Author: Frank Pittelli
E-Mail: pittelli@rssi.com
Date: May 3, 1995
The ships are built to rigid standards that ensure that they can be damaged easily and can be sunk if sufficient damage is sustained. Low-powered BB cannons are used to poke holes in the 1/32" balsa wood that is used on the hull of the ship. Ships also have homemade bilge pumps on-board that can be used to pump out as needed.
However, if the rate of incoming water exceeds the pumping rate, the ship will fill with water and eventually sink.
By rule design, in order to take your ship off the water, a captain must start a 5-minute timer. During that 5-minute period, the ship cannot fire on any other ship, but it may be fired upon. When the timer expires, the captain can touch the ship and remove it from the water. Generally, experienced captains determine when their ship has suffered too much damage and begin their timers early enough to prevent the ultimate disaster: a sink.
On numerous occasions, ships have sunk a few seconds before the timer has expired.
Most battles are conducted on shallow ponds, which allow the captain to wade in and salvage the boat. Sometimes, captains attach floaters to the superstructure with a long, strong line, in case they can't locate the boat. On a couple of occasions, such lines have deployed during a battle, tangling in the props of one or more ships.
Lots of spare hulls??? We have some hulls that have been battled and repaired for 10 years!!!!
We generally apply a single layer of 000 silkspan to the inside and another layer on the outside, using either clear dope or lacquer. I prefer standard brushing lacquer because I can buy it in quart sizes and it doesn't stink as much as clear dope.
In either case, that is sufficient to waterproof the hull, given a coat or two of paint on the outside. Our rules require a specific "drop test" to ensure that hulls are not too hard, so it doesn't pay to use too much paint anyway.
When hull holes are repaired, we simply dab on some Ambroid glue or clear dope and apply a small silkspan patch. That drys in minutes and is waterproof as well. After a hull has had too much damage and there is more silkspan than balsa (roughly after 5 days of normal battling) we strip off the balsa and start over again. This process is easier if all of the ribs and deck rims have been sealed with polyester resin or epoxy before the balsa skin is applied.
Some battleships have rotating and/or elevating guns depending on the preference of the captain. I have used both and find rotating guns useful in some situations, like shooting a ship that is caught along shore, but generally they require more room in the boat and require more time to keep them working properly.
The fastest firing sequence recorded on video showed a rate of roughly 5 shots per second, sustained over a 6-8 second period. Most of the shots were on target and the recipient battleship sank in less than 5 minutes with one of the strongest pumps running non-stop.
And don't let the initial cost discourage you. Many rookies borrow part or all of a ship from a veteran and battle it for a year. That leaves only the operating costs, plus time spent fixing the boat and repairing old parts. It's a nice way to try it out before spending too much money. (But remember, your time and pleasure are worth something too.)
Approx. Cost Of Rookie Heavy Cruiser
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1. A hull, with 1/32 balsa sides 15.00
2. Hardened superstructure 5.00
3. BB cannons (2) 10.00
4. CO2 Disposable Tank Adaptor 15.00
5. CO2 regulator (150psi max) 15.00
6. CO2 values (2) 10.00
7. Batteries (Main motors, pump(s), RX) 40.00
8. Main motors (2) 5.00
9. Bilge pump (1) 5.00
10. RX and servos (4 channel) 100.00
11. Forward/Reverse Speed Control 5.00
12. Prop(s) and shaft(s) 5.00
13. Rudder(s) 3.00
14. Paint and silkspan 10.00
15. Glue 10.00
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Building Cost 253.00
Operating Costs For Rookie Year (2 Regional Events)
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1. IR/CWCC Membership 6.00
2. NAMBA Membership and Insurance 40.00
3. Box of BBs (5000) 6.00
4. Disposable 2oz CO2 Cartridges (25) 50.00
5. Battery charger 5.00
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Operating Cost 107.00
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Total Rookie Cost 360.00
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The pair of microswitches is wired so that when both switches are up, the negative side of the battery is sent to both poles of the motor. When either switch is depressed, the positive side of the battery is sent to one of the motor poles.
Actually, subs are allowed but they don't have enough firepower to make a difference and they are very small in our scale. Some have been used over the years, but primarily as a novelty. Battleships and battle-cruisers control the R/C combat seas.
The purpose of the interrupter is to select "one" BB at a time when a CO2 value is opened. It consists of a "tee" compression fitting, which has three openings, two on each end and one in the middle at 90 degrees to the other two. The magazine attaches to the one in the middle and the top opening leads to the breach. The bottom opening is used to house either a spring-loaded piston or two 1/4" ball bearings. Ball bearings require less precision and maintenance, but the spring-loaded piston allows more rapid firing rates. In either case, when gas is applied to the bottom opening (through the end cap) the piston or ball bearings rise up to block the opening from the magazine. This allows only one BB (the one on top of the piston or ball bearings) to move into the breach and fire. When gas the gas is released, the piston or ball bearings drop and another BB is allowed in the chamber above them, ready for firing.
