RCU Forums - First carbon fiber 3D printed component: Diamond gear doors.

This is another World first from Ultimate Jets.
The first commercial application of 3D carbon fiber printed components.

This is a super high tech application that is going to be available very soon to our customers.
The parts is made from my highly modified Stratasys printer, using NEFCAR. The component is a very unique thermo-activated nano carbon fiber charged NOVALAC epoxy resin.

http://www.rcuniverse.com/forum/rc-j...-material.html

Here are a few pictures describing the process:

1. The parts are CAD designed. This is a very long and precise step as I integrate the hinge recess, reinforcements and control horn from the CAD stage ( to minimize the setup work for the customer).

Note on this screen capture of the main door that the strut and rotation pins recess are integrated in the design.

https://fbcdn-sphotos-e-a.akamaihd.n...08621357_o.jpg

2. The part is 3D printed.
A specific algorythm is used to create 3D honeycomb filling of the parts. The upper and lower skin are composed of 4 very thin 0.15 mm layers of material printed at different angles to improve stiffness.
The following picture shows the first two layers at 45 degrees that are designed to give torsional rigidity. Note that the carbon fiber structure that aligns with the print head is clearly visible here.

https://scontent-b-ams.xx.fbcdn.net/...18&oe=54D7F778

Here is another picture of the 3D honeycomb filling being printed.

https://scontent-a-ams.xx.fbcdn.net/...c4&oe=550D571C

Here is a small diagram of what 3D honeycomb looks like:

https://scontent-b-ams.xx.fbcdn.net/...be&oe=54D595D8

The honeyconmb structure is visible vertically ( octogonal ) but also laterally ( pentagonal ) in two directions. On the gear door, the lateral pattern is used from top down.

Here is the nose gear door before fitting:

https://fbcdn-sphotos-d-a.akamaihd.n...18506647_o.jpg

Note the following on this door:

. Internal 3D honeycomb structure
. Ellipsoidal cavities
. 45 degrees chamfers
. Integrates control horn
. Crazy light weight ( less than 20 grs ) and super high stiffness.

Here is the main gear secondary door:

https://fbcdn-sphotos-d-a.akamaihd.n...7fb84469bf74b1

. Internal 3D honeycomb structure
. Hinge recess
. 45 degrees chamfers
. Integrates control horn
. Crazy light weight as well ( less than 15 grs ).

The top layers on all doors are very thin at 150 microns each ( 300 microns total thickness ) but add a tremendous amount of rigidity to the doors.

3. The kit comes with all the doors, PYCABS printed door brackets ( for shock resistance ), 3 JR 3421 servos, 6 ball hinges and threaded rods, screws and hardware and a set of very precise instructions, minimizing the assembly time. Everything is laid down: from servo position, ball link position on the servo arm to gluing techniques and programming.

Here are the doors fitted on the plane:

https://fbcdn-sphotos-b-a.akamaihd.n...97716354_o.jpg

The door servo fits perfectly in the gear bay, just besides the wheel. It is fixed with my PYCABS Ultimate Servo Brackets:

https://scontent-a-ams.xx.fbcdn.net/...ef&oe=55168FED