- Joined
- Feb 26, 2015
- Messages
- 44
- Reaction score
- 13
- Age
- 54
I bought a set of these direct from Tmotor as I'm based in the UK, but the hubs don't fit my I2. They look the same from your photos but the centre hub is a few millimetres to small to fit on I2. Waiting to hear back from Tmotor to why mine seem to be different. Pretty gutted as had the heliengadin folding props, but was really disappointed with the quality of the props so gone back to using non folding Tmotor 15" props with heliengadin adapters, but they are a pain to take on and off all the time
Helinengadin folding props
I have not experienced any wear issue although I do agree a bushing would have been nice. I have always kept my props tight enough that on startup and shutdown they stay pretty straight. If I straighten them on startup I see very little vibration if any. Its seems if I tighten them just to the point of trying to push the prop with my finger they have a little stutter to them , and if you push them and they have a fluid smooth motion they are to loose and will fold some on shutdown along with a noticeable vibration on startup. Thats what works for me. I originally thought about using blue locktight on the hub screws but never did , have never noticed any issue of the screws loosening but still ck them regularly . I see these new T-Motor props use a shorter screw since they mount lower in the hub . Dont know if that will make any difference in the screw loosening without locktight.
These new T-Motor props do look sweet and think Im going to give them a try for that factor and not having to remove the hubs to adjust the prop tension is a very nice feature
The hubs also look like they have a much lighter design, they rotated the mounting hub screws which help enabled a smaller hub design, less rotating mass cant hurt either. Plus the aerodynamics of button heads versus nuts on the top side. lol
I can see a lot of marketing pitch here, but wiglet design would only be beneficial for traditional forward mounted propeller on aircraft. That is because of distribution of airflow on rotorcraft is completely different from what you have depicted.That's why you never see it on production rotorcaft, wiglets induce additional horizontal drag and actually reduce efficiency of propeller on rotorcraft.
Reference to Aerodynamics for Naval Aviators by Harry Hurt, also to
Abstract from "Aerodynamic impact of a streamwise vortex on a propeller" Y.Yang L.L.M.Veldhuis G.Eitelberg Aerospace Science and Technology, November 2017
"To study the impact of the vortex on the propeller, the Batchelor vortex is utilised to model the impinging vortex, and its effect on the propeller is calculated by Computational Fluid Dynamics. The loading on the propeller increases due to the impingement of a contra-rotating vortex, and the opposite is true for a co-rotating vortex. However, the torque coefficient of the propeller changes consistently with the thrust coefficient which leads to the efficiency of the propeller being independent of the impinging vortex. With the vortex impinging on the propeller, a strong pressure fluctuation on the blade is observed, especially on the leading edge of the blade."
edit for vendor post
Certainly propellers for DJI Inspire 2 are being sold with perfect knowledge of what determines the speed of rotorcraft.
Whole thing sounds a bit amateurish (no disrespect).
Maximum speed depends on forward inclination angle and engine thrust (not RPM, voltage or GPS) that is programmed in firmware (and can be changed in developer mode).
It is possible to measure thrust with new design on a bench. If thrust increased notably vs. stock it may prove more or less scientifically benefit of installing them on the craft.
Speed is limited to improve gimbal stability and to reduce vibration.
Inspire 2 can easily go initially advertised 67mph @ 42 degrees inclination, and closer to 80mph @ 50 degrees (not safe for obstacle avoidance).
Can you adjust the tension of the props without removing hubs from the motor (is there a nut on the bottom side or are the hubs threaded ? ) as I see the button allen head is on top versus on the bottom with the Helinengadin folding props ( with nuts on top and will spin without holding with a allen you cannot get to without removing the hubs ) Have been using the Helinengadin folding props since they came out and love them except for that. As for me I applied direct heat from the end of a soldering iron directly to each bolt before attempting to remove the stock hubs ,I believe this is a must when removing along with using a correct ground hardened tip torx if you want to avoid stripping out a screw and a lot of frustration that will come with that. Also work the screw back and forth as you are removing worked well for me.
I have folding props on my regular RC helicopter. What I notice is the hard shock they have when rotoring up against the hub along with the shake until they get up to speed. Given the I2 motor mount seems the weak link, I wonder if the carbon fiber jar on starting might affect that joint?
We use essential cookies to make this site work, and optional cookies to enhance your experience.