Stealthwake 23 - Centered Battery Poistioning

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  • wake_n_bake
    Junior Member
    • Dec 2020
    • 10

    #1

    Stealthwake 23 - Centered Battery Poistioning

    Hello. Forgive me if these are dumb questions but I am new to the rc world and I'm having a blast learning about and upgrading (and breaking) the Stealthwake but wanted to ask about something that's been driving me crazy... the battery location. With the positioning as it comes from the factory, the boat sits off-balance in the water, (leaning to the left) and this impacts performance especially when turning or jumping.
    I cut small slits in the canopy to suspend the battery nice and tight with velcro, exactly centered, which made the boat sit perfectly level in the water. I don't jump it often (right now I'm just experimenting with fpv cameras and smoother rides) but was wondering why nobody else has done this. Am I setting myself up for disaster with the battery being up higher than it was? Was the original location of the battery critical to functionality? Will I flip my boat lol?
    Right now the ride seems smooth enough to me but I'm pretty sure with a 3s brushless upgrade and some jumps into the wind, I the boat might be less stable than it was.

    Thank you for any insight / advice.
    Attached Files
    Last edited by wake_n_bake; 04-20-2021, 06:12 PM.
  • fweasel
    master of some
    • Jul 2016
    • 4286

    #2
    You've raised your center of gravity significantly by positioning the battery under the canopy like that. Not sure of that boat is fast enough in the stock configuration for that to matter, but it will certainly be less stable in rough water. Lowering the weight in a hull makes it more stable.

    Weight (batteries, motor, electronics) in a hull is usually situated to attain a reasonable center of gravity fore and aft, approximately 30% of the hull length when measured from the transom of the hull. Because the motor and drive line must be centered in the hull, there's not always room to keep the battery weight centered left to right as well. This is one of the reasons a single battery setup usually has the battery on the left side. When the prop spins left (CCW) it wants to make the hull roll to the right. Since you've got to pick one side or the other to place a single battery, placing it on the left side is preferred to help counteract the roll induced by the prop. Yes, the creates a static weight bias so the boat tends to lean to the left a little when not moving or at slower speeds. As you move up in boat performance, you'll find those hulls use centered batteries, or dual battery setups split evenly on each side. Not much real estate to work with in the smaller entry level hulls.
    Vac-U-Tug Jr (13mph)

    Comment

    • wake_n_bake
      Junior Member
      • Dec 2020
      • 10

      #3
      Gotcha, thanks for the explanation. I hadn't thought of the prop spinning ccw / battery on the left side relationship. Maybe changing the weight distribution just doesn't impact stability all that much for me to notice because it's still the stock config but I will surely be cautious and maybe put the battery back when I upgrade the motor because I don't want to flip her over out in the bay. Thanks!

      Comment

      • Panchothedog
        Senior Member
        • Oct 2015
        • 173

        #4
        You said that you cut small slits in the canopy ( it's called a hatch ) if they go all the way through you are setting yourself up for major water intrusion and sinking when the boat gets upside down,and it will. Please seal them up before you run again. Keeping the inside of the hill dry is of utmost
        importance

        Comment

        • wake_n_bake
          Junior Member
          • Dec 2020
          • 10

          #5
          Originally posted by Panchothedog
          You said that you cut small slits in the canopy ( it's called a hatch ) if they go all the way through you are setting yourself up for major water intrusion and sinking when the boat gets upside down,and it will. Please seal them up before you run again. Keeping the inside of the hill dry is of utmost
          importance
          Thanks Panchothdog. I will definitely keep that in mind. I have a second hatch for everyday use, which hasn't been modified at all. The hatch I cut the slits into is exclusively for days when I'm out experimenting with fpv cameras. The slits are just wide enough for velcro straps and my make shift grommets actually do a solid job of keeping everything dry (tested in the bath tub) but I only take that hatch out when the water is like glass and I'm trying to capture nice smooth video.

          Comment

          • NativePaul
            Greased Weasel
            • Feb 2008
            • 2760

            #6
            I dont know this particular boat but as well as losing g the torque compensation raising the CoG, and potential water i trusion, if the boat was self-righting before you will have lost that feature.
            Paul Upton-Taylor, Greased Weasel Racing.

