R/c Warship Combat Thread

[CT96]

So, the topic came up in the FFZ Raspberry Pi thread about my R/C Warships hobby (specifically, using a Raspberry Pi to control the ship), so rather than pollute that thread, I'm creating one here by request.

 

Sometime in the late 90s I got into R/C Warship Combat, specifically Big Gun Model Warship Combat (as opposed to the "Fast Gun Model Warship Combat" at the same scale but with very different rules).

 

Basic premise is this: We build and fight 1/144th scale model warships of any ship at least laid down between 1 Jan 1905 and 1 Jan 1946. This allows us to build Predreadnoughts, Dreadnoughts, SuperDreadnoughts, the epic WWII Battlewagons (Yamato, Iowa, H39) and any/everything else as far down as we can possibly build (PT boats while legal under the rules are basically unbuildable, and Submarines are extraordinarily expensive and largely ineffective). The focus is the big battleships. Guns are CO2 powered (no pyrotechnics) and fire anything between BBs up to 1/4" ball bearings - depending upon the caliber of the gun carried on the ship. The Balsa skin is anywhere from 1/16" up to 1/8" depending upon the armor of the original ship (unarmored is 1/16"). Pumping capacity was based on displacement, etc.

 

The group I was with was then known as the Blacksburg Battle Group, based out of Blacksburg, Virginia. Mostly Engineering students, but the co-founder of the club with me was actually a Comp Sci guy. We did have a few History majors, but the focus was mostly technical. The Co-Founder had purchased a used German Battleship Gneisenau https://en.wikipedia.org/wiki/German_battleship_Gneisenauwhich I helped him sail, and got me hooked. My roomate and I decided to go in together on an Iowa class (Specifically USS Missouri) which I still have in my garage (though it has not sailed in years). Meanwhile the co-founder scratch-built his HMS Lion. As the club grew, and some of us moved away from Blacksburg in our post-college years, we became the Mid Atlantic Battle Group. In recent years, my co-founder has had a couple of kids under the age of 4, and I've been too busy, and the group has largely gone idle. Now that I own my own place, and am not spending vast lengths of time sitting on public transit to/from work I am probably going to try to get things moving again.

 

nabqrules was one of my roommates late in college, and a little after, and he built a Bismarck, and was actually active for a little bit longer after I went into the Army in 2003. We both have some pics to share, and will be happy to answer questions, etc. further along.

 

They really do shoot each other:

 

They really do sink:

 

But we patch and go for revenge:

 

My CV6 CAD Project http://www.tank-net.com/forums/index.php?showtopic=39829is, ultimately, intended to come up with a proper model that will work within these rules and be able to sail with this club.

 

More pictures and discussion to follow.

[CT96]

My USS Missouri, built c. 1997 is 6'2" long, at fighting trim she weighs 43lbs (mostly batteries).

She's built around a Swampworks (now defunct company) fiberglass hull, and some experimental (Kehr style) cannons. You will never find cannons like this anywhere else (6 total were ever made, and I have three of them) - though some of us are working on an update/improvement to the design...

 

USS Missouri and HMS Lion:

 

A glimpse inside of Missouri (also SMS Seydliz to Starboard, a Liberty Ship aft, and HMS Abdiel to Port) (My lovely wife is bored out of her mind in the background).

 

Missouri in the pits getting ready for a day of battling (the SMS Seydlitz in mid refit was brought along for show-and-tell. Sadly, she's not progressed much beyond this stage):

 

 

Some more internals shots. Missouri (left), WWI HMS Lion (right), and HMS Hood (Foreground).

 

[CT96]

Outfitting SMS Nassau:

 

Melee:

 

HMS Lion vs. HMS Lion

 

HMS Hood, Admiral Scheer, HMS King George V:

 

HMS Lion vs. SMS Hindenberg (pumping from damage), HMS Lion, HMS Hood, and Admiral Scheer:

Edited July 21, 2015 by CT96

[nabqrules]

One common question is "Do they sink?" Yes they do, and I have repair photos after Bismarck sunk.

 

Both these sections were full of holes and replacing the sections is actually fairly straightforward. The wood is balsa with silkspan applied (same cloth used in old model rc airplanes)

 

 

Smaller areas of damage we can just make plugs.

 

 

Cannons are custom. Bismarck's cannons were made by two fellow club members. The aft tandem cannon was a built specifically for Bismarck.

 

 

The front cannons are representative of most cannons though there are a few different designs.

 

 

Bismarck after refit.

 

[CT96]

Sometimes the moss gets the best of us...

 

Debugging some issues with Missouri:

 

Recovery of a sunk ship is as easy as picking it up...

[CT96]

SMS Nassau early in the build. She's based on a fiberglass hull:

 

A new set of experimental cannons for Nassau:

 

HMS King George V in the pits:

[APF]

Did anybody try to build some age-specific fire control into one of the ships? Like a camera in an optical RF, syncronize the guns for range and bearing and have a go at it?

 

This would probably be about as unfair as a 1920-ish Battleship with a dreyer table against someting around 1900 - oh, wait ...

