SKEW_R

Development of the SKEW_R started in the depths of winter when I decided I'd try racing again in the coming season. At the time my race builds were a pair of Mahou Shoujos (what would eventually evolve into the Morningstar). I wanted something a bit lighter and easier to work on though - whilst very hard to damage, the HDPE quads were tough to quickly fix if anything did go wrong.

As a result, I designed a carbon stretch plus with near identical geometry to the Mahou Shoujo. The main visual oddity was that to maximise the hole spacing for the two arm fastening screws, I ended up making the frame asymmetric to make use of the stack and pod screw holes and minimise component count.

The resulting frame was light, but did have a few drawbacks. Access to the front pod screw was difficult when disassembled and impossible with a camera installed. Putting the pod mounting holes at offset by 45 degrees to the stack holes seriously restricted the size of 4-in-1 ESC boards that could fit. The slots for the battery strap were too close together, which led to a lot of movement and potentially cuts to the strap.

Despite the flaws, I went ahead with test flying and though it flew nicely, it proved to be too weak in reality. The cross braces snapped easily, one arm broke at the body, and the final nail in the coffin was when a motor came off in midair and destroyed itself, and a second motor died in the resulting crash. After this, I shelved the project and instead went back to developing the Mahou Shoujo, which became the Morningstar and my primary race quad for the first half of the season.

By the half way point of the racing season, I found myself wanting to make the jump to 6S. My 4S equipped Morningstar builds had the speed to compete, but especially for events in Scotland (which had much longer rounds than English races) I was suffering from massive battery sag at the end of each round. When I realised I could get cheap 6S LiPos from Hobbyking, I decided to make the switch, and whilst I was at it, come up with a new quad design too.

So once more I found myself looking at the SKEW_R. It had potential...just not as it was. As such, I redesigned the whole thing from the ground up, taking the good parts and replacing the bad. The arms were still asymmetric but the pod holes moved to the corners of the stack instead of the middle. It kept the crossbraces (now 4mm rather than 2.5mm carbon), but the motors moved to a 4 screw mount with separate motor protector pieces rather than having them stick off the end of the crossbrace. The new shape meant a battery strap could run the full width of the baseplate under the ESC board, and a 3D printed spacer protected it from the sharp carbon edge. The end result was a much easier to build, stronger frame - whilst technically a Mk2, the new frame took the name of the original, simply being called the SKEW_R.

The initial testing went well, and as a result I built another pair of prototypes to run for the rest of the racing season, culminating in qualification for the British Championship, showing that they (and the Morningstar) are capable race day machines.

The SKEW_R frame is available to order here.

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