Pro Tricopter Delrin Kit v1.2

The world’s most popular tricopter kit features motor mounting options (up or down), mounting support for most motors, folding booms, and ZeroYawSlop

Build Manual | View build log by David Windestål at RCExpolorer

Price (w/o Arms): $94.99USD buy at: GetFPV | ReadyMadeRC

We now offer fully built, ready to fly tricopter kits.

Foldable frame design fits in a back-pack

Kit Version v1.2 Updates (as of April 2012)

  • We updated the servo bracket to accomodate Hitec micro servos like the HS-85MG (metal gears). Hitec servos generally are much easier go get around the world than the previous BlueBird servo. Hitec makes a variety of micro servos and they all have slightly different sizes, so some minor sand papering may still be required to make your servo fit.
  • We switched the ball links for the push rod assembly to high quality DuBro ball links. The resulting push-rod is stronger and provides for even less slop.
  • New stainless steel yaw axle. The previous axle was made of aluminum. It was very light but a little too flexible. The new stainless steel axle is custom machined for us to our exact specifications. It is much harder and stiffer than the previous axle.
  • New bamboo camera plate and lower Delrin frame plate. We removed 4 of the previous 8 connection points between the Delrin and the bamboo plate. The remaining 4 connection points have been beefed up to accomodate our soon to be released vibration bobbins. The new plates also allow you to drill the holes to 4mm, which makes sourcing vibration bobbins a bit easier in case you want to upgrade.

Featured Videos

Kevinv033 taking his Pro Tricopter build for a spin

Kit Version v1.1 Updates

  • Mount any Motor! — New motor mounts that mount most motors including regular out-runners with 16mmx19mm mounting holes, HK NX-4000 series, DT-750, and AX-2213N.
  • With the ability to mount motors such as the NX-4008 comes the ability to fly with 4s Lipos and gain additional power and substantial flight times (20+ minutes with a 3300mAh)
  • KK Board Now Fits By Default — Hardware package now includes 4 additional 10mm male/female spacers which you can use to increase the clearance between the frame and the flight controller cover — this allows easy mounting of the HobbyKing Quadcopter KK board.
  • Stronger servo mounting bracket.
  • Nylon screws for the back arm have been replaced with steel screws to add strength.
  • Improved Hardware — We improved the hardware and are now including lock-nuts for the frame steel screws. The needed allen wrench for the axle collars is now also included.
  • We are now only making the black kit and have retired the white kit.

More Info…

Record super smooth HD footage with optional padding

Long flight times — 28:30 minutes with NX-4008 motors, 10×4.7 props, and 6600mah 4s Lipos

more videos

Pictures

Build example: props pointing down, 14" booms

Kit includes over 160 frame and hardware parts

Materials: Delrin, Acrylic, and Bamboo

Foldable frame design fits in a back-pack

All Up Weight w/o battery: 630g

Mounting support for most motors

More Photos of the Black Kit

Featuring the “ZeroYawSlop” Yaw assembly

The Yaw assembly is the most complex part in any tricopter. Our kit’s Yaw assembly uses precision ball-bearings and a custom manufactured, stainless steel axle. In combination, this assembly provides ZeroYawSlop and spins freely and easily. The video below shows that just blowing on the motor mount makes the motor mount spin for a long while. The assembly is sturdy and extremely precise. The kit comes with 2 ball-links and a 1″ 2-56 threaded rod to create a slop free push-rod from your servo arm to the control horn of the Yaw assembly.

