TFL Patron Saint "Outerlimits" "Lucky Oct" 1330mm brushless buid

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  • Old School
    Senior Member
    • Aug 2017
    • 686

    #31
    Mechanically the boat is now complete. I am awaiting a 63mm three-blade propellor. I had intended commencing with a 60mm 3-blade, but due the lower rpm of running 8s, I skipped the testing phase of running with the smaller prop. Still to do are the electrical connections. The Hifei 300 amp ESC will be mounted just forward of the motor so will connect directly to the motor. The Hifei battery connector/capacitor board still needs to be soldered to the ESC inputs. As there will be two 4s batteries in series each side then I need to solder the electrical connection to join the batteries to the capacitor connector board in parallel as the Hifei ESC has four input wires. I will fit an additional four capacitors each side which hopefully should be sufficient.

    As regards one steering control cable being nearly 2 cm shorter than the other, I needed to mount the servo horns slightly off "centre" to allow the shorter cable to protrude a little further through the cable clamp on the port side servo horn. Aesthetically the artistic side of my brain did not like this as it makes the servos appear not centred, however, with the deck lid on this will not be seen. On the longer starboard side cable I was able to fit a secondary clamp so should disaster strike with the port side cable then I should still have steering control to the right to "get me home".

    I can finally see light at the end of the tunnel on this build with another possible build in the future. I like to build as it keeps my brain stimulated and leave the testing to my son.

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    • Old School
      Senior Member
      • Aug 2017
      • 686

      #32
      Pushing on with the build. The ESC mount plate is now installed as well as the small mount for the ESC on/off switch mounted to the midship bulkhead. The position of the ESC allows direct connection to the motor inputs. The Hifei battery connector/capacitor board will be fitted to the aft face of the bulkhead above the ESC. By necessity the ESC will be mounted upside down as all the terminals are on the lower face of the ESC body. Aesthetically I should pigment the resin glue black to tone in.

      Edit: ESC and motor now wired up. I am awaiting the resin to cure on the ESC mount before I am able to fit the ESC, which hopefully should be tomorrow. This will leave just wiring up the four batteries and connecting the cooling outlet hoses. There is light at the end of the tunnel. Still awaiting the prop and additional capacitor packs.
      Attached Files
      Last edited by Old School; 06-04-2021, 01:40 AM. Reason: Additional info

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      • Old School
        Senior Member
        • Aug 2017
        • 686

        #33
        This morning I soldered up the battery connections. I needed a series set up each side and then the connection to the capacitor board. The current set up is to test operation. I am awaiting two Hifei capacitor packs to fit one each side. I have posted a question on the ESC talk forum as to whether I should get a cell count signal when powering up the Hifei Swordfish Pro 300 amp ESC. The unit seems to run just fine on test.

        Edit: with the batteries in the shown position I estimate a CoG of 28%. Moving the batteries further to the rear gives barely a marginal decrease but the batteries would interfere with the steering cable support tubes.
        Attached Files

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        • Old School
          Senior Member
          • Aug 2017
          • 686

          #34
          Getting closer to the finishing line (or is that the start line). Still to complete are the 63mm 3-bladed prop and a capacitor bank for each side of the battery supply. Due a warning on the ESC case that a short circuit will damage the ESC if the positive supply accidentally touches the case, I have constructed a cover from G10 fibreglass plate that will hopefully prevent any accidents occurring. The plate will cover the exposed section of the ESC that projects forward of the midship bulkhead. After the resin has cured I will attach the cover to the ESC using sealant.

          edit: Due the directed thrust from the Arneson drive I am assuming that turn fins are not necessary. I do wonder though that the aft end of the boat may spin out in a tight turn.
          Attached Files
          Last edited by Old School; 06-05-2021, 09:31 PM. Reason: Additional info

          Comment

          • Jesse J
            scale FE racer
            • Aug 2008
            • 7116

            #35
            I would be ready to install the turn fins... if not install and have the ability to adjust. F you want that boat to turn medium to sharp, then turn fins will be needed IMO.
            "Look good doin' it"
            See the fleet

            Comment

            • Old School
              Senior Member
              • Aug 2017
              • 686

              #36
              Many thanks. I will source a large set just in case they are needed.

              Edit: I calculate that I will need fins approximately 90 mm long.

              Comment

              • Old School
                Senior Member
                • Aug 2017
                • 686

                #37
                I revisited the wiring to the ESC capacitor board. My original set up was to ensure the system worked on test. This afternoon I modified the wiring each side leaving just the connectors to wire the two batteries in series and then the 8mm bullets to the capacitor board. This removed one surplus connection each side plus around 30cm of wire in each loom. A Hifei capacitor pack will be soldered each side just forward of the midship bulkhead where the wires emerge.
                Attached Files

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                • Old School
                  Senior Member
                  • Aug 2017
                  • 686

                  #38
                  Minor progress. The G10 fibreglass shield is fitted to the exposed portion of the ESC as any accidental contact with a positive terminal will let the expensive magic smoke out of the ESC. The small carbon fibre plates either side of the longitudinal rails are to mount the Hifei capacitor boards, one each side.
                  Attached Files

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                  • Old School
                    Senior Member
                    • Aug 2017
                    • 686

                    #39
                    Probably overkill but due my concerns of shorting out the ESC negatively charged case with the positive battery leads, I decided to add two dummy 8mm male fittings to the rails so that when connecting the series batteries each side, the positive lead will be safely out of the way until needed.
                    Attached Files

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                    • nocebo
                      Member
                      • Jun 2020
                      • 79

                      #40
                      Originally posted by Old School
                      Probably overkill but due my concerns of shorting out the ESC negatively charged case with the positive battery leads, I decided to add two dummy 8mm male fittings to the rails so that when connecting the series batteries each side, the positive lead will be safely out of the way until needed.
                      Super neat solution

                      Comment

                      • Old School
                        Senior Member
                        • Aug 2017
                        • 686

                        #41
                        It came as a spur of the moment thought. I simply drilled an appropriate hole in the rail and then using the existing holes in the shouldered section of the fitting I inserted a 2mm rod vertically down through the rail holding the fitting captive. A small length of appropriately sized brass tube made up the difference between the diameter of the 2mm rod and the inside diameter of the hole in the male fitting.

                        Comment

                        • nocebo
                          Member
                          • Jun 2020
                          • 79

                          #42
                          Originally posted by Old School
                          It came as a spur of the moment thought. I simply drilled an appropriate hole in the rail and then using the existing holes in the shouldered section of the fitting I inserted a 2mm rod vertically down through the rail holding the fitting captive. A small length of appropriately sized brass tube made up the difference between the diameter of the 2mm rod and the inside diameter of the hole in the male fitting.
                          I hope you dont mind me stealing the idea for my build! Seems like a lightweight but easy way of keeping wires from flopping around and possibly shorting while things are not plugged in.

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                          • Old School
                            Senior Member
                            • Aug 2017
                            • 686

                            #43
                            No problem, we post to perhaps give others ideas.

                            Comment

                            • Old School
                              Senior Member
                              • Aug 2017
                              • 686

                              #44
                              Refer this thread regarding a cap bank self destructing.

                              https://forums.offshoreelectrics.com...d-installation

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