My next new boat will be the Seydlitz, with the hull I won in a raffle at NATS this past year (Thanks again BC). This will be my primary regionals boat next year. Fortunately I have Charley's gold standard build to guide my construction. This will be a 6v nominal boat, with brushless drive and a Titan pump. I'm planning to use interwoven props with a single drive motor, probably in the 1300kv range. I'm waiting on a second 1.6" kort prop to arrive from the UK (prop shop messed up one of my previous orders and gave me one 1.7" prop and one 1.6" prop). I have the fiberglass deck from BC, water channeling material, BC pump, most of the electronics, and fittings to make guns. I plan to use BC's new solenoids which I got to see a few weeks ago down in TN. This is a beautiful hull, with lots of hard area. I did a float test last weekend at a local pond as the boat is too long for the bath tub. I tested it at 21 and 22.5 pounds. Looking at the pictures I may have had it trimmed by the stern a little to much. I think my plan will be to build it to 21 lbs, and then add more weight if necessary. My plan of attack will be to start with cutting the windows and installing the water channeling while I wait for the second prop to arrive. Once I have the props, I'll install the prop shafts and motor mount/gearbox, then the rudder post before installing the deck.
Pictures from the float test. These are all at 21 lbs by the scale I have. By testing the hull at three weights I could determine that 1 additional pound of weight will change the free board by 0.094 inches. This test was also used to determine the center of flotation to aid in the building process.
Kevin, Get your drive system installed, and your cannons clearly marked. This is space that you can’t work around. Are you planning a waterproof box? This would also be space that you can’t work around. Your CO2 bottle will take up a lot of space. You will need to make sure that it is not interfering with any gun placement. After you get all of that figured out you can start to look at how it will trim out.
Sounds good Kevin! You will love it, In my opinion of the all the Axis ships I have built this Ship is the best! I would put her against nearly any ship on the water... If you need input on construction for sure let me know
Thanks for the feedback. I have the windows marked and hope to cut them this weekend. I used fishing line to mark the waterline. Here is the bow, with four 3/8' ribs since it is the main target area for the boat. Midships. The entire casement area will essentially be impenetrable based on the space between the deck rim and casement deck stringer. I'll probably write a rule proposal to change this And stern. There won't be much to shoot at back here. I'm still waiting for the props to arrive, but the plan will be to use 32-pitch gears from stock drive products, 1.125" in diameter which should have enough space for the props to intermingle without contact. The props I plan to use are 1.6" korts. I have a piece of aluminum angle stock to serve as a motor mount, though I may need a taller piece (have 1.5" face now). I have the balsa for the water channel, and the plan will be to use Charley's layout. I am a little worried about having the voids under the balsa, but I'll fiberglass the channeling and see how it looks.
I got the windows cut today. Drilled 1/8" holes in the corners of the windows And a rough cut of the windows. I will need to do some touch ups to verify everything is within specs. It's the thought that counts for the casements, right? Too tight for a BB to go through. I cut out parts of the deck for a rough layout assessment. I'm trying to decide if the 2 bricks will be able to provide enough amps for a Titan pump and one brushless drive motor. I think the pump will pull 30 amps at full stream, and I'm not sure about the drive motor. The bricks have a 2C discharge rating which should be 40 amps. The alternative would be throwing in a zippy pack for drive, the boat could probably handle the weight. Any thoughts? Drive motor will be either about 1400kV with 2.7ish reduction driving two props at 6.6v or about 900kV at 13.2v if I use my zippy packs.
Use the Zippy for pump and the bricks for drive, the pump battery will be changed every sortie. The bricks will give you enough for a full battle. I am a high voltage kind of guy so I would try to stuff 4 bricks or 3 if four won't fit.
