Rowen has used this technique on his models to control brushless motors. He found that using differential motor control for steering could be difficult. The brushless motor response is so rapid it is impossible to do anything gently. For steering he tends to use rudder control on the LH stick when running at slow speed or when in confined waters, and turns using Elevon differential motor control on the RH lever at speed or on open water. Differential control will probably be smoother when using brushed motors.
In his article above, Rowen mentions the use of a LED driver. These are extremely useful devices and can take all the headaches of figuring out how to wire your LEDs. Simply insert one into your circuit and your 20mA LED will light up as it should.
This simple device limits the current through itself to 20mA. When a voltage is applied (anywhere from 2 to 45V) it will actively adjust it's own resistance to allow just 20mA (+/- 3mA) to pass through. This makes it a perfect replacement for current-limiting resistors in LED circuits, and you won't have to calculate resistor values or worry about a varying voltage source.
The current limiter can be placed anywhere in the loop with LED's, but needs to be placed with the proper orientation, or it and your LED's could be damaged. The board has 0.032" solder holes which can accommodate wire down to 22AWG (tightly twisted) or standard 0.1" header pins. Note that at least ~2V across the current limiter is required for proper operation - below that and the current output will start to decrease and the LED's to dim. Multiple current limiters can also be placed in parallel to add current (40mA, 60mA, etc...).
Units are provided on a scored circuit board that can be broken apart using pliers and/or strong fingers. Size: 0.334 x 0.100 x 0.077".
More information can be found at: https://lighthouseleds.com/20ma-led-current-limiter-driver.html .
If you will not be using your LiPos for more than 24 hours, then put them into storage. Charge or discharge them to 3.8V per cell, securely place them into a LiPo Safe Bag, and find a shaded area that is at room temperature.
Remember, if you treat your LiPos well, they will treat you even better. When properly maintained, LiPos can typically last you up to 2-3 years.
Do take care to install neatly arranged, easy-to-trace wiring throughout the model. Solder all connectors to insure current flow and keep all wires up out of the bilge area to prevent exposure to normal bilge water.
Regarding year-round storage of Lipo batteries:
Save your servo wires from chaffing on bulkheads and when passing thru fiberglass holes by making little grommets out of scrap fuel tubing. Slit them length wise and slide over servo wires. Keep them in place with wire ties or a little Zap glue.
Member's tip from Garth: Use an empty Tylenol (or similar) bottle to house your receiver and to make doubly sure it doesn’t get wet, seal it with tape or Silicone.
Elevon control - an explanation by Rowen
http://tinyfixation.blogspot.com/2012/11/tutorial-tape-wiring-dollhouse-basics.html
Rick told us about some epoxy which he had obtained from Noah's Marine in Etobicoke and was very economical, at $28.30 for 12oz. Look for Ark Composites Epoxy Repair Kit.
Hints and tips - LED drivers: eliminate the resistor.
Most of us are delighted when our model just responds to radio signals and performs properly. Typically, we use a “lever” style transmitter (Tx) and on a twin motor vessel, if seeking individual motor control, one motor is controlled by the up/down movement of each lever. This works well but has some limitations. Both hands need to be used and rudder effect is easily masked by inadvertent motor operation. This is particularly apparent on faster models with a brushless motor installation.
There was an article published in “Model Boats” magazine in March 2019 suggesting another approach. All of our RC equipment was generally developed for model aircraft, for that is where the volume market is. However, sometimes features are offered that boaters would not usually use. On some of the more sophisticated Transmitters (Tx) both “Elevon” and “V-tail” mixing are available. These link two radio functions together so one control lever can operate both features. I will describe the “Elevon” as it is the one I use on my Flysky Tx, although both functions are offered.
"Elevons" are control surfaces on delta wing aircraft where the functions of elevator and aileron are combined. My Tx is the “Mode 2” style where elevator and aileron controls are on the RH lever. In aircraft with separate wings and tail, the Forward/Back stick movements operate the 2 elevators and cause the aircraft to pitch up or down, and side/side movements operate the 2 ailerons and cause the aircraft to roll. When the 'elevon' control method is used, the same stick movements cause the same aircraft motions but operate only 2 elevons.
On a model boat, elevon control puts both ESCs on the RH control lever. Moving the lever up operates both screws in the forward direction and down into reverse. Going from side to side speeds up or slows down either motor, so the boat goes in the direction the lever dictates. Rather more intuitive than before. After setting this function up and then testing it, I decided it works well. This was accomplished by:
Your Radio instructions should give detailed information on setting up the radio.
Confederation Marine Modellers
Stick a piece of Velcro to a suitable place on the hull or frames, then arrange the wires across it. Trap the wires by pressing the matching Velcro piece over them.
If we have a need for 300° rotation in a servo it has been necessary to get complicated to achieve that. Even getting more than 90° has required the use of a servo stretcher added to a standard servo. This 'goBilda' servo is capable of 135° out of the box. With the addition of a servo stretcher it will produce 300° rotation.
The servo costs US$28 from Servocity. and gobilda.
Affix two brass bolts so that they protrude from the transom. Connect these to your battery terminals, if desired via a changeover switch, with the positive (red) terminal on the port side, and the black (negative) terminal on the starboard. These become convenient charging terminals. They could also be placed on deck and take the form of brass bollards or cleats. This idea eliminates the need for another terminal in the radio box, where a charging socket would usually be. Use alligator clips to connect the charger.
(latest at the bottom)
Some years ago it was available from Harbor Models in the USA, but not recently.
It is now available from two suppliers in the UK, Howes Models and Cornwall Model Boats.:Howes Models F14 and Cornwall Model Boats F14. This version contains one twin-stick, ideal for twin-prop control, and one single stick. It is an 8-channel radio. The single stick could be replaced with another twin-stick if desired, available from Robbe in Germany.
These versions operate at 40MHz so they must be converted to 2.4GHz for use in North America. Fortunately this is fairly easy to do using the Assan 2.4GHz hack module available from Hobbyking: Hack module., a conversion that I have already done. Step-by-step instructions can be found on Youtube.
That's the good news. The bad news is that the radio will set you back £200 (~CDN$330) and the Assan hack module US$50 (~CDN$63).
Update: Mar 2023. The Robbe radio and the Assan module appear to have been discontinued but you may be able to find an equivalent via the internet. Roy C.