A small piece of 1/4" copper or brass tubing connects the upper opening of the interrupter to the breach. The breach can be made using either a piece of surgical tubing (called a "geek" breach) or a compression fitting with an internal "o-ring". The geek breach is simpler to make, but it cannot be adjusted for "hardness" (the amount of pressure needed to make the BB fire) and the sometimes break. The o-ring breach works by forcing the BB through a rubber o-ring that is slightly smaller than the BB. As pressure builds behind the BB, it pushes the o-ring wider and eventually "pops" through, proceeding down the barrel. The o-ring breach is harder to "perfect", but it can be adjusted at lake side by adjusting the tension placed on the o-ring by the barrel. This is good for changing pressure conditions (pressures build with higher temperatures) but it requires constant attention before a battle.
Very Large Battleships 7 units Large Battleships 6 units Battleships 5 units Battle cruisers 4 units Heavy cruisers 3 units Light cruisers 2 units Destroyers 1 unitShip speeds are also divided into classes, with the following common classes (all speeds measured on a 100 foot course)
Battleships (over 720') 24 secs Battleships (over 600') 26 secs Battleships (under 600') 28 secs Battle cruisers (over 660') 24 secs Battle cruisers (under 660') 26 secs Heavy cruisers (after 1922) 24 secs Heavy cruisers (before 1922) 26 secs Light cruisers 23 secs Destroyers (over 300') 22 secs Destroyers (under 300') 23 secs
Sink points are awarded to any ship that sinks because of battle damage, is declared sunk (without totally sinking) or is withdrawn from battle between sorties. Points are awarded based on the size of the ship:
Class 7 1100 points Class 6 1000 points Class 5 900 points Class 4 800 points Class 3 700 points Class 2 400 points Class 1 200 pointsIf a ship is "declared sunk" by the captain, the sink points are multiplied by 1.5. If a ship is withdrawn, full sink points are awarded.
Finally, if the ship breaks a specific set of battle rules (such as ramming another ship and causing damage) then penalty points are awarded depending on the severity of the infraction.
PS. The goal is to earn the "fewest" number of points.
The yearly national competition "NATS" moves around from year to year. In past years, it has been held in Bowie, Maryland (90 & 91), Orlando, Florida (92), Huston, Texas (93 & 94), and St. Louis, Missouri (95). NATS is a week-long event, held on the second full week in July. In recent years, attendance has been anywhere from 20 to 30 captains.
BBs don't have as much power, which makes them safer for spectators. BB cannons also use the "pressure" of gas to fire the BB.
Many captains buy props from commercial model outfitters. I have found that such props are too expensive and tend to fall apart with heavy use (ie. grinding them into a gravel beach). I have been building my own props for the last 4 years out of a 3/8" diameter brass cylinder about 5/8" long. A 1/8" hole is drilled down the center and two or three slits are cut on the outside using a hacksaw blade or a dremel cutting wheel. Then, simply cut some triangular blades out of brass sheet, solder them in place and file them and bend them to your taste. At IR/CWCC scales and speeds, such rudimentary props behave just as good as the fancy store bought models.
All ship models use a "stuffing box" to allow the prop shaft to pass through the hull of the boat. Most people use an 1/8" brass rod for the shaft and a 3/16" brass tube for the shaft housing. A small piece of 5/32" tubing is solder inside the ends of the 3/16" tube to support the 1/8" shaft. If a little bit of grease or vasoline is inserted into the tube before the prop shaft, then no water will be able to force its way up the tube. (By the way, this is essentially how real prop shafts are installed also.)
A number of JPEG format pictures were posted by Kommodor@aol.com to the alt.binaries.pictures.misc newsgroup on May 1, 1995.
(From filipg)
These are also available (FOR A LIMITED TIME) for those on the World Wide Web (WWW) at URL:
http://alpha.smi.med.pitt.edu:9000
Generally, you should use channels in the 75Mhz region, which are considered ground and sea frequencies. There are also a few channels in the 27Mhz band which can be used.
The AMA frowns on the use of airplane frequencies for anything except airplanes. Practically speaking, however, if you don't see or hear an R/C airplane overhead and you know that there are no landing fields within a few miles, then there isn't any reason not to use an airplane freq.
Keep everything as simple as possible and work on one system at a time until it works to your satisfaction. I always build things in the following order:
I think filling all hollow areas with styrofoam would be an excellent idea.
All of these restrictions have been developed to guarantee that ships CAN sink. It might not be obvious, but R/C warship combat isn't any fun unless you can sink someone else AND you can be sunk by someone else. In fact, you haven't "tasted combat" until you've escaped sinking by a few seconds or fractions of an inch.