R/C Naval Combat

Well, now it is time to kick off the Baden's build. Today was productive, I made the rudder servo mount and rudder post alignment critter (the mount does dual duty) and I made the belt box. anyways, I can't speak highly enough of the quality of Stephen's hulls (Strike Models). A nice thick (but not too thick) fiberglass layup.

First up are hull pictures, followed by pictures of the servo mount, and finally the pictures of the belt drive mount.

anyways, pictures!

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and here are a few images of how I am planning on laying her out at this point in time.

Well, there are two options.  Justin has one from Mtroniks that he is going to use in the Tirpitz, but it has not seen any real testing.  My ESC is a castle creations Mamba series , similar to this :

www.castlecreations.com/products/sidewinder_micro.html

that I had to make my own waterproof box for.  If the Mtroniks one works as advertised, particularly on current limiting, that will probably be the better ESC, however the mamba has worked for years for me (I even burned up the onboard BEC by overloading it and it still runs like a champ).  The big thing I like about the mamba's is with the interface cable, you can run the castle creations software on your computer and set just about anything you would want to set, which makes it easy to get going and set the brake & reverse as one desires it.

thanks Mikey!

Alright Folks , a question in need of opinions:

For the new one unit pump I am making based on the design of my half unit pump, I have two different options for motors.  Unfortunatly, due to the utter stupidity of the folks that build both classes of motors, the mounting patterns for the motors and the shaft sizes are different.  That means that the two motors are not interchangable.  If it was only the shaft, I could readily fabricate a suitable replacement that matched the sizes, but with both mount and shaft different, I really have to choose one to design and build the pump around, and hence the pump voltage of the ship...    both motors should happily run in the design range of the pump impeller of ~13000rpm if run on the right voltage source.  Both pumps have same material requirement.

I would like to hear opinions on either direction, as I can not see a truly overreaching reason to pick one over the other.  I currently lean towards the slower/smaller motor, but for no reason of any substance.   Even the extra tooling needed isn't a big deal as it is getting time to replace a bunch of my cutting tools anyways.

the picture shows the 1/2 unit pump on the left, the heli motor in the middle, and the plane motor to the right.  Basically, I have to

The specs and my notes are as follows:

Option A:  (call it the 6V ship power option, middle motor in the picture)

3500RPM/volt nominal  (free RPM of ~21000)

Idle current: 1.6A

Max Continuous Current 19A

Shaft size: 3mm, , 17mm spaced M3 mounting holes, 16mm spaced M2.5 holes

Bonuses:  6V primary power for entire ship,  12V suppliment still required for solenoids.  More powerful, higher speed allows overcoming losses by cranking up speed.  Could use onboard ESC's bec to power servos/reciever/ etc.

Negatives: Need additional tooling I don't have to fabricate impeller for 3mm shaft (probably 30$ worth of cutting tools, give or take).    Onboard esc's bec may (probably is) insufficient.

Option B:  (call it the 12V pump, 6V propulsion, right motor in the picture)

1360RPM/volt nominal  (free RPM of ~16000)

Idle current: 1.0A

Max Continuous Current 12A

Shaft size: 1/8 in, , 97mm spaced M3 mounting holes, 16mm spaced M3 mounting holes

Bonuses:  No tertiary 12V supply needed for cannons.  Tertiary 4.8V supply almost certainly needed for servo's & RX.  Motor top end closer to design point of pump, slower top end speed, not as much overage available on design point of pump.  I have basically all the tooling needed to fabricate this pump now.

Negatives: Less overage available as far as speed is concerned.  No BEC as a viable option, as the bec's are typically linear voltage converters, 12V to 5V tends to get awfully hot if not carefully cooled and can let out the magic smoke.  

I like the smaller slower less voltage motor. In a Baden, it would be nice to be able to keep it all 6 volts. There isn't a lot of room for extra power systems and more volts do equal more power drain (usually) and heat. A pump would be running a lot.

Greg, not to hijack the thread (great by the way), I just got a mini mill (Micro Mark) and am looking to get cuttters, setup stuff. Any advice (I know about little machine shop), was looking at their basic setup for 300.00

Thanks, Lou

A friend of mine made these on his plasma table as a test.  the table is new and still needs a little tweaking so the holes are circular, but I can fix that on the mill rather readily, I suspect.