Victor III

[bwi 971]

Inserts in place, motor attached.



Servo link bushing glued in place shaft seal fitted.



Servo rack attached to endcap (3 servo's)





test fitting ballast tank and aft compartment


ESC for propulsion and pump will also live in the aft compartment, space is available.





Ballast tank layout.



Grtz,
Bart

[bwi 971]

I had a new insight regarding 3D resin.

The pump was left with water inside, and a few days later, I tried to turn it, but it was seized. After opening it up, I noticed the gears had become soft and were squeezable. I directly linked this to a message on a Dutch forum where a fellow modeler had experienced the same issue with water-washable resin on a 3D printed shroud. Since I don't use that kind of resin, I thought I would be okay. The parts were unpainted.

I did some research on the web and found out that depending on the brand and type, some printed resins can expand significantly and become quite soft when submerged. The good thing is that they will return to their hard state once they dry out.

I did not find the critical submersion time before the effect takes place, but my pump is a critical part and will contain water for a longer period of time. I'm reprinting the pump with a different resin and will run some more tests.

Meanwhile, I traced all embedded lines to make them more pronounced and working on the fwd dive planes.
I was very happy that I managed to position on of the frames right on top of the rods of the bow planes, so I needed to partly crop the frame.

























Grtz,
Bart

[Subculture]

Never had much luck with geared pumps using plastic gears. Sadly not a lot of choice for smaller metal geared pumps now. Kavan make a nice geared pump, but it's fairly large, could fit a smaller motor to the pump head of course.

Also seen pumps from China which are pitched for use with hydraulics (oil) so not sure if the parts will be compatible with water, but small and brushless. e.g. https://tinyurl.com/5yx35pm5

[bwi 971]

Various Progress

I reprinted all parts with the new resin as it withstands water.




Servo Linkages
I don't like the Z bends to connect the rods to the servo horns. Especially in combination with brass horns, I find it a PITA. I opted for a 90° sharp bend by grinding a corner out of the rod. After bending, I applied some soft solder to give it back some strength. I designed a snap-on retainer to prevent the rod from working its way out of the connection. To prevent the rod from bending when the servo horn turns, I provided a hinged setup. The O-rings for the link bulkhead penetration came in. The bulkhead penetrations were fixed in place with blue Loctite sealant, which was also used to seal the holding bolts of the motor.

















The oilite bushings for the prop shaft were pressed in place, and the collar of the outer bushing was turned down to fit into the provided recess.







All the new ballast tank appendages were glued in place using the Loctite blue sealant.









The forward endcap was prepared with a connection for the pressure sensor and a recess for the WT toggle switch.









Grtz,
Bart