Shimakaze Cad Modeling

You should make a video of your process. Many of us would benefit from it; even if it's "raw", "messy", and "all over the place".

 

Ahh. Then a 3 minute video would be awesome!

 

How is this not NSFW?! Lookin' grrreat!!!

 

I think you may be working on details that your printer can't reproduce. But it's fun seeing your work.

I battled my Shimakaze exclusively in 2022 and I had a blast with it. I started with the same set of plans, but I tend to deliberately simplify parts. I'm looking for that "looks good" at 5' away, rather than scale accuracy.

 

I added 9.5mm in depth to the hull. The displacement of the ship ready to fight is 3.0 lbs.

I needed the extra depth for both displacement and for the components. My pump still didn't fit, so it penetrates the deck and hides under the superstructure.

 

Propulsion is two 2830 1100Kv brushless motors. Props are 3/4" x 25. The battery is a 7.4V 2 cell 1500 mAh LiPo. I'm running at 85% throttle to make 20 seconds/100'. I change the battery every 2 sorties and generally put 500 - 600 mAh into the battery to recharge it.

The rudder is controlled with an HS-82mg servo and ball chain drive.


The gun is a muzzle loaded, 15 round spurt gun. The pump is a printed resin body and impeller with a 380 size motor. From top to bottom the electronics are two brushless ESCs, Rx, brushed pump ESC.



From left to right the gun components are: fill indicator (on vertical wall), whisker valve and servo to fire gun, 2 cuin Clippard accumulator, QEV valve, 1/8" ID line to gun.

Also, the grey you see along the pump channel is lead ballast. I think there is around 8 oz of total ballast.

 

Is the “magazine” of the spurt gun, the section of copper tube between clear tube and threaded portion above deck?
Whats a whisker valve?
Fill indicator?

 

The short piece of copper tube is the magazine. It has a piece of 3/8 brass soldered on one end for the 10-32 fitting, and a barrel thread on the other end.

A whisker valve is a control valve that lets you bleed air from a circuit. It is small and takes very little pressure to activate, so a very small servo can be used.
https://www.clippard.com/part/MWV-1

The indicator just tells you if there is pressure in the system. When pressurized, a small pin pops up. Clippard doesn't make that model anymore, but here's something similar.
https://www.clippard.com/part/IND-3-GN

 

Ok. Thank you. So, the whisker value is piped to 2, 3-port manifolds: the 1st, 3-port mani is for the whisker valve itself and the indicator (correct?), the 2nd 3-port mani is fed from the 1st manifold (correct?)...where do the last 2 hoses connect? I'm not really understanding the whisker valve...how does it fire the cannon if there is only one hose to it??

 

It all comes down to how the quick exhaust valve (QEV) works. The accumulator fills through the QEV. As long as the pressure of the input and the accumulator are the same, nothing happens. When you reduce the pressure in the input line (by opening the whisker valve) of the QEV, the exhaust valve of the QEV opens and empties the accumulator. Here's Clippard's explanation: https://www.clippard.com/cms/wiki/how-does-quick-exhaust-valve-work

The check valve is required to keep pressure in the system when I disconnect the fill hose.

 

Do you have some sort of block-diagram-drawing program, or are you just that good at Paint? I am supremely jealous of your plumbing drawings.

 

Thanks for explanation. So, are all 15bbs expended in one burst or can it be reduced to 3-5bb bursts? Are you using CO2? Thx again.

 

It's all one burst. Once the QEV starts venting towards the cannon, the only way to reset it is to re-pressurize the system. Since it is supplied on shore via a quick disconnect, you effectively get one shot.

 

Oh ok. Thank you, better not miss, lol.

 

Yes, just one shot. When you hit it's great, when you miss it's a wasted sortie. I have a lot of fun with the psychological threat, lining up and not taking the slot, just to see them .
squirm.

I drew the diagram in powerpoint. I like powerpoint because once you attach the lines to handles on the boxes, you can move the boxes around and the lines adjust automatically.