Space Cowboy Design SCX-230 LowPro

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On my recent order of cut carbon from Armattan Productions I included a GoPro mount kit which suits the SCX-230. I’ve been flying this copter for some time now and am very happy with it. It’s a long way from ‘latest and greatest’ gear wise but it is built with quality components and the experience has been better for it. Now being able to watch some of my flights in HD and share them with others has been great fun. To that end this post is primarily to share link some of my recent videos (no edits, directly from a GoPro Session 4).

My primary flying site has a great mix of open spaces and trees:

The rig also came with me on a recent camping trip:

I think I got very lucky with this crash. The only damage was the two front arms, I didn’t even need to straighten a prop:

Fresh PepperF1SH frames

DSC04759I’ve received some freshly cut carbon from Artmattan Productions. That means it’s time for some new PepperF1SH builds, I’ve got plans for at least 3 more. Also seen in the photo above are some titanium screws purchased from AliExpress.

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My twig frame as seen mechanically assembled here is unproven, but was inspired by one I saw on RC Groups. I’ve got 1.5mm and 2mm thick versions. They’re stiffer than the 1mm PepperF1SH frame but I don’t know about durability yet.

More to come when they’re flying..

Micro Quad ESC Frame

In an effort to get content flowing here again posts will probably be higher in image content and short notes rather than long form articles.

As such this is my latest quadcopter build. A micro 1S quad based on the excellent work of http://fishpepper.de.

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I have used the tinyFISH Flight Controller directly so nothing amazing on my part there (thought the FC itself is an amazing accomplishment). My point of difference, and the reason for this post is the ESC frame. I have created a new board layout which uses the schematic of the tinyPEPPER 4-in-1 ESC but laid out on a PCB that serves double duty as the frame for building the copter on to.

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My initial motivation for this creation was to avoid the wait time of a custom carbon frame being cut. With the time spent on this layout and delays in production I could of just as quickly gone down the more traditional route but this was a fun project and I picked up some new skills. With the tiny size of this copter the frame fits within the common 100×100 size limit of cheap PCB fab houses. I used JLC PCB as a test this time around and for $20 I got 10 PCB’s with 2oz copper. Unfortunately the delivered spec. was not what I was after. The board is 1.6mm rather than 1mm (so much extra weight!) and the solder mask could only be green, the sticking point being the 2oz copper.

In any case it flies as is, there were no problems electrically with the PCB. Assembling the tiny components was challenging my first time around but became easy enough even though I’m only using a soldering iron, hot air rework station and wire solder.

As required by the terms of the CERN open hardware license v1.2 my source files (KiCad) are available under the CERN open hardware license v1.2. Feel free to use the design – but make sure to give proper credit and release all modifications under the same license!

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ESC_Frame by aTaylor60

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I modelled a new mount for the FPV camera which better suits FDM printing (no support required) and puts the lens on the centre line. There is also a bit more space withing it as I was finding the fishPEPPER designed option just wasn’t fitting the camera I had. A small dab of hot glue in the bottom of the mount ensures the camera stays put. It is available on Thingiverse.

thing_icon_57CM275t mount by ataylor60

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To simplify the routing for the PCB fabrication I mount the battery with a rubber band that loops around the standoffs for the flight control stack.

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I already have parts and plans for another 2 builds. One will be with this same ESC Frame but using 10000kV motors and another will be using the recommended 8000kV motors on a carbon frame (either my own design or the PepperF1SH design). I’d also like to get another run of boards from a different fab house in 1mm thickness and build a 2S version but that is a little further down the track.

I’ve also got a number of other custom designed but larger scale copters that will eventually find there way onto these pages. So many projects, such little time!

215 Hopper FPV Rebuild

I finally have the design of the 215 Hopper at a point where I think it is fit for purpose as an FPV copter. It can now sustain a heavy grounding without terminal damage. I still won’t claim that it is as durable as a carbon plate design but I am now happy to release it. The camera pod is perhaps the least durable part of the design however I am still flying with the first one I printed and it has served its purpose protecting the flight cam. I do intend to upgrade it at some point but that will probably come after the custom camera pod for my Shendrones Tweaker.

