Hi all have a small glitch :-(
I have 4 x emax 2213 motors with the keyed prop mounts
so how do i turn the props upside down to do the compass mot ?
Or do i just bolt the frame to the ground and do the compass mot
with the props the correct way up ? (just seems a little unsafe)
sorry if its a daft question
Replies
In testing a heavy lift hex I was very uncertain about ANY sort of tethering, and then read about moving the props one position CW or CCW.
Now this thing is scary at full throttle but setup like this is no problem, as long as the legs can stand up to the load, as it is pushing itself down onto the floor.
MUCH safer than trying to restrain a ballistic missile.
I had my twin boy teenagers hold the hexa down while I did the procedure. They were not real eager, but dammit, Science!
It was most impressive. In my small den I spun the thing up and as it tried to launch itself through the ceiling my boys bravely held on. Got up to about 80% throttle and dustbunnies started flying about, papers flew off the desk. The cat bolted. I felt like Dorothy in the tornado until I finally ran out of courage and chopped the throttle.
Very exciting, but in retrospect I think it might be a good idea to attach the thing to some Immovable Object instead of risking ones (suspect?) gene pool.
You don't have to reverse the props, just move them around one position.
As each motor turns opposite that means the copter is pushing down not up.
Turning them upside down does not do this.
I had a similar problem with my hex and decided to leave the props and tie the beast down. There are a lot of ways to do that. A suggestion is to use a piece of plywood as a base and install four eye-bolts on it. Then use a single length of stout cord looped around each arm of the quad and tied off with no slack. Finally (and importantly) weigh the plywood down with a couple of bricks or such.
Or, Lacking eye-bolts, drill holes through the plywood and feed the cord through them,
Or you might look at the spare tire in your car - if your quad will sit on it nicely all you might need is a length of cord fed through the bolt-holes.
To be safe: use stout cord in a long single length wrapped around arms (not landing gear or other appendages), solid anchors in base, no slack, good knot, plenty of weight.
This sort of lash-up can be handy for all sorts of bench-testing, Obviously you want to stay well clear of the props.