Edited July 21, 2015 by APF

[rmgill]

I take it the guns are one shot or do they have a reload function? I take it solenoids to fire compressed air?

[nabqrules]

If you look on Bismarck's cannons you can see two holes in the middle of the cannons. Those are a feed ramps and that whole area is the "magazine" for the cannon. I can't remember offhand how many 1/4" ball bearings they hold each but at least 50.

CT96 can correct me if I'm wrong but There's a high pressure side and low pressure side to the CO2 system. The high pressure side is for the actuators to open a ball valve in the base of the cannon which then releases the low pressure side volume up into the cannon.

Edited July 21, 2015 by nabqrules

[Corinthian]

SO MUCH AWESOME!!!!!! *hides RC tanks*

 

How do you waterproof the electronics? How long is the running time for these things? How much is spent to build a BB? A DD?

SO MUCH AWESOME!!!!!!!!!!!!!!!!!!!!!

[CT96]

Did anybody try to build some age-specific fire control into one of the ships? Like a camera in an optical RF, syncronize the guns for range and bearing and have a go at it?

 

This would probably be about as unfair as a 1920-ish Battleship with a dreyer table against someting around 1900 - oh, wait ...

 

We have not instituted rules regarding period fire controls. The basic fire control is the Mk I Eyeball, though my intent is to do an actual fire-control system (first with local on each turret, then collectively on the ship) with microcontrollers and some sort of ranging sensor. Problem is the waterproofing...

 

I take it the guns are one shot or do they have a reload function? I take it solenoids to fire compressed air?

We use paintball cylinders to supply CO2 to run the cannons. Number of rounds is not constrained (except for Torpedoes) by historical load, but rather by how many you can fit in a magazine and how much CO2 you can carry. Missouri carries about 100-150rds per barrel, and a 20oz CO2 bottle (enough for several full magazine loads) - as well as about 35Ah of battery (she's effectively nuclear powered in this hobby - able to stay on the water for the day, assuming she doesn't need to come into port for repairs or to reload ammo).

 

 

SO MUCH AWESOME!!!!!! *hides RC tanks*

 

How do you waterproof the electronics? How long is the running time for these things? How much is spent to build a BB? A DD?

 

SO MUCH AWESOME!!!!!!!!!!!!!!!!!!!!!

 

We battle on freshwater ponds (not pools, not saltwater), and freshwater is a horrible conductor of electricity. Some people put in a great deal of effort to waterproofing, but it eventually fails anyway. So most (I think) just mount what electronics we can high in the boat so that they are not inundated until it's already going under, and use isopropyl alcohol to displace the water after a sinking (and it will dry without damaging the electronics).

 

How much is spent? As much or as little as you want to. The minimum is a two channel radio (steering and throttle), and a basic cargo ship (part of the game is that your team scores points for getting cargo runs around a designated course, while preventing the other team from doing the same). You can add a non-rotating bb cannon to a cargo ship to make a Q-Ship, which can fend off some of the smaller raiders (who will often slip by the battlewagons as they go after each other). The more bells and whistles you want to add, the more expensive it becomes. A fully equipped BB with all the primary and secondary cannons armed, rotating, under some form of electronic fire-control, with waterproofed video transmitter for the helm, 28-channel multiplexed......... they can get EXPENSIVE if you want them to be. Most of us don't go that far. All we win is bragging rights for the next meet, and anything that is taking repeated hits by 1/4" ball bearings and getting plunged to (sometimes quite a few) feet under water is going to need replacing often enough to not be worth putting a terrible amount of $ into.

[Guest Jason L]

I don't understand how those guns feed, do you just dump pressure into the magazine and it forces against the whole stack of bearings until they start popping out the tubing?

 

I've built a few solenoid powered guns, but they are all single shot, high pressure, high velocity affairs with a break breach you reload by hand.

[nabqrules]

It's gravity feed. Basically it's a tray with (in Bismarck's case) two feed ramps per cannon. Now in this picture the barrels are not attached. They attach with flexible hose to the two vertical "pipes". There is a lexan cover for the top of the magazine. Something to consider is this is very inefficient however accumulator sizing (the big white PVC section) is made to offset this inefficiency. CO2 also escapes through the feed ramp which is why there is RTV on one side of the magazine to serve as a cushion for bearings that do eventually fire out. However, the weight of other bearings in the feed ramp basically ensure that the bearing that is in battery goes out the barrel. There is tuning that is involved with pressures and adjusting a set screw in the breach to make sure the cannon feeds and fires properly. I'll have to get some better photos of Bismarck's cannons to better demonstrate their operation.

[Guest Jason L]

It's gravity feed. Basically it's a tray with (in Bismarck's case) two feed ramps per cannon. Now in this picture the barrels are not attached. They attach with flexible hose to the two vertical "pipes". There is a lexan cover for the top of the magazine. Something to consider is this is very inefficient however accumulator sizing (the big white PVC section) is made to offset this inefficiency. CO2 also escapes through the feed ramp which is why there is RTV on one side of the magazine to serve as a cushion for bearings that do eventually fire out. However, the weight of other bearings in the feed ramp basically ensure that the bearing that is in battery goes out the barrel. There is tuning that is involved with pressures and adjusting a set screw in the breach to make sure the cannon feeds and fires properly. I'll have to get some better photos of Bismarck's cannons to better demonstrate their operation.