If you’re interested in building a 225 Hopper FPV then you can find all the files you will need over at Thingiverse


215 Hopper FPV
by ataylor60

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I have made 2 changes to the previously seen FPV design iteration to realise these durability improvements. Firstly I scrapped the idea of running the motor wires through the arm tubes. Whilst I think this still has merit, for now it was causing more problems than it was solving. I will perhaps look at it again in the future. I have however maintained a similar motor mounting arrangement. All 4 M2 threads are used to attach the motor to the top half of the motor mount with the motor wires aligned with the arms. Separate bolts are used to clamp the motor mount to the arm tubes.

The second change is specifically to do with the clamping bolts on the motor mounts. Now rather than simply clamping on to the tube end and relying on friction to keep it in place I have created a positive interaction between tube and mount.

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As seen in this exploded view of the motor mount the tubes are now drilled with a 5mm hole to accept the same 15mm M3 standoff that is used throughout the rest of the frame build. The 2 printed parts of the motor mounts then snap over these standoffs and are clamped together with M3x8 button head screws. The only trick to this is that the standoffs must be screwed in to the top half of the mount before the motor is subsequently mounted to that before it is finally installed on the arm.

At the same time as making these motor mount changes I decided to keep things simple and remove the LED tail lights. Now the same 2 parts are used at all 4 corners. Speaking of parts, the image below shows all the parts required to build the 215 Hopper FPV edition.

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Included are (in order from left to right, top to bottom):

  • 2x 215H 101 12mm x 10mm x 183mm Carbon fiber arms
  • 1x 215H 107 Top plate PDB
  • 2x 215H 106 Bottom plate
  • 4x 215H 138 Motor mount bottom
  • 4x 215H 137 Motor mount top
  • 1x 215H 103 Frame side
  • 1x 215H 111 Frame side with USB access
  • 3x 215H 108 Tube clamp
  • 1x 215H 102 Tube clamp with antenna mount
  • 1x 215H 130R Camera pod right side
  • 1x 215H 130L Camera pod left side
  • 1x 215H 126 Video Tx pod
  • 2x 215H 134 Camera pod spacer
  • 1x 215H 132 Camera pod rear post
  • 1x 215H 133 Camera pod front post
  • 1x 215H 131 Camera pod base plate
  • 18x M3x15 Round standoff
  • 2x M3x20 Round standoff
  • 40x M3x8 Button head socket screws
  • 4x M3x10 Nylon screws
  • 8x M3 Nylon nuts

All the 3D printed parts are printed in ABS with a 30% infill, 3 outlines, 3 solid bottom layers and 4 solid top layers. Colour is unimportant but I find it looks its best if the frame parts are a bright colour (as seen here in orange or previously in red) and the accessory parts are black.

The 215 Hopper FPV is designed around a fairly specific set of components. This is not to say that other parts won’t work on the frame but rather that the positions and space allocation work best with what I have used. My recommended build uses:

  • DYS 1806-2300kV motors
  • 18A ZTW 18A Spider series Opto ESC’s
  • Naze32 Rev 6
  • 25mm Plastic housing FPV camera such as the HS117 or HS1189
  • Lumineer TX5G8 Pro power switch vTx
  • FrSky X4R-SB receiver
  • Pololu 5v converter
  • 5cm 90° bulkhead SMA extension

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An important detail to note when assembling the frame is that the flight controller should be in the front half of the craft. The reason for this, as I noted on a previous post, is that the vTx pod must fit around the nylon screws used for mounting the flight controller. There are holes specifically for this purpose in the pod. Another new feature on the vTx pod is the inclusion of the slot seen below. This allows you to see what band and channel is selected on the vTx and also if it is transmitting or not. This small details makes working with this specific transmitter significantly less frustrating.

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A lot of the notes I made regarding the initial build (found here) also apply to putting together this FPV version. In lieu of a full write up for this I will direct you to that if your would like to build one for yourself. Also please feel free to contact me or leave a comment here with any questions that you might have.

There are a couple of build notes that do specifically need to be made for this model:

  1. Whilst not strictly necessary I solvent welded the 3 parts of the camera mount together (parts 131, 132 and 133). Durability has exceeded my expectations so that is probably a worthwhile step to take.
  2. As I have left over PCB’s from my first batch I have not modified the bottom board to include a hole for passing the vTx wiring. You will need to drill this just in front of where it will connect to the vTx. It should end up just inside the ‘mouth’ of the pod.
  3. As the motors are now fixed to the tubes drilling the holes through which the mounts pass is critical. They must be aligned end to end. For this I have included part 215H 139 which is a drilling jig. Print two and slide one on to either end of the arm tube. You can then use the flat sides for alignment. I suggest holding the jig with a clamp or vice whilst drilling as the thin wall carbon has a tendency to grab onto the drill bit.

