Micro Airsoft Cannon Diy for Rc Plane

There are individuals who push tools, materials, and craftsmanship to the limit in the world of micro RC shipping, and [Martin Newell] gives some insight into the kind of work that goes into making something like a ane:96 scale P-51 Mustang from scratch. The tiny aeroplane is 100% flyable. Information technology even includes working navigation lights and flashing cannons (both done with 0402 LEDs) and functional, retractable landing gear. It weighs an incredible 2.nine grams. Apart from the bombardment, everything in the plane was built or assembled from scratch. A video is embedded beneath.

[Martin] shares some of the techniques that went into the many specialized parts of the airplane. Two documents (Part 1 most techniques used for small aircraft and Part 2 virtually the P-51 Mustang pictured) are worth a read. In true craftsman style, he's aware that while he rolled his own solutions and wasn't aware of whatever similar prior work, he would exist surprised if none of his innovations had ever been done by someone else before.

At such pocket-sized scales many problems need re-solving, like electrical connectors. All the usual off-the-shelf connectors are far besides big or heavy to go along such a small device where every fraction of a gram counts. Whenever possible, connectors are avoided entirely merely sometimes — like to connect the custom-wound motor — it needs to be done. In these cases [Martin] made his ain.

ultra-micro-connectors

Micro plug and socket [Source: Warbirds at 1:100 Scale by Martin Newell]
The pin on the left of the photograph above is made from a 0.1″ length of 0.010″ bore brass rod soldered to a wire pb, supported with 0.020″ ID heat shrink tubing. The socket on the right is a 0.i″ length of plastic insulation from 32 AWG wire, with the strands from the other wire drawn through and effectually, and covered with 0.020″ shrink tubing. Contact is made by the contumely pin (left) beingness squeezed against the multiple strands inside the plastic insulation tube (right).

Another innovation was hinges for the control surfaces like the rudder, ailerons, and flaps. Unsatisfied with plastic hinges, [Martin] made his own nearly-frictionless and nearly-weightless ones consummate with re-centering springs. Each weighs 1.six milligrams.

hinges Control surface hinge blueprint [Source: Warbirds at 1:100 Scale by Martin Newell]
The hinges on the left are made from 0.008″ nickel wire and a 1 mm length of 0.four mm plastic tube. The centering spring is a nylon bristle from a paintbrush, which [Martin] observed was pointed on one end and seemed quite springy. The tip of a single bristle is inserted into the model and by adjusting how far it is inserted, the amount of maximum deflection the command surface is allowed can be controlled. Once satisfactory, information technology is secured with a tiny bead of glue.

[Source: microflierradio.com]

A sample micro actuator. They become even smaller. [Source: microflierradio.com]
Servos are the usual ways of actuating control surfaces like rudders and ailerons on model aircraft, but a plane similar this ane is far too small and lightweight to carry even the smallest servo. Instead of servos, these micro aircraft utilise tiny coils and magnets as actuators. They exert no forcefulness unless active, which means that whatever control surfaces they connect to need to provide their own ways of re-centering and holding stable when idle. This type of actuator is common in micro shipping, merely understanding the design gives insight into why [Martin] designed the hinges and centering springs the way he did. Similar actuators are visible on the bottom of the wings in the video embedded below. They are responsible for moving the two ailerons, and the two flaps. More are present on the rudder and elevator at the rear of the airplane.

[Martin] says that past far the well-nigh difficult office was the retractable landing gear. The solution uses 0.001" diameter Nitinol musculus wire. Muscle wire can exist stretched virtually 5%, and then when information technology is heated to a higher place a critical temperature by passing a electric current through it, it exerts a considerable forcefulness in attempting to contract back to its original length. Past using 2 lengths of muscle wire, a pull-pull mechanism can be built in which the contraction of one wire has the effect of stretching the other while either raising or lowering the landing gear at the same time.

optimized-landing-gear A push button-pull organisation using nitinol "musculus" wire provides the raw power behind actuating the landing gear, merely required a pregnant custom assembly to piece of work.

All the same, that was much easier said than done. [Martin] explains:

"Unfortunately this appealingly simple machinery is fraught with implementation issues when trying to meet the design requirements. One of them is that after stretching 1 wire by contracting the other, when the electric current is stopped the contraction recoils about 30%. Therefore a lock is needed to keep the wire fully stretched. Then a 2d lock is needed to secure the landing gear upward or down, and then that sharp sideways forces exercise non result in whatsoever forces back on the muscle wire, which could plummet the landing gear. These requirements were met with a unit that weighs about 400 milligrams. The muscle wires rotate a 0.030" diameter capstan ninety degrees. The muscle wire recoil is countered past an over-center spring interim on an idler at the finish of an arm fastened to the capstan."

[Martin] goes into detail well-nigh the whole retract assembly for the landing gear in Office two of his documentation.

A familiar question has been whether these planes are available for sale. The answer is probably also familiar to people who make such labor-intensive things: [Martin] says they are not for sale, at least not from him. If he did offer them for auction, nobody would pay the cost he would ask because of the corporeality of work involved.

Information technology took [Martin] about a year to develop and build the ane:96 P-51D Mustang, and he just recently shared a video of the tiny airplane flying on his YouTube channel. It is embedded beneath.

[Martin] demonstrates all 8 channels of command in the video below:

Speaking of scratch-built RC shipping, nosotros previously covered a projection dedicated to 3D press parts for a flying RC aeroplane, complete with in-depth testing and analysis. RC hobby aircraft is an example of a field that, while filled to the brim with off-the-shelf systems, is nevertheless home to individual innovation and DIY spirit.

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