get somebody else to triple-check it, then bench-test every function. Then, and only then, is it safe to epoxy.
Did some boat work today. Worked on the magazine caps for the guns and vinyl wrapping them to protect from damage. Also did hose work. When I started JB I wanted to keep the cannons as modular as possible. Originally the plan was to use 3d printed BIC style cannons in self-contained dual mounts. That got tossed out the window almost immediately because I wanted something that was a known quantity and would work, so I went with a traditional cannon. An unintended bonus to soldering the breech elbows together and mounting the solenoids to the cannons directly is that the two cannons essentially mount as one unit. 3 screws and the dual sidemount comes out as one whole unit, solenoids and all. B turret guns finished. Still need to do one mag cap on A turret and gas lines. Pic just showing the down angle into the tee for B turret. Oof I just realized I forgot the magnets for the Tee, will handle that later. Need to wrap this up ASAP and get her in the water. The April battle in NC is quickly approaching...
So, an issue I just ran into with Jean Bart is the discharge rate of the batteries being used. Under load, I am noticing voltage drops from optimal 12.8v using the popular LiFE cells. This prompted some research. The square cells that some use only have a discharge rate of 2c, so 2xcapacity. 20ah bricks leads to a 40amp max discharge rate. The cylinder cells are even worse, they can only discharge at max around 15amps. This may not be terribly noticable under normal circumstances, but in a 6 foot canoe with two brushless pumps it was immediately noticeable. Pump A runs on a throttle and pump B on a toggle. I could engage A at full and clicking B on would kill the boat. Throttle down both, boat would restart. Kick B on and I could slowly throttle A up to max but you could hear both pumps motors slow down as the voltage dropped. With just 1 pump running the boat goes from 12.8v down to about 10v. With both pumps, it hovers right above the ESC cut off voltage of 6v. All 4 3.2v life bricks in the boat were freshly charged right before this pump test. So, fair warning. If you are running brushless or high capacity brushed, you may be having ESC issues because of poor battery discharge rates. Video here: https://photos.app.goo.gl/4CPFs6V3yfgZAtVj6
I have 8000mah Zippy packs that can supply 240amp Just need to swap out the main power harness in the boat from a 4 x series hook up to a 4 x parallel hookup.
Some of the cylindrical cells can do a lot better(there is a high discharge 8ah version that looks good), but yeah the 20ah bricks arent the greatest. Ran into that in the Bismarck and didnt want to buy new batteries so just turned the pump down a tad. Probably only an issue on dual pump boats or hot single pumps. LiPo discharge rates are attractive.
Yeah I'm just glad I have the zippy packs lying around. I loaned 3 of them out in exchange for these bricks. Will set up the boat to run on 4 of them with top-off charges whenever possible between sorties and definitely between battles. Would like two have two sets of four but not quite in the budget for spring time, should be able to pick up a few more before NATs so I have a complete spare set.
