ARX-R V2: This One Hits the Mark

By QuadStar Drones on May 27, 2019

26  423  5

Alt Tag

This Beast Hits the Mark

Unlike my first V2 build, I'll elaborate on this one a little more.
After a long year of refining this frame style, the V2 finally takes care of the last 2 design issues: crash-ability and quick repairs.

The Feedback
I haven't had much time with this frame (I still have to try some speed runs!), but given the feedback that I've been getting, expectations were exceeded :) Effing fast, effing quick, and effing smooth were most descriptions I got from people. Best of all, the frame has proven to be very resilient in crashes - there weren't very many reports of broken arms. In most cases, it was due to a collision with concrete or a light pole.

Crash-Ability Improved by "Adaptive Flexibility"
The adaptive flexibility of the frame has worked extremely well. How does it work? It works by allowing to let the frame parts move during hard impacts. It is engineered in a way that maintains a very rigid structure while flying, no matter how hard you fly. If you don't believe me, take a look at the plasma tree noise plot below. During a crash, the arms and center plates are interlinked in a way that allows impact energy to be absorbed and dissipated throughout the frame to avoid breaking arms, etc.

When It Does Break, How Does the Quick Repair Work?
The arm spars have a unique way of being "hooked" into the centerplate. Once hooked in, the other end of the spar is swung into place underneath the motor (creating some tension) and is kept in place by clamping it down with the motor mount. Other than removing the tape/zip ties holding the motor wires onto the spar (unless it's the spar without motor wires attached to it), you only need to remove one motor screw (per spar) to replace it and takes around 1 minute. Not to mention, the spars are cheap and also thin enough to ship cheap in a letter sized envelope.

Features of the Frame

  • Save some money: Canopy, battery plate, and accessory plate stl files are available on thingiverse (canopies, etc are also available for purchase if you don't have a printer):
  • Efficiency: the low profile 2mm spars allows for unmatched acceleration, speed, and longer flight times.
  • No screws: Only the motor screws are required. However, it isn’t a house of cards – the frame won’t fall apart if you remove a motor.
  • Smooth flying: The low profile arms are less affected by pressure vibration from the props.
  • Easy layout change: Both 5” and 6” arms use the same center plates so you can switch between 5”/6”/Hybrid
  • Flip open canopy: This is a suggested way to set up your build. The front o-ring is zip tied and the back o-rings are left unzipped. To access the stack, you only need to unhook the back o-rings.
  • A TPU accessory plate now comes with the kit. The plate goes on the top of the stack and can be used to zip tie those awkward items such as vtx and rx.
  • "Adaptive Flexibility": improves crash-ability by allowing the frame to flex under hard impact forces.
  • When the arms do break, the spars can be changed in about 1 minute.
  • 57g for a 5" frame doesn't sound that great until you consider that includes the motor screws, stack hardware, battery straps, and canopy. The 6" frame only adds another 2g. This particular build isn't all that light mostly due to the motors. However, I have another build that comes in at 208g with everything but the battery.

In Summary

It's Everything a Race Frame Should Be

  • Quick and simple assembly
  • Quick repairs
  • Quick access to the stack
  • Lightweight
  • Unmatched acceleration and speed

The Future

Right now, there isn't anything I would change and I'm sure any changes that are made will be very minor.

Top Speed Version
I keep saying I'm going to do this. The problem is making it work without making it too complicated. I may just break it down into 2 types of speed versions:

  • A more "basic" speed version in which the frame can be laid out like the vertical layout of the ARX-R V1
  • An advanced version in which the layout is (again) much like the vertical layout of the ARX-R V1, but with a complete shell which will require a bit more time to build and limit the size of the electronics.

Going Thinner?
I had a maiden flight today of a 1.5mm spar version of the frame and it was as smooth as butter. I will plan to make 1.5mm spars available for those that want to shave off a few more grams, increase acceleration and increase top speed. However, I think 2mm is the best all around choice.



Sign in to comment

HK-AERIAL VTOL   21 days ago  

I admit I can be a simpleton at times. When I ordered my first (6") ARX I thought: "well I'm using a 20mm stack... I need the 20mm canopy". When I saw this build I looked at my 5"'s canopy (the new 30mm) and realized it was much bigger than the first, and so I swapped it. I could get the 20mm canopy to work for me, but the extra room has made all the difference to my build.

MANI FPV   22 days ago  

Awesomeness! Three of those drones sitting together is sick! Beautiful builds. I'll mail you an order for 12pcs of those 1.5mm arms.

HK-AERIAL VTOL   23 days ago  

OMG! It's beautiful!

StickyRice   23 days ago  

i thought it was a whoop lmaooo

ThumbzFPV   23 days ago  

I'm so stoked you've got the frame to it's final iteration! As a race rig nothing has served me so well. Thanks for all the time and effor you've put into this.

Guides & Reviews

26 2,343  26
20 days ago

A couple years ago I built the TransTEC Frog and since then I've been patiently waiting for another TransTEC frame to catch my eye. Fast forward to today and the TransTEC Laser S is that frame. It's a 82g racing frame that features 6mm arms, a TPU micro cam mount, 30.5mm and 20mm stack mounts and 3K carbon and 7075 hardware. My goal here was to build a high quality 6S racer at a reasonable price. I'd..

Read more
61 8,392  94
Apr 17, 2019

Wizard Killer X220HV Mark IV - 6S Freestyle on a Budget

Read more