Specifications and Kit Features

  • The kit can be assembled with the motors pointing up (regular) or down, for “zero prop-wash” effect. Your choice!
  • Front arms can be folded back for transport/storage and can be secured with a screw and nut, if required for acrobatic flying
  • Frame parts made from precision laser cut Delrin: 3 Motor mounts, complete Yaw mechanism, 2 main body frame parts
  • 1 Camera mount for GoPro and/or flight cam. Made of vibration slowing bamboo.
  • 3 feet made of clear acrylic
  • 1 flight controller cover made of fluro acrylic that protects your flight controller in case of an upside down crash. Now fits the KK Board via included 10mm stand off extensions.
  • Weight: Fully flight ready built kit with all electronics, flight controller, motors, escs (without battery) weighs 630g.  Kit frame and motor mounts: 150g, kit hardware: 50g.  Total kit weight: 200g. More on kit weight and thrust.
  • The Yaw mechanism uses precision ball-bearings that are pressed into the Delrin, requiring no glue. The axle for the Yaw mechanism is made of stiff stainless steel. The assembly provides for ZeroYawSlop. The kit also comes with ball links and threaded rod to create a slop free push-rod to connect the servo arm to the Yaw control horn.
  • Includes all frame and motor mounting hardware: screws, nuts, ball bearings, servo to motor pushrod using ball links, Yaw axle, and stand-offs
  • Includes a jig to help you with preparing your arms and where to drill the pivot holes
  • The kit does not include arms giving you the choice of arm material and arm length and also lowers your shipping cost. You can use cheap and easily replaced 10mm wood squares or aluminum, carbon fiber, etc.  Make it to your own preference. Users have built the kit with 3/8″ wood arms which are easier to source in the US (which are 9.5mm).
  • If you purchase HK 800kv motors or HK DT-750 motors, you will not require to drill any holes or think about getting the correct hardware. 2mm screws and nuts to mount all motors are included. The kit also supports out-runners with 16mmx19mm mounting holes (But needed M3 screws and spacers not included in the kit).

Flexibility

The kit provides you complete flexibility on how you assemble your Tricopter. All the hard parts are done. Build examples below.

Only 2 examples.Slow Flyer for FPVAcrobatic Flyer
Arm length (measuring just the wood)15" to 17"7" to 13"
Prop Size10x4.5 or 10x4.710x4.5 or 10x4.7
Motor MountingFacing UPFacing DOWN
FPV GearVideo TX, Flight Cam, OSD, etc.None
HD CameraGoProNone
RC RXEzUHF or other LRS2.4GHz
All-Up-Weight (AUW)>1KG<1KG
MotorsNX-4008 620kvAX-2213N 800kv
or
DT-750 750kv
ESCPlush 18APlush 18A
Lipo3300mah to 5000mah 4s2200mah 3s
Total Thrust1129g x 3 = 3387g690g x 3 = 2070g (AX-2213N)
~850g x 3 = 2550g (DT-750)

Accessories

We offer a number of different accessories. Find the accessories in the GetFPV store’s tricopter category.

  • The Y6 conversion kit that enables you to convert from a tricopter to a Y6 copter.  This kit consists of an extra motor mount that you use instead of the Yaw mechanism. It comes with two motor mount Delrin plates, nylon spacers, nylon and metal screws and nuts.
  • GoPro vibration pad/mount that helps reduce vibrations to the video picture.
  • Out-runner motor mounting hardware that includes 3M screws and spacers to mount any out-runner with 16mmx19mm mounting holes (on kit v1.1 and up)
  • Crash replacement hardware
  • Various crash replacement frame parts

Why Delrin?

I always get suspicious when I read marketing language for new plane or mutlicopter kits that tout “crash proof” or “indestructible”.  Nothing in this world is indestructible.  I want to give you some background for why I chose Delrin as the material for this kit.  Good context for why Delrin is a great fit for this tricopter frame is to look at something else that is made from Delrin: Guitar Picks.  Guitar Picks are thin pieces of Delrin that are hit against metal strings for hours on end, with force and without breaking.

Delrin is an extremely strong plastic of high quality. It is softer than fiberglass board, which is the main reason it holds up so well in crashes. Rather than breaking, it will give in a hard crash — just like a guitar pick that gives rather than break when slammed into metal strings. Only when I crashed our prototype into a granite park bench at full speed, which caused a sound as if that was my last flight with this Tri, a small piece of the servo mount cracked which was easily fixed. Delrin is not indestructible, but super super strong.  It always amazes me how much abuse it can take.  I crashed our prototype over 20 times, but the servo mount crack I described is the only  damage (so far).  After my encounter with the park bench which was a real crash that would have totaled any heli or plane, I pushed the arms back out, put a piece of tape on the cracked servo mount and was flying again.

For FPV, Delrin is a better choice over carbon-fiber as it does not interfere with your video signal, which carbon-fiber can. The FPV Zephyr wing or FPV EasyStar use fiberglass spars and not carbon-fiber spars for that same reason.  Delrin is also a lot less expensive to source compared to carbon-fiber, which is the  reason for the low price point of our kit.

