First foray into Twins

[RaceMechaniX]

Hi Glenn, no it's not ready yet. Waiting for the weather to warm up so I can clear coat. I also still need to build front and rear sponsons and set-up the driveline.

-Tyler

 

[Christian Lucas]

Hi Tyler,

you know whatˋs waiting for you . Crazy smooth run rigger like this smaller twin, https://youtu.be/mxRWXDSbB5E .

And the very little twin from Patrik , https://youtu.be/FRVeXgEJBNM, but this is moore a dragboat reaching topspeed of 108 mph.

Happy Amps Christian

 

[RaceMechaniX]

Hello Christian,

I am excited to get this finished and out racing. It will not make it Munich though, takes up too much space in the golf bag.

Did you ever test your direct drive big diameter prop rigger? The one with the OS outrunner?

-Tyler

 

[Christian Lucas]

Hi Tyler,

have run to test the propeller on a smaler monohull ,just hang on like a outbord . Need a tube like a propshaft to get a thin gap for smooth waterstream than it workes . i have not managed it to run the rigger ,to less time and i want to wait for the samler outrunnermotor from Hans Lehner . But Hans is currently to bussy with the big outrunners so he dosnˋt force the smal to come to the market. The smal one will be a powerhouse ,that show the results of the prototypes they run in helicopter.

Hope to see you in Munich.

Happy Amps Christian

 

[Gilbert Pun]

Yeah, one M400 or M410 should provide enough cooling when the boat is stopped or running slow. Plumb it inline to use the pickup pressure to increase flow at higher speeds.

What remote switch you use to turn on the pump ?

 

[Steve Seebold]

Hey Tyler, I have made running gear for Marc in the past. I am still making gear similar to his but Ive added s couple of cosmetic changes.

Maybe if you decide to do another one, we can talk about hardware for it.

Remember I do make one offs as well.

 

[RaceMechaniX]

@Gilbert, the pump runs off the normal receiver power so as long as I have a typical receiver switch everything works fine. In boats where I am using BEC power from the ESC, I usually just let the pump run while taping up. Not ideal since the pump runs dry, but they are pretty robust little pumps and I have not had a problem yet.

Steve, Thanks for the offer.

Tyler

 

[Gilbert Pun]

@Gilbert, the pump runs off the normal receiver power so as long as I have a typical receiver switch everything works fine. In boats where I am using BEC power from the ESC, I usually just let the pump run while taping up. Not ideal since the pump runs dry, but they are pretty robust little pumps and I have not had a problem yet.

Steve, Thanks for the offer.

Tyler

Lucky you, I've got 4 M410s ordered after talking with you, very unfortunate 3 of them got dead after the initial test run even with water primed in it, I've sent them back for repairs. While using separate battery to run the pump, I am looking at some possible remote switch after putting the boat on the water, looking at to use small brushed BEC if at all possible.

Most of the time the temperature here is close to 100degrees F , I run my battery with water cool as well.

Gilbert

 

[RaceMechaniX]

What voltage pumps did you get and did you run a voltage regulator?

 

[Gilbert Pun]

What voltage pumps did you get and did you run a voltage regulator?

I've got the 12V pumps and run on 3S Lipo.

 

[GraysonTaylor]

Pololu sells nice relays that plug into your receiver. 10 amp rating. That way you can turn your pump on with a free channel. I got a couple of them to make an rc rocket ignition system.

 

[RaceMechaniX]

Gilbert, they should be OK. I have about six of the pumps and no issues. I have started to use the Pololu regulators to make sure I am not applying too much voltage.

The mini relay would also be a nice feature. On the larger pumps I use an external brushless motor controller and control the pump speed like it was a third channel from the receiver.

@Grayson, do you have a link to the relay?

 

[Gilbert Pun]

Gilbert, they should be OK. I have about six of the pumps and no issues. I have started to use the Pololu regulators to make sure I am not applying too much voltage.

The mini relay would also be a nice feature. On the larger pumps I use an external brushless motor controller and control the pump speed like it was a third channel from the receiver.

@Grayson, do you have a link to the relay?

Tyler

Thank you very much for the advice, I am using brushed ESCs and limiting the output through transmitter endpoint to control on the fourth channel for limiting voltage avoiding its going over.

Other remote switch I have been looking into and tried are mostly for lights and small current control.

 

[RaceMechaniX]

Ah that's your problem. You should not be using a brushed ESC to limit the voltage to the M410 since it has a brushless motor controller already. Just get a simple voltage regulator and switch. When you use the brushed ESC controller it is chopping the voltage to the M410, but this hurts the electronics in the M410.

Here is a 12V step down regulator: https://www.getfpv.com/12v-step-down-voltage-regulator.html

Here is the Pololu relay: https://www.robotshop.com/en/pololu-rc-switch-relay.html?gclid=Cj0KCQiA2NXTBRDoARIsAJRIvLyfwnwYZvodm7UEtpnqf7CgQnxe4pAYa0J8N-0Aqg3sWkoJmvMMFv4aApeLEALw_wcB

or this one from Turnigy: https://hobbyking.com/en_us/turnigy-tx-controlled-relay-switch.html?___store=en_us

 

[Gilbert Pun]

Ah that's your problem. You should not be using a brushed ESC to limit the voltage to the M410 since it has a brushless motor controller already. Just get a simple voltage regulator and switch. When you use the brushed ESC controller it is chopping the voltage to the M410, but this hurts the electronics in the M410.

Here is a 12V step down regulator: https://www.getfpv.com/12v-step-down-voltage-regulator.html

Here is the Pololu relay: https://www.robotshop.com/en/pololu-rc-switch-relay.html?gclid=Cj0KCQiA2NXTBRDoARIsAJRIvLyfwnwYZvodm7UEtpnqf7CgQnxe4pAYa0J8N-0Aqg3sWkoJmvMMFv4aApeLEALw_wcB

or this one from Turnigy: https://hobbyking.com/en_us/turnigy-tx-controlled-relay-switch.html?___store=en_us

Thanks, Tyler, too bad the Turnigy unit is out of stock.

A servo control of microswitch of inboard starter for on/off is too heavy!

FYI, I have been using the brushed ESC to control the bigger/heavier brushed motor MHZ water pumps to switch on/off of water cannon, rocket firing and water pumps in bigger scale boats with no problems, but they are very heavy set ups.

Perhaps, I would look into the small brushless ESC on the next trial.

 

[RaceMechaniX]

Hello Gilbert,

Perhaps I was not clear. The M410 already has a brushless controller inside the pump. Just supply it with 12V, do not use anything but an on/off type control. A brushed ESC chops the voltage which damages the internal speed control inside the pump.

Those external ESC's probably worked fine on the MHZ water pumps because those are brushed motors.

TCS do make pumps that require an external brushless controllers if you want to go that route.

-Tyler

 

[Gilbert Pun]

Hi Tyler,

Right you are and thank you very much for the valuable advice, I am still looking for the suitable Remote control on/off switch, or a small brushless ESC, for that matter.

And awaiting for the made good pumps to come back, they are a long way away from me.

Gilbert

 

[RaceMechaniX]

https://www.towerhobbies.com/cgi-bin/wti0001p?&I=LXDVBT&P=7

https://www.amainhobbies.com/futaba-cps1-channel-power-switch-futcps-1/p646069

 

[charles siler]

Any updates on the build ?

 

[RaceMechaniX]

Waiting for the weather to improve so I can paint.