 

Ah, gotcha. For some reason I thought the magazine was enclosed inside that grey PVC bit and the feed ramps were for refilling it. So a cup of some sort fits over what's shown in the picture?

[nabqrules]

It's actually just a flat lexan plate, there's a small hole drilled in it to fill the magazine and also a servo to control gun depression.

[Paul G.]

So when will you beta test aircraft carriers?

[rmgill]

Akula Submarines with Estes Rocket Powered Torpedos.

[nabqrules]

So when will you beta test aircraft carriers?

Hehe. Well actually there's a way in the rules to simulate aircraft with a fixed cannon, or use a Carrier unarmed as a merchant vessel that needs protection. Oh to have scale simulated aircraft would be epic...but we're talking tiny in 1:144 scale.

 

Akula Submarines with Estes Rocket Powered Torpedos.

The point is NOT to utterly destroy the other's ship. So no M80 depth charges either.

[CT96]

There are carriers that have been built and battled. Some even have small "dummy" aircraft that get catapulted at enemy ships (kamikaze style) to score points. Not as good as actually doing real damage... but oh well. The successful ones have been Midway and Essex classes... though some others have been built (Lexington actually had 8" cannons, so actually not a horrible surface combatant). I plan to eventually build a Yorktown (but more for the challenge of building one).

 

Part of the rules is "No pyrotechnics" e.g. no M80s, no explosives of any kind, no fire, etc. etc. etc. The point is to sink ships... not destroy them.

[Chris Werb]

Dumbass question, but how do you avoid players and/or spectators taking the occasional BB hit?

[CT96]

Dumbass question, but how do you avoid players and/or spectators taking the occasional BB hit?

 

You don't. Which is why we make anyone pondside wear eye protection. We've all taken some level of hits. I got nailed in the hand and point blank range by 3 1/4" ball bearings (roughly 1-2" from the muzzle). Hurt like hell, left some nice welts, but no real damage.

 

This reminds me of Hector Bywater and a number of his pal (Including possibly Frederick T Jane) doing something similar ont he serpentine pre ww1. Except in those days they had to do it via punched cards, rather than remote control, but it was spectacular all the same, even if predetermined.

 

Looks like good fun, but I dont think I could bring myself to watch one of mine sink.

 

I've actually never had mine sunk... but they are designed to be sunk and recovered and go for revenge in a matter of minutes.

[nabqrules]

This reminds me of Hector Bywater and a number of his pal (Including possibly Frederick T Jane) doing something similar ont he serpentine pre ww1. Except in those days they had to do it via punched cards, rather than remote control, but it was spectacular all the same, even if predetermined.

 

Looks like good fun, but I dont think I could bring myself to watch one of mine sink.

My Bismarck did sink, and it was actually due to my pump battery not having enough capacity to pump for 30 minutes as someone got a below waterline hit early on. I noticed that the water stream wasn't as high as it should be and started her toward shore. I had to try out all the electronics but everything worked fine. I wasn't very happy and I had a dark cloud over my head until I was able to confirm the radio worked, but that was my first time out and if I get her out again in a battle It won't be so...traumatic. Looking back, Bismarck sinking was actually a lot of fun.

[Guest Jason L]

Can you integrate the radio and other electronics into mini Pelican cases and then just drill water proofed pass-throughs for wiring? I've made useful water resistant field stuff using Pelican cases as a base.

 

You can also get extremely cheap cameras on chips now that you could integrate into the turrets for aiming as well that you can beam back to shore via a Pi and wifi.

 

For a while I was blowing up those little cameras all of the time. And then play the fun game of find the SD card in the debris.

Edited July 27, 2015 by Jason L

[CT96]

Lots of people have built or otherwise acquired "Water proof cases" - and they work well, right up until you trust them, then they fail. Catastrophically. Usually at the end of the season, and you won't notice until you pull things out in the spring and discover that none of your electronics are working anymore because they've been corroding in water all winter....

 

Water resistant is great... for a little bit of depth. It is surprising how fast water starts to infiltrate as you go deeper. The deep sea ROVs typically are filled with mineral oil or some other non-conductive uncompromisable fluid. I've thought about going that route, but never have gone so far as to do so.

 

I have an entire JIRA/Confluence project covering the development of just such a targeting and control system as you suggest. I haven't fielded it yet - mostly because I've not had the time in the last year or so with changing jobs and moving. Maybe this winter? (hahahahahahaha)

[nabqrules]

I have a "sealed" compartment where the receiver, speed control and the cannon servo reside. One aspect of the rules is that we can't have anything buoyant to slow the sinking of the ship, which a full watertight compartment would end up being. The compartment I have will prevent water from touching the receiver right before the ship sinks. It worked well and I had control until she sank.

 

When I got Bismarck ready there were not as many options available for electronic as there are now. There are some videos from one of the other clubs when they put a small camera on board,