            Comment

            • fweasel
              master of some
              • Jul 2016
              • 4286

              #7
              Originally posted by NativePaul
              I dont know this particular boat but as well as losing g the torque compensation raising the CoG, and potential water i trusion, if the boat was self-righting before you will have lost that feature.
              No, this hull was not self righting.
              Vac-U-Tug Jr (13mph)

              Comment

              • wake_n_bake
                Junior Member
                • Dec 2020
                • 10

                #8
                Correct, no self-right function. I have officially been scared away from using the cam-hatch now, even in "safe" conditions :) My camera attachments finally arrived anyway.

                Comment

                • sciesielka
                  Member
                  • Aug 2019
                  • 90

                  #9
                  Originally posted by wake_n_bake
                  With a 3s brushless upgrade and some jumps into the wind, I am concerned the boat might be less stable than it was.
                  My son has the Stealthwake and we've been upgrading it over the past year. We went with a 3660 2600KV and usually run it on 2S (19,240 RPM on 2S and 28,860 RPM on 3S which is good for 'playing with' and/or smaller ponds/lakes). Even when everything else was stock, we never flipped or rolled it, even running in high winds (20+mph with higher gusts) and "rough seas." The only time we ran that motor on 3S, it blew over and peeled the hatch off. Thankfully the pool noodle that was factory installed kept the bow up and we miraculously were able to drive it back to shore 80% submerged! That was with the solid shaft still installed. We've since installed a flex shaft and strut recently but the local ponds are all frozen over so we never got to test a 3S in 2020

                  My recommendation, if you upgrade to brushless, is to install a longer blade metal rudder as soon as possible. The improvement in handling is dramatic! Best next upgrade after brushless! We have videos and info on the upgrade process including running videos available at: http://myplace.frontier.com/~sv_design/s_wake.html
                  Last edited by sciesielka; 12-11-2020, 03:27 PM.
                  Info and pictures about our Invincible Razor build, Lindberg PT Boats; Racing Runabout; Pro Boat Stealthwake and more! Plus videos of our boats including upgrades, repairs, etc.

                  Comment

                  • sciesielka
                    Member
                    • Aug 2019
                    • 90

                    #10
                    Originally posted by wake_n_bake
                    Correct, no self-right function. I have officially been scared away from using the cam-hatch now, even in "safe" conditions :) My camera attachments finally arrived anyway.
                    We have run with a gopro style camera mounted on the hull with the brushless setup (stock solid-shaft driveline) and the boat never flipped but on 2S only. And I've seen videos online with FPV and other gopro style cameras.

                    And make sure you have a recovery boat (real or R/C) or a fishing pole with a ball to recover it every time you go out just in case. We've only had to recover the Stealthwake 2 times in probably 70 runs: 1) battery on Tx died; 2) our Shockwave flipped over right in front of the Stealthwake and it launched and landed upside down. We don't count the blow over with the 3S since it filled with water, rolled over and drove back under its own power (would have preferred to have to recover it and have the hatch stay on)
                    Info and pictures about our Invincible Razor build, Lindberg PT Boats; Racing Runabout; Pro Boat Stealthwake and more! Plus videos of our boats including upgrades, repairs, etc.

                    Comment

                    • wake_n_bake
                      Junior Member
                      • Dec 2020
                      • 10

                      #11
                      Originally posted by sciesielka
                      We have run with a gopro style camera mounted on the hull with the brushless setup (stock solid-shaft driveline) and the boat never flipped but on 2S only. And I've seen videos online with FPV and other gopro style cameras.

                      And make sure you have a recovery boat (real or R/C) or a fishing pole with a ball to recover it every time you go out just in case. We've only had to recover the Stealthwake 2 times in probably 70 runs: 1) battery on Tx died; 2) our Shockwave flipped over right in front of the Stealthwake and it launched and landed upside down. We don't count the blow over with the 3S since it filled with water, rolled over and drove back under its own power (would have preferred to have to recover it and have the hatch stay on)
                      Yes indeed. I have a little fishing boat that I am slowly converting into an all out camera boat with 4k / fpv cameras mounted on top / under water but it seconds as my recovery boat. I'm hoping to eventually set it up in a way that allows for me to hook onto a cleat or something mounted onto the bow of the stealthwake and really tow it back as opposed to the fishing line / circling scenario but it works this for now.