Wood Booms/Arms and which wood to choose

First time tricopter builders will try to find the most technically advanced material that “looks the best” to make their booms. Carbon, aluminum, fiberglass are all options. Many commercial tricopter kits that do come with arms (ours does not!) come with either carbon fiber or aluminum booms. However, builders that have gone through a few tricopters in their time often realize that wood is one of the best boom choices. One of the key design principles of a tricopter (or any multi copter) is to prevent the flight controller board, and specifically the gyros located on that board to be exposed to the motor and prop vibrations that are traveling from the motors, through the booms, to the flight controller. No material does a better job at slowing down vibrations than wood. While not as strong as carbon or other man made materials, it is surprisingly resilient. It is also easily replaced after a hard crash that does break a boom. Cutting and drilling wood booms only takes a minute.

Lastly, wood is the most affordable boom choice. Even in the US where 10mm wood is hard to come by, you can order 36″ 10mm x 10mm poplar or basswood for $1.30 a piece plus shipping (that’ll make a couple of arms unless you go longer than 18″ per arm). While most RC plane builders will look for basswood as it’s lighter than poplar, I don’t think it matters which you choose for a tricopter boom. Basswood feels a tiny bit more like balsa and poplar feels just a tiny bit harder and smoother. In a 10mm x 10mm boom, I think the flex is about the same, but poplar is stiffer and basswood said to be softer. The weight difference of a 36″ 10mm x 10mm piece is only about 4 grams (basswood being the lighter one), so only about 2 grams per boom or 6 grams total — insignificant for most builds. In terms of sourcing wood locally in the US, you can also go to your local lumber shop/yard and ask them to trimm a 1/2″ pine wood square down to 10mm. Just make sure they don’t give you a 3/8″ piece, which they tell you is the same as 10mm (but it is 9.5mm).

What you’ll need to complete your tricopter

QtyItemSourcePrice Each
3Motors — many choices supported
2213N 800Kv Brushless MotorHobbyKing$9.34
RCHobbyBase.Com$8.90
LowPriceRC.Com$9.65
DT-750 750kv BrushlessHobbyKing$11.60
NX-4008-620kv BrushlessHobbyKing$32.00
GetFPV$36.73
Outrunner with 16x19mm M3 threads like the Tiger Motors MT-2212-16 750KVClubHelis$35.99
3Propellors — for best performance, get 2 CCW (regular) and 1 CW (pusher) props
APC 10x4.7GetFPV$2.93
GWS 10x4.7HobbyKing$1.20
310mm arms (we recommend wood). If you can't find 10mm, many users have used 3/8" (9.5mm) instead and made it work.Hardware Store for wood. In the USA, try Magnum Wood$1.30 for a 36" piece
318A Plush ESCHobbyKing$11.90
GetFPV$16.99
1Flight Controller Board — There are many choices. Below are some examples.
KK Boardkkmulticopter.com$75
HobyKing Quadcopter Board
(get the USB Loader to update the firmware as well)
HobbyKing$15
Multi Wii Copter (with auto level)MultiWiiCopter.com$159
3Prop Mounts or Prop Savers
Prop Savers
Don't get the HobbyKing 10 pack. They don't fit well.
HobbyKing (not confirmed the fit)
-- OR --
TowerHobbies. These are confirmed to fit GWS, Maxx, and APC.
$1.49 - $2.59
HobbyKing Prop Adapter 3mmHobbyKing$1.99
E-Flite Prop Adapter 3mmNo longer recommended!n/a
1Micro Servo: The kit is now better sized to support standard Hitec Micro servos like the HS-85MGHitec$31.00
1+Lipo Batteries — 3s or 4s depending on motor choice
2200-2500mah 3s LipoA good, high C rating battery would be the 2200mah Nano-Tech$23.87
3300mah 4s Lipo (for supported motors)Turnigy 3300mah 30C$29.90
1RC RX of your choice
4Servo extensions (length depends on your arm length). 3 for ESCs, one for Yaw Servo.
Lots!4" Zip TiesHardware Store
9Motor to ESC connectors: 3.5mm gold connectorsHobbyKing$1.59
1-2 meter16 or 18 gauge Silicon Power CableHobbyKing Black
HobbyKing Red
$1.29
Strong velcro and velcro strip for battery, double sided tape for flight controller.

Build Manual

The build manual