Torpedoes Los!
Note - A word of caution: These torpedoes are filled with the same type of liquefied gas used to dust a computer keyboard or to spray paint with an airbrush. The liquid gas is cold as it leaves the can - cold enough to cause painful frost burns. While its pressure is much lower than CO2, keep in mind that the heat of a warm day or direct sun will cause the gas to expand. The result is an increase in pressure in the torpedo body. Torpedoes should NOT BE LOADED and then allowed to sit in the sub in the sun. The increased pressure will eventually “cook off” the torpedo - causing an unintended launch ~ possibly into the neighbor's baby stroller or an unsuspecting bystander's eye (can you say “Lawyers' feeding frenzy?”) I also follow the SubCommittee's rules for pressurized tanks and fill the torpedo well away (and pointed away) from bystanders and wear safety glasses. These babies can make like missiles and fly through the air too! (See above “feeding frenzy” warning.) The rules are posted at www.SubCommittee.com.
I place my sub in the pond after loading torpedoes and wait for a turn to run with the boat and torpedoes sitting in nice cool water. It might also be wise to put some sort of pin or cotter key locking device that would block the torpedo from leaving the torpedo tube after it's loaded until the sub is placed in the pond.
Remember SAFETY FIRST AND SAFETY ALWAYS!
I place my sub in the pond after loading torpedoes and wait for a turn to run with the boat and torpedoes sitting in nice cool water. It might also be wise to put some sort of pin or cotter key locking device that would block the torpedo from leaving the torpedo tube after it's loaded until the sub is placed in the pond.
Remember SAFETY FIRST AND SAFETY ALWAYS!
How I make torpedoes - by Mike Dory
Almost everyone who has launched an RC sub in a public place has been asked what I call “The questions”. They are as follows: “Does it really sink?” (Hopefully not!) “How deep does it go?” (All the way to the bottom if I'm not careful.) “How fast does it go?” (“A scale speed of over 100 mph” always wow's them.) “How much did it cost?” (More than your bike and less than your Dad's car.) And “Does it shoot torpedoes?”
One of the biggest crowd-pleasers for a model submarine is working torpedoes. These torpedoes are relatively inexpensive to build, very durable, easy to maintain and ALWAYS please the crowd! This is how I build torpedoes for my RC model submarines. This isn't the only way and may not be best way to do it, but it's what works for me. I make no guarantees as to safety or anything else. If you decide to make these torpedoes, you are on your own, sailorman!
Okay, now that the disclaimers are done, here's what I use when I make my torpedoes:
Aluminum tubing 5/8” X 6 1/4” with .02” wall thickness for the torpedo body, available in most well stocked hobby and hardware stores.
Hardwood dowel rod from any good hardware store or lumberyard, cylindrical aluminum block to serve as a base for the tire valve Schrader tire valve to fill propellant into torpedo body Hot Stuff brand CA adhesive, an old .035” drill bit for the firing pin Nyrod with threaded brass endpiece to pull the pin Nylon rod for nozzle Sheet styrene plastic for fins.
The torpedo is 8.75” X 5/8” diameter and is divided into three parts. The nosepiece is a bullet-shaped piece of hardwood dowel rod glued into a 2.25” section of 5/8” aluminum tubing. The next 4.75” is aluminum tubing and the aluminum tail section is 1.25 with .25 of that fitted into the end of the tube. A Schrader tire valve (available at any auto parts store) is mounted in a hole in a cylindrical aluminum block that is glued and press-fitted into the aluminum torpedo body using a CA adhesive product called “Hot Stuff”. I remove the rubber part of the valve that goes into the tire rim with a lathe.
One of the biggest crowd-pleasers for a model submarine is working torpedoes. These torpedoes are relatively inexpensive to build, very durable, easy to maintain and ALWAYS please the crowd! This is how I build torpedoes for my RC model submarines. This isn't the only way and may not be best way to do it, but it's what works for me. I make no guarantees as to safety or anything else. If you decide to make these torpedoes, you are on your own, sailorman!
Okay, now that the disclaimers are done, here's what I use when I make my torpedoes:
Aluminum tubing 5/8” X 6 1/4” with .02” wall thickness for the torpedo body, available in most well stocked hobby and hardware stores.
Hardwood dowel rod from any good hardware store or lumberyard, cylindrical aluminum block to serve as a base for the tire valve Schrader tire valve to fill propellant into torpedo body Hot Stuff brand CA adhesive, an old .035” drill bit for the firing pin Nyrod with threaded brass endpiece to pull the pin Nylon rod for nozzle Sheet styrene plastic for fins.
The torpedo is 8.75” X 5/8” diameter and is divided into three parts. The nosepiece is a bullet-shaped piece of hardwood dowel rod glued into a 2.25” section of 5/8” aluminum tubing. The next 4.75” is aluminum tubing and the aluminum tail section is 1.25 with .25 of that fitted into the end of the tube. A Schrader tire valve (available at any auto parts store) is mounted in a hole in a cylindrical aluminum block that is glued and press-fitted into the aluminum torpedo body using a CA adhesive product called “Hot Stuff”. I remove the rubber part of the valve that goes into the tire rim with a lathe.
Trim the valve thread
A bit of the threaded end of the valve is trimmed off to increase the torpedo's buoyancy. The valve is for filling the torpedo with compressed liquid propellant like Propel or Super Duster. I switched to Super Duster in my sub's ballast systems a number of years ago since it seems to be less corrosive to the ballast valves.
Hot Stuff baby tonight!
You can see I have trimmed of a little bit of the threaded end of the Schrader valve to cut down on weight. The aluminum block it is mounted in can be seen where the black paint has scraped off a little.
I use “Hot Stuff” to adhere the aluminum block onto the torpedo body because it is the only CA glue product that is marketed as being truly waterproof. You don't want your Schrader valve caroming out the end of your torpedo due to a water-failed glue joint and winding up in the eye of the curious six-year-old son of a lawyer standing nearby! The last 1.25” of the torpedo is tapered down to a diameter of 3/16” at the exterior if the stern. I drill the inside of the torpedo at the rearmost part of the end in a taper matching the exterior with the final .75” left solid.
I use “Hot Stuff” to adhere the aluminum block onto the torpedo body because it is the only CA glue product that is marketed as being truly waterproof. You don't want your Schrader valve caroming out the end of your torpedo due to a water-failed glue joint and winding up in the eye of the curious six-year-old son of a lawyer standing nearby! The last 1.25” of the torpedo is tapered down to a diameter of 3/16” at the exterior if the stern. I drill the inside of the torpedo at the rearmost part of the end in a taper matching the exterior with the final .75” left solid.