I've made some progress on getting the shafts sorted out. I chopped the aft keel section off to make room for the rudder and props, I think I cut a little bit more than I needed to. After The plan for the gearbox was to use 1 motor, two shafts, for interwoven props. 1.6" diameter template with the desired spacing The gearbox is a copyright infringement on Ming's design, and im willing to negotiate the royalty claims. Stuffing tubes were soldered together to allow for the flanged oilite bearing diameter I used a Traxxas gearbox plate to allow for adjustment of the drive motor Still in test fit stage. Checking for access with the deck. Slightly different angle. So the plan is to mount the bottom plate through the hull with two 10-32 bolts, and the top plate to the bottom plate with two separate 10-32 bolts. I'm undecided about what adhesive to use for the bottom plate, since i don't think fiberglassing it will work too great with aluminum. I'm considering the E6000 stuff just for the bottom plate, and use West systems and mat for shafts. Any thoughts? The top plate/angle piece will be removable to allow oiling of the motor since the other fasteners for the motor aren't really accessible. Plan is to get it all glued in tomorrow afternoon
I would mount it with Goop/e6000 and bolts through the hull as a mechanical. The torque is kind of scary with brushless and a gearbox, things break that you would not think could.
Shafts are drying now. I went with e6000 and two bolts for the gearbox. Like most things I build, it didn't come out as nice as I planned, but looks like it should work. I cut down the plates a bit. More to follow
I ended up mounting the motor a little off center, here was the first bolt. I decided to put the struts in now as well Glassed the shafts in. Side view
Made some progress over the long weekend. Started with the drag shafts last week. I wanted to make sure that they were far enough away from the drive shafts to prevent cavitation forward and loss of thrust in reverse. The stern on this boat is quite long and gradual. I used 1.6" diameter pieces cut from the prop template to provide the offset from the hull. Next I moved onto the water channeling, mimicking the layout Charley used with a few changes. Base layer is 1/4" balsa, surrounded by 1/2" balsa sticks to hold batteries, radio box, and CO2 bottle. I might have to downsize the CO2 bottle in the future to 5oz, but I'll try to make the 7oz work and go from there. The forward sections are hollow which I was hesitant to do. I layered 2 layers of fiberglass cloth over those sections, along with mat along all of the surfaces where balsa contacted the hull to prevent any gaps. Here is the hull after initial epoxy coats and fiberglassing the bow section. At the same time I reinforced some of the ribs with 1-2 layers on mat. I used microfiber filler on the outboard side of the balsa sticks. Around the prop shafts I decided to use filler to avoid excessive sanding. I also added some blocks on the back face of the gearbox to hopefully help hold everything together . Here is the boat in the morning after drying Now just a layer of cloth over the remaining sections. Used spray adhesive to help get it to stick in the corners. And now wet. The block in the middle is for the LiFe bricks which meet in the middle. I also added a layer of mat over the gearbox to further secure it to the hull (3rd or 4th layer of protection against movement) The final step before installing the deck will be the rudder post and servo mount. I will have to decide to either draw one up in CAD and then 3d print, or stick with wood/epoxy. Goal is to get the deck in by the end of next weekend. Thoughts/comments/suggestions are always welcomed!
I cut the prop shafts and soldered on the props yesterday. My plan to spend at least 15 minutes on the boat yesterday turned in to 1.5 hours, whoops. 1.6" Kort props from prop shop. Clearance seems to be OK From the stern Fortunately the California was willing to provide shore power and control services free of charge. The starboard prop wobbles a bit due to the poor job I did boring the hole out to 3/16"
I'm going to guess that it will hurt the start/stop of the ship as part of the thrust of each prop is stopped by the other prop. But we'll only know when you drive it next to a similar ship.
Well on my Espana (it has interleaved props) with the same general type of gearbox and I find that with the larger props it starts and stops very well. The position of them being closer makes the thrust of most of the water in the center of the rudder and helps turning. I try not to build a boat based on a guess.
Great Work!.. Keep up the Good Pics,,, orrrr maybe... Great Pics!.. Keep up the Good Work??????.... Whichever it is, Thanks for sharing the journey. Craig
