Antonov An-22 (or Tupolev Tu-95) NK-12 Model Propellers by Classicaviator

Last crawled date: 3 years ago

25-Jan-2017 update: I took down the video of the props working due to another issue I had with Youtube. Sorry about that, but the video is no longer available.
28-Jan-2014 update: The thing is finished and tested. Two more changes made to the cooling spacer and the rearward spacer. Watch video of the test run (pardon the crude setup - just using the tools available at hand) - http://youtu.be/tcZVFtfykug
24-Jan-2015 update: After printing all of the components and mounting them on the motor, I've discovered a few more issues with spacing and bolting. I've updated all of the parts and re-uploaded all of them. Also uploaded assembly progression steps.
21-Jan-2015 update: Fixed blade misalignment issue. Also increased forward prop hub clearance on Prop_2. Best when printed at 0.1mm Z resolution. Updated STLs: Prop_1.stl, Prop_2.stl.
I sketched these in SolidWorks to fit my Antonov AN-22 1/40 scale RC model I am in the process of building. They fit the scale almost perfectly, and work well with the CR23S 1700KV contra-rotating electric motor (http://hobbyking.com/hobbyking/store/__17150__CR23S_Contra_Rotating_BL_System_1700kv_.html).
I haven't tested it yet, but have printed some of the parts, including the #1 prop (the front). The parts were sketched with FDM printing process in mind and are all printable with single extruder and no supports. However, lower resolution is recommended for the prop blades. Works especially well with ProtoPasta's new carbon PLA filament! http://www.proto-pasta.com/shop/cfpla
The blade angles are set for 45 mph maximum theoretical flight at 9600 RPM, which really means nice slow 25-30 MPH flight at mid power.
Feel free to shoot any questions my way, as well as any needed mods to the design.
Note: if you plan on using these on a real model, please consider testing these parts first in a safe environment before flying your model. I am using pretty strong materials on my end and feel they are safe, but I cannot guarantee that all filaments and materials have the same strength (they don't!). Also, sanding and bondo filling is not only recommended, it's necessary for good smooth working propellers. And, most importantly, don't forget to balance the props before they go on the motor!