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If you decide to build one i would love to see it! let me know about it here or post it up as a build on thingiverse.

215 Hopper FPV Durability

As flight hours on my 215 Hopper FPV platform increase it has become clear that the durability of the design is somewhat limited compared to the more common carbon plate design. The core problem however is not breaking parts, though this has happened, but rather pulling wires out of the motors. When the quad comes down it frequently pulls the motor mount from the end of the tube and as the propellor is often still spinning at a high rate the inertia of that then stopping is enough to pull the now loose motor off its own wires. Part of the philosophy with this design was that the motor could be allowed to rotate on the tube in the event of contact and through most all of my LOS flying this was valid and workable. It has now become evident that the sort of crashes I am experiencing whilst learning FPV flying are too much for this design.

With my first iteration of the FPV version another flaw with the rotating tube fairly quickly became evident. The edge of the hole in the centre of the arm tubes was cutting the insulation of the motor wires. In fact this become bad enough before I realised it was happening that the motor wires began to short through the carbon ultimately resulting in the quad falling from the sky (perhaps about 10m). This was the most significant crash to date resulting in a broken arm and several broken plastic parts as well as the previously mentioned motor pulled from wires problem.

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Something odd has also happened to the electronics meaning that 3 out of the 4 motors will not spin up to full power. This problem remains undiagnosed so I have shifted the FPV gear across to my other airframe. In the first image below the spilt insulation is very evident though I don’t think the wires actually shorted at this end, the crack in the tube can also be seen though it was significantly worse when removed from the plastic support.

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In this image, at the other end, the split insulation is also evident but if examined more closely there is evidence of burning from the short on both the tube and insulation of the middle wire.

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Two decisions have come from this. Firstly I have iterated on the design again with a number of changes which I will detail in a subsequent post. Secondly I am building a more traditional carbon plate design which should hopefully allow for a much better flying to fixing ratio upon which I can develop my skills. Specifically this will be the Shendrones Tweaker and as is my way that won’t be a standard build so there will be a post about that soon too.

215 Hopper FPV Airborne

Over the weekend just past I got my first solid session flying FPV under my belt. This of course means, as the title of this post also states, that my FPV build of my 215 Hopper design is complete.

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The build wasn’t quite as smooth as I had hoped for a few of reasons:

  1. The new routing for the motor wires, through the arms, came up short. An extra 10mm or so and I would have run them as they were. As it is though I ended up extending the wires. This also made soldering them to the ESC’s a simpler task so it was a good move in the end. Despite the extra complexity in the build I am very pleased with how this aspect of the design turned out.
  2. My initial design for the base plate of the camera mount fouled on the zip ties that hold the ESC’s in place. I had to shorten that and print the new design.
  3. My initial design for the video transmitter carrier fouled on the heads of the screws  that mount the flight controller. This was actually 2 errors rolled into one. I absentmindedly assembled the frame back to front with respect to the flight controller. i.e. the flight controller is in the front half rather than the rear half. This doesnt make any difference flight wise but it would have meant the carrier wouldn’t have fitted up even if I had accounted for the flight controller screws.

The second failure with the video transmitter carrier design is also the same failure as with the camera mount. It is a lesson that I have learnt the hard way on to many occasions and it is thus; If you are using CAD use it fully, every detail should be represented in your model. If you leave something out, either intentionally or inadvertently it will come back to bite you at a later stage of the project. In the case of the camera mount I didn’t even have the holes for the zip ties let alone the zip ties themselves. For the transmitter carrier I didn’t have the screws in my model. Thankfully having the 3D printer on hand meant that I could correct these errors in the space of an evening and was ready to fly on saturday morning.

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With the new build came new batteries, I am now flying on 4S 1400mAh batteries (hobbyking) and loving it. I went with the higher discharge rate option, it is perhaps overkill but it means I get much further through the capacity of the battery before voltage sag starts hitting my warning levels.

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Other than the mentioned hiccups the build was much the same as the ‘base model’ 215 Hopper as I detailed here. I will put together a similar writeup for the FPV model in the near future. The design files will also be available. On top of that I now have a big stack of PCB’s for the build which I will make available for purchase. A full frame kit with hardware and 3D printed parts may also be an option.