                      And thanks, I have successfully recorded some video with a top mounted camera but only using the NiMH battery that came with it. You can see that here - https://youtu.be/kHi0A8aDd84. I'm going to get a camera on the rear as well soon.

                      I'm reeeeally itching to get the upgrades in there and see what it can do.

                      Comment

                      • wake_n_bake
                        Junior Member
                        • Dec 2020
                        • 10

                        #12
                        Originally posted by sciesielka
                        My son has the Stealthwake and we've been upgrading it over the past year. We went with a 3660 2600KV and usually run it on 2S (19,240 RPM on 2S and 28,860 RPM on 3S which is good for 'playing with' and/or smaller ponds/lakes). Even when everything else was stock, we never flipped or rolled it, even running in high winds (20+mph with higher gusts) and "rough seas." The only time we ran that motor on 3S, it blew over and peeled the hatch off. Thankfully the pool noodle that was factory installed kept the bow up and we miraculously were able to drive it back to shore 80% submerged! That was with the solid shaft still installed. We've since installed a flex shaft and strut recently but the local ponds are all frozen over so we never got to test a 3S in 2020

                        My recommendation, if you upgrade to brushless, is to install a longer blade metal rudder as soon as possible. The improvement in handling is dramatic! Best next upgrade after brushless! We have videos and info on the upgrade process including running videos available at: http://myplace.frontier.com/~sv_design/s_wake.html
                        Thank you for these words of wisdom. Wow I'm amazed and happy to hear you were able to tow it back in that condition. I have a small 3s sitting on my table begging to be put in "just for a quick second" but I'm pretty sure that would result in a bad day so I'm going to resist.

                        That link brings me to what started this all for me! I currently have that rudder assembly and the angled trim tabs on order. I am also probably going to pop in a DYNM3831 and a DYNM3876 assuming they all play nice together.

                        Comment

                        • sciesielka
                          Member
                          • Aug 2019
                          • 90

                          #13
                          Originally posted by wake_n_bake
                          I'm hoping to eventually set it up in a way that allows for me to hook onto a cleat or something mounted onto the bow of the stealthwake and really tow it back
                          Get your tow hook here from OSE. https://www.offshoreelectrics.com/pr...prod=ose-83002
                          We have the "small" on the Stealthwake and Shockwave.

                          And great video!
                          Info and pictures about our Invincible Razor build, Lindberg PT Boats; Racing Runabout; Pro Boat Stealthwake and more! Plus videos of our boats including upgrades, repairs, etc.

                          Comment

                          • wake_n_bake
                            Junior Member
                            • Dec 2020
                            • 10

                            #14
                            Thanks. That does look cool. I might need something bigger or with an complete loop though.

                            Comment

                            • sciesielka
                              Member
                              • Aug 2019
                              • 90

                              #15
                              Originally posted by wake_n_bake
                              I am also probably going to pop in a DYNM3831 and a DYNM3876 assuming they all play nice together.
                              That ESC and motor should work fine together. The motor and ESC connectors are both 5.5mm bullets so you won't have to solder on different ones. And the ESC says it has an EC5 connector, so you may have to convert your batteries as they are EC3s. Otherwise you can make or buy an adapter. In your case, with an EC5 on the ESC and if you keep the EC3s on the batteries, you can buy the EFLAEC510, EC3 Device / EC5 Battery with 1.5" Wire, 12 AWG: "This adapter adapts a battery with an EC3 connector to a device with an EC5 connector"

                              My 3-cell LiPos have EC5 connectors for the Shockwave but all of our NiMh and 2-cell LiPos have EC3s because we use those in the R/C cars and other boats. So for the Stealthwake, which has an EC3 on the ESC, I just made an adapter for when we try a 3-Cell with the EC5.
                              Info and pictures about our Invincible Razor build, Lindberg PT Boats; Racing Runabout; Pro Boat Stealthwake and more! Plus videos of our boats including upgrades, repairs, etc.

                              Comment

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