Discussion in 'Midwest Naval Combat Club' started by rcengr, Apr 15, 2020.
What pump is that? the 90 degree outlet is different from most small water fountain pumps I've seen.
I don't remember where I got it. I've also got one with a side discharge, those are more common. You can get one with the vertical outlet here: https://www.adafruit.com/product/4547
Longevity of the pump is a concern, especially since I'm running it at 6.6V and it may be only rated for 3V.
was that little Golo??
No Nikki. That's the Diver. New design he's been working on for a while in this thread. Last two pages or so.........
Its looks like her.
On post #16 there is a picture of both ships together.
So the pump has already failed. The first time I hooked it up the speed was very erratic. I put a watt meter on it and it had very high no load current. Since I'm not one to give up without a little trouble shooting, I filled the ship with water and ran the pump for a while. It continued to be erratic and use a lot of current. So I changed to my side discharge pump. It ran reliably, drawing o.4 amps under load and around 0.15 Amps unloaded. The pumping was 0.43 gallons per minute, down from the 0.6 gallons measured with a less restrictive outlet.
I did an autopsy on the pump to see what went wrong. It looks like there was an excess of grease on the brushes that caused poor commutation. A heck of a failure for a pump advertised as "brushless".
Are the brushes at least carbon? No - just copper
Is there a seal on the motor shaft? No - it relies on the bearing to keep water out of the motor.
Does it have a volute? I'm going to give it this one. It is really just a circular collector, but at least the rotor is off center.
For a small pump, I really like ones like this. It is brushless (impeller on a shaft housing permanent magnets, Stator windings potted in surrounding case). Runs really efficiently at around 0.1A no load ~.5A full load. I've run it effectively between 7V-12V. Requires modification by cutting off the bottom hose barb and drilling a pilot hole next to the outlet barb.
Will that work in the ships??
I've been working on the Tugster as my number one priority. It would not do to not have a rescue boat for this weekend.
I've fixed a loose rudder, installed a new ball chain drive for the rudder, and wired new ESCs. All the bling is finished too. The recovery scoop is wired up, the siren works, and the lights are operational.
There is a significant amount of electronics for this boat. From the left: The switch to control the lights along with a voltage booster to generate the 12V for the light. The speaker. The sound card with 2 watt amplifier, switch, and sound player. The ESC for the recovery scoop motor, and the limit switch board.
And it all works!
Tugster is the only ship to sunk a combat ship
I got the Tugster and the USS Diver on the water this weekend.
The new ESCs and updated programing improved the drive ability of Tugster. The recovery scoop also worked. It was tricky to use because if you backed up too fast and gave it a little forward throttle to slow down, it prop washed the object to be recovered farther away. I'm going to program a mode where the differential thrust is done only by reverse thrust instead of both forward and reverse.
The Diver made some test runs but I didn't get the pump hooked up so it did not participate in any battles. It is very maneuverable. It is also pretty stable, it is pretty windy in the video and it still handled it well.