• Howdy! we're looking for donations to finish custom knowledgebase software for this forum. Please see our Funding drive thread

Search results

Date Relevance Most replies

  1. A

    TIG torch for battery spot welding

    Is a vid available yet? What size dinse connector does it use?
  2. A

    bluetooth BMS?

    So I found the issue. It was a broken solder on that balance wire that was surrounded by heat shrink, so I couldn't tell the solder was broken, and that heat shrink SOMETIMES helped keep the connection. So when I tried to probe with the multi, the connection was fine, but as soon as I put the...
  3. A

    bluetooth BMS?

    Can anyone explain this? The app and the BMS itself is claiming that the 11th series battery is 0.1V and that the 10th is 4.9v. This is patently false because I checked each series with my multimeter and every battery is roughly 4v. And we also can tell that the 10th and 11th series voltage is...
  4. A

    improving standup scooter steering trail stability

    So I think I figured it out. I basically need to make the wheel axle move inwards/backwards, with respect to the steering axis. As it stands, the wheel axle is offset forward from the steering axis, and any forward offset from the steering axis decreases trail: As you can see from this...
  5. A

    improving standup scooter steering trail stability

    So I've custom modified a scooter similar to this: to go about 50mph. However, at those speeds the steering is extremely sensitive. I feel I need to have an extremely careful and firm grip so I don't twitch in the slightest otherwise I could crash. For stability at high speeds, I need more...
  6. A

    Electric Surf Board

    Florian, Can you post larger pictures of the boost internals? The small pics are kind of hard to see the details :D
  7. A

    Kepler Bottom Bracket Friction Drive For Sale (Finally)

    I didn't get a PM either?
  8. A

    Kepler Bottom Bracket Friction Drive For Sale (Finally)

    I would like at least 2 brackets. Let me know when they're available
  9. A

    bluetooth BMS?

    Did you wiring everything, including battery leads? I had the same problem when I just plugged in my balance wires, but didn't wire up my main battery leads.
  10. A

    Uber scoot 36v is 1000w

    Yeah, then you're going to have to upgrade the electronics - battery/controller/motor. You might be able to squeeze more out of the motor, so at least controller/battery. You will probably want to overvolt, to 48v, (at current gearing, will give you same torque but more top end) which means...
  11. A

    Looking for confirmation before ordering

    I think your math is correct, but there's no way you're going to hit 35mph on a 500w motor.
  12. A

    Uber scoot 36v is 1000w

    The only thing that doesn't require new electronics is to change out the sprockets. You basically change gearing, so you sacrifice acceleration to get more top end, and vice versa, like a bicycle.
  13. A

    openprop help

    That error looks like its because it couldn't open the output file for some reason. What is the full path to your project and project name? What version of matlab do you have? Are you using windows or linux? fusion360 support is going to take a while, if I even try to do it.
  14. A

    openprop help

    I've made a little bit of progress. I looked in the openprop source and found a parameter to output rhino3d and solidworks macros and I was able to hack the code so that those files are now created from the GUI. However, it looks like the macros are old and some of the commands are not...
  15. A

    openprop help

    Does anyone have experience using openprop? I have some questions. 1) What exactly does the ship speed parameter do in the GUI? There are no other parameters, like ship size or weight or drag coefficient or anything. Just speed, so how does only having the speed parameter provide any useful...
  16. A

    Electric Hydrofoil/E-Foil

    If the electronics get wet, that is clearly an engineering failure and I fully expect components to break. However, I wish to not die because of that failure :) AC supposedly kills "easier" because of its ability to fibrillate the heart, while DC "just" stops it. That doesn't mean DC can't...
  17. A

    Electric Hydrofoil/E-Foil

    I have some basic mechanical questions: How are you guys handling shock safety? Clearly the electronics need to be protected/waterproofed, but in the event the waterproofing fails and you have accidental contact of battery/live high voltage/amperage wires to the water? How are you sealing the...
  18. A

    Electric Hydrofoil/E-Foil

    Yes, I realize my error now. Its torque per amp that increases, but total torque remains the same. So with lower kv I can produce that same total torque with lower current (but at higher voltage), which tends to be easier in practice than trying to manage tons of current.
  19. A

    Electric Hydrofoil/E-Foil

    You have described what I had originally said - that lowering kv is the equivalent of mechanically gearing down - total power either watts or HP is voltage x current or RPM x torque. If you increase voltage, you decrease current or decrease voltage and increase current, given a fixed wattage of...
  20. A

    Electric Hydrofoil/E-Foil

    Not sure I understand/agree here. Why does lowering kv change the weight and size of a motor? Doesn't a lower kv simply increases torque at the cost of top end rpm, which is exactly what mechanical gearing does, but without the additional cost of the gearing itself, both in weight and...
  21. A

    Electric Hydrofoil/E-Foil

    What you're saying is simply to not use an underpowered motor and esc. I think that's a given. But you're not providing any information as to WHY some experienced cogging issues. I don't think "real" motors have to simply be large motors to handle high, sustained current. They can also use...
  22. A

    Electric Hydrofoil/E-Foil

    Just following this thread, as I'm interested in building one. I built an electric kick scooter that is loads of fun on land, and now its on to water :D A few questions. I see that there is discussion of using a gearbox - is that to keep RPM at target or mostly due to sync issues? Is sync...
  23. A

    bluetooth BMS?

    It goes into sleep if there is no Bluetooth activity for 10 seconds. The app polls the BMS constantly for real time data, so as long as the app is open, there is activity.
  24. A

    bluetooth BMS?

    Yes, the balance turn on voltage is when balance charging begins. It's slower, so typically it's set later, around 4v or so. My understanding is that the 200uA is used to detect a Bluetooth connection attempt, at which point it powers up fully. The Bluetooth module has a blue light that only...
  25. A

    bluetooth BMS?

    from aliexpress, link is on 1st post
Back
Top