How to mount my props?

[Budge]

I'm a newb and building my first tricopter. I don't have any wooden washers like David uses in his scratch builds. So what's the best way to mount my props? I've tried mounting them in this order...locknut/washer/prop/washer/locknut...but that leaves a gap in the shaft between the bell and the prop that makes me worry about bending the shaft. Is one washer and one locknut on top of the prop enough?

 

[xuzme720]

Yes, the gap isn't ideal but it's better than loading the bearings by going too tightly against the bell and side loading the grub screw. If it seems to be more of a concern to you, you could make up the gap with washers. Just make sure you aren't tightening too much against the bell. Keep in mind though, if you are mounting the motors with zip ties, those will likely break away before the shaft bends.

 

[Budge]

Thanks xuzme720.

 

[colorex]

Originally David mounted his props directly on the bell. But I found that it is not good for the motor to do this, I almost damaged a motor once doing this. I just put a nut, then the prop and then another nut. Works quite well!

 

[Cyberdactyl]

I just mentioned this to the guy who posted 'My scratch built quadcopter' out in the multirotor article section that is clamping the prop down on the bell.

"The Hextronik DT series is frustrating to some flyers because of the way they mount the props. Many complain the DT750 have crappy bearings, and those replacement bearing are a popular item at HK.

You have the props clamped between the bell and the nut. That puts a tremendous shear on the inset grub screw holding the bell to the shaft. When and if the shaft slips upwards on the bell, even a few hundreds of an inch, it transfers that shear to the bearings, greatly shortening their life."

And don't worry about the 3/16" or so of unsupported shaft, that's really not that detrimental IF you cut off the excess shaft above the top nut.