Hi
I have searched through the discussions in this forum and Googled for this question but could not find the answer.
I am planning to mount this motor ...
on to aluminum frame arm. It is a 15mm square arm.
What re the pros and cons of mounting it directly to the frame with 2 screws, like this one
compared to mounting it with the special "mount plate" like this one and 4 screws?
Replies
If you balance your motor and prop as a single part, to minimize vibrations, that is the best you can hope for with a rigid mounting scheme. I have never balanced any motors or props and my machines fly and fly well. (Gasp!)
Countless words have been written and debated here about vibration mitigation and reduction.
In simple terms, do your best and then move on with the project. There is far more work in learning to fly and operate the aircraft.
I would recommend installing a motor on an arm -- any way you choose -- and then spinning the motor up with an ESC and servo tester. With the arm mounted or clamped to a bench, you can get a feel for the motor imbalance. Add the propeller -- TAKE CARE OF THE BLADES -- and check that for vibration. If at any time you have a serious vibration issue, find the problem before proceeding to mounting on the airframe.
This will be good only for the mounting on the bench. Once your arm is on the airframe and all the other arms are added, the model now becomes very complex. In sync, partial sync, counter poised off balances all come into play and you can drive yourself crazy thinking about them.
Again, this takes away time for flying and more productive efforts on the project.
Good news on the laser cutter. I am building a new CNC router for flying machine parts myself. The small one in the DIYD blog linked was a starter machine. The new machine is a MOMUS V2.
-=Doug
Plates add more parts and weight. -CON
Plates allow simpler repairs and flexibility for change - PRO
Direct arm mounting requires more machine work - CON
Direct arm mounting reduces parts count and weight - PRO
Take a look at my Instructable for my last direct arm mounting style.
My first build also used direct mounting but was a little less refined than the Instructables build.
Good luck and feel free to reach out for more help.
-=Doug