mSR X

What an exciting day for micro R/C hobbyist. Hobby King just introduced a new module that is compatible with Spektrum DSMX and DSM2 technology for your Turnigy 9x and other radio that accepts JR style module.

OrangeRX DSMX/DSM2 Transmitter Module

It’s a full range system too. So you can fly all the Horizon Hobby DSM2 and DSMX BnF system with your Turnigy 9x.

Price is decent at $30.

New Hobby King OrangeRX DSMX and DSM2 Transmitter Module for the Turnigy 9x

Thanks to Julian for giving me the heads up on it’s availability. :)

In almost all aspect of life, having the right tool makes the job much easier. When flying micro helicopters and quads, everything has to be micro sized in order to avoid adding unneeded weight that may robs the motor of it’s performance.

For wires, magnet wires, also known as enamel wires, are a must have in your tool kit. The bigger brand names such as Horizon Hobby with their Blade lineup of heli, uses magnet wires for their antennas and for the tail motor. Nine Eagles is another manufacturer that uses magnet wires to extend to the tail motor.

I find that a good gauge for these wires are about 30-32 AWG, measuring about 0.0085in or 0.02mm. You can find magnet wires if you search for them online. Locally, my Fry’s Electronics and Radio Shack have them in spools that will last you a long time.

Alternatively, you can find the right gauge magnet wire in small motors often used in toys. Also, fans used in computers is often another source, though I find they can sometimes be thinner than 32ga.

Perfect 32ga magnet wire for these small motors

Simply take apart the motor and unravel the wire. Taking care not to rub against the rough armature and accidentally nick the enamel coating of the wire. One motor yields a lot of wire. After taking them off, you’ll see they are wavy and kinked.

A trick I use is to simply hold a section of the wire between each hand and running them back and forth against the edge of a a cutting mat, metal rod, or any edge that will not nick the wires and will not get damage if the wire start to cut into it. This trick will quickly straighten out the wire with a couple of passes. See the photos below…

Rubbing the wires back and forth along the edge of a table, metal rod or cutting mat will straighten out the kinks of the wire

To solder these magnet wires, you have to remove the enamel that coats the copper of the wire. The enamel is to prevent the wires from shorting out while wound up in the motor. Some people may scrape the thin enamel coating off. The trick I learned is that the enamel coating can be quickly burned off and the wire tinned at the same time using solder.

I put a blob of solder on the tip of my iron and touch the end of the magnet wire to it.

Touch the end of the magnet wire to a solder blob for a second to strip the enamel and tin it at the same time

It takes but a second and you get a perfectly tinned tip, ready to be solder. Easy peasy. :)

Perfectly tinned magnet wire without any hassle

Another tip for you. If you want to lower the overall resistance and thicken up the gauge of the wires, you can twist a few strands of the magnet wires together. I do this by putting one end into the power drill and hold the opposite end. The hand held power drill will make a perfect twisted bundle of magnet wire.

Put a few strands or more of magnet wire to a power drill and it will create a perfect twist

Here, you can see that three 32ga magnet wire twisted together has more copper than the original stock wires that feeds through the v929 boom. Because each wire has the enamel coating, despite having more overall copper, the twisted bundle is equal to the thickness of the original wires with it’s insulation. Which means you can still feed a positive and negative pair through the carbon fiber boom.

Three strands of 32ga magnet wire to replace original stock v929 boom wire

I like to use the magnet wire because it’s cheap, lightweight and it’s coating looks like anodized metal.

One final trick, for aesthetics, I will use the same color for positive and negative. To keep track of the polarity, I simply mark the each ends of the negative wire with a black sharpie so I properly solder it to the negative terminal. Twisted togther, they looks like an performance “upgrade.” :D The cooler looking it is…the faster it goes. ;)

That’s all there is to it.  Hopefully this post helps you guys. Happy modding!!!

I am pretty certain I am not the first to take a sharpie to the surface of a motor, but I’ll share this technique anyways. My wife gave me a bag of Sharpies last night and this was the first idea that came to mind.

I find that the large, wedge shaped Sharpie, stroking in one direction gives a nice even coverage. Here’s a comparison of the larger, wedge shaped Sharpie versus the standard conical shaped Sharpie on the right.

Wedge shaped/chisel Sharpie on right versus standard medium tipped Sharpie

Using the larger Sharpie, I find going in one continuous direction gives a nice even coverage.

It dries to the touch and can be handled without bleeding onto your hands once it’s dried. Unlike paint, the Sharpie allow the lustre of the metal to come through and simulates that anodized aluminum look. And because it’s such a thin layer of dye, it still allow the motor to cool off properly.

However, the drawback is that the faux anodized finish can easily be scratched or scrapped off. Luckily, it’s easy to retouch the scratched up parts. I think the results speaks for itself. It looks pretty nice when all is said and done. Very little effort and zero cost versus the bling, bling anodized CNC parts we hobbyist are always drooling over.

Just wanted to share the evolution of my mSR X brushless mount.

I find it’s easier to design on the computer. A digital caliper is a great tool to transfer the measurements into your graphics program. A CAD program is ideal. I am more familiar with Illustrator, so that is what I used. If you can scan your object, you can use that scan as an overlay to trace it’s physical dimensions. Doing it this way allow you to make precise changes on the computer. The low tolerance and need for higher precision is very important at the size of these micro helicopters.

Here’s a previous design for the AP-03 motor. Unfortunately, this motor wasn’t enough power for the mSR X.

Prototype of the mSRX AP03 brushless motor mount. The AP03 doesn't have enough power for the mSRX.

Then print and cut out some on paper. Or you can print onto label paper that you can peel and stick to a plastic credit card. This allow you to cut out the prototype with a xacto knife and scissors. You’ll find you need to do a few to narrow down the design.

Various mSR X AP03 prototypes on paper and plastic

Once you’re happy, you use the same method of printing onto a label paper and sticking it on top of the material you want to make the mount out of. I used 0.8mm weaved carbon fiber sheet. I used a dremel and freehand the cut out and a file to clean up the shape. It wasn’t too difficult work, and didn’t take too long at all. However, if you have access to a CNC router, the prototyping stage goes by so much faster and easier.

Here’s a couple of photo of the final result. I consider it a prototype, but it could qualify for production work. It’s very polish and wowed the owner of the mSRX and friends who have gotten to see it in person.

I felt that the stock mSR X was very underpowered the first time I got to fly it. Because it was underpowered, I couldn’t bail out of bad situations. The positive quality of the mSR X is quickly the flybarless heli respond to your cyclic command. It was near instant. It’s a pity that it lacks power. On top of that, there seem to be a huge problem where the stock brushed motor tend to die very early deaths. There’s a whole thread from owners tracking the issue.

After the mod to a brushless motor, the mSR X finally has the pop I like to see in my micro heli. I personally think it should have came this way from the factory. It is definitely worth it for those with mSR X. The brushless ESC, motor, mount and wires all weigh less than the stock brushed motor. Isn’t that amazing?

Stay tune for the rest of the how to’s on this series. Until then, take a look at preparing for flashing the ESC here: Silicon Labs USB Toolstick Mod for BLHeli Flashing