Ferrara Tanker

[Wombii]

Looks like a good plan. Looking forward to seeing how you'll fit it in the truck. From my tests I'd say there will be a surprisingly good flow from gravity alone for the dump chute, especially if the tank is tall.
I hope you'll have good tight plugs for the unused suction ports, as the pump will prefer to suck even a tiny bit of air instead of the tank water.
If you're only using gravity, you might be able to make a simple valve by bending a thin walled silicone tube with a servo. I accidentally bought a lot of silicone tubing that kinked badly when bending. It's used for fish tackle, apparently. If the dump chute is articulated or telescoping, you could maybe solve both with a single servo.

I don't know what type of pump you'll be using.
The real truck probably uses a centrifugal pump. Scale sized ones are commonly found as aquarium or garden fountain pumps. Single direction, very high volume but lower pressure at scale size. Needs to be below water level unless primed. (If you can fit a small one for the dump chute, it might do the job, but I don't know if it will leak air or water through when off).
I went with a diaphragm pump used in cheap high pressure washers or camper / boat kitchen sinks. Single direction, Large size, high pressure, good suction height, pulses the water flow a bit. Also very sensitive to a stray dog hair blocking the internal check valves, from experience.
Gear pumps are bidirectional and very high pressure, lower flow and good suction height. Sensitive to objects like dirt and sand. Scale sized ones are commonly found as r/c hydraulic pumps and r/c fuel fillers. I originally bought a nitro fuel filler pump, but wasn't completely happy with the flow rate. Two of them in parallel would have worked great though. Even though my gear pump had much lower flowrate when unrestricted, it could match the diaphragm pump when the nozzle was very restricted due to the extra pressure.
I think all types might be used as windscreen washer pumps?

[Tgrzes]

I have some ideas for the fittings. I have several of these brass faucet valves in the scrap bin that have 3/8” compression fittings. Most barbed fittings for tubing have a tapered pipe thread. The compression fittings have a regular 9/16-24 thread which should make it easier for me to modify the length for a more scaled look and fit rubber washers for a good seal. For the steamer blind caps, I’ll try soldering a plug to close the hole in the nut, then turn it round on the lathe and add some lugs. For the female hose fittings, I’ll solder a barb fitting. I also ordered a 9/16-24 die so I can either make the male ends from bar stock or cut the male thread off the valve body and solder a barb fitting to it. At least that’s the plan for now.


The last couple of weeks I spent a lot of time playing around with battery placement, motor/trans location, tilt cab hinge and new floor design all while keeping the cab interior somewhat to scale. I think I finally have a plan to move forward, so hopefully I can start posting some pics soon.

[Tgrzes]

Finally making a little bit of progress. The cab will be lowered, shifted forward and lengthened almost 3”, so I needed a new floor. After a lot of trial and error, I ended up using 1/8” ABS.






I’ll need four more seats, so I may try casting them using fast cast resin.


A coat of white paint for the pink shocks.


Finished up the hinges for the tilt cab.


I’ll eventually attach the cab to the floor with a few screws, so the entire assembly will tilt.