Turnigy SK3548-900 shaft removal

This motor comes with a bell mounting prop adaptor, which is the recommended way to mount on the front of the firewall. In addition, once this is done there is a collet to be mounted onto the shaft behind the c-clip to give additional security against the shaft pulling out, since all the thrust of the prop will be trying to pull the bell and shaft out of the bearings and off the motor - and the only thing holding around 2 kilo of thrust is that tiny little c-clip on one end and the grub screw locking the bell onto the shaft the other end.

As per this pic from bungymania.com




Edited by SeaComms - 20/Oct/2009 at 5:30pm

Here you go:

http://www.bungymania.com/imageshome/includes3/motorperf1.php?id=73

Yes - and well caught before any problems occurred.  You have to remember that although these a pretty good motors for the price and I have heaps of them and always sing their praises, they are made to a price and unfortunately quality control is not always what we would expect from a motor costing 5 times the price (to be expected..).

Ok so to the point...  Yes, the c-clip should be sitting in the groove, and in this particular installation configuration I always use the collar as well (and no, have never seen any instructions, just trial and error...)  Mine have only one washer under the clip, I would guess two is too many for the positioning of the shaft. If the clip is not in the groove there is nothing to stop the shaft pulling out in your rear mounted application!

I do like these motors, but I also always go over them before first use to make sure of any discrepancies like this.  Also be very careful of the screws that hold the cross mount to the motor - they are usually too long and when tightened will normally touch the motor coils and with some vibration will cut into the insulation and burn out the wiring.  I screw a 3mm nut onto them, lock the nut in the vice and file about 2mm off the end of the screw. That way it ends up flush with the inside surface of the motor. I also use ome blue locktite on them as once the motor is mounted to the plane you cant get to them to check if they are still tight!  The blue locktite though leaves the screws readily removeable should you need to take the mount off at any stage.

Hope some of that helps, Dave.

LOL - good idea Rick.  Personally I havent smoked one myself (yet..), as I always seemed to end up underpropping rather than overpropping, but I picked up a wattsup meter and found it a godsend for checking out this stuff.

Before the wattsup, i was making use of the bungymania website and others reports on the motors in the eshop to get a good starting idea of what to fit it with and what to expect.

I currently use a APC 11X8.5E prop to fly my Great Planes Combat Corsair, weight approx. 3lbs.  I used a 12X6E APC Style prop from HK on my Hanger9 T34 Mentor weight 4-5lbs when I had it.  Couldn't put a larger diameter due to ground clearance.