Fitting the Sceadu Evo 50 head and main gears to the heli
| Author: | Rob Turnbull |
|---|---|
| Article Date: | 30th April 2007 |
There are two holes in the base of the Sceadu main shaft. If you use the upper hole you will have less overall pitch range available to you. The lower hole, therefore, gives you more pitch availability.
Choice of hole affects overall pitch availability
If you have the driven tail (separate) gears, you can make fitting them easier, by lining up the mounting holes in the gear, and then locking them together with a hex driver (temporarily).
Line up the holes on the driven tail and main gears
Hex driver to keep them lined up
Slide the main gears into the body of the heli and centralise them (looking down at the heli from above the main bearings) ready for the main shaft to be fitted. Visually line up the lower bolt hole in the main shaft (to get the most pitch range) with the bolt hole in the main gears, and then proceed. Slide the main shaft through the top bearing, and push down and through the second bearing, and then into and through the main gears, being careful not to push too far if you want to use the lower bolt hole in the main shaft. Push gently down and watch through the hole in the main gears for the shaft descending and the lower hole appearing (hence why we visually line up the bolt hole first).
The shaft should make it into the lower bearing housing below the main gears. Careful alignment at the start of this step will hopefully have made it easier to locate and line up the bolt hole in the main shaft with the bolt holes in the main gears. Fit the Jesus bolt through the gear and main shaft and tighten the nyloc nut on the other side.
Jesus bolt fitted to the main gears
Loosen the main mast locking collar (already loosely fitted to the main shaft) and slide it down to meet the top bearing. The aim here is to remove any vertical play on the main shaft by locking the mast locking collar as far down the main shaft as it can go, while pulling the main shaft upwards to pull the gears as high as they can go. You may need an extra pair of hands to help with this step.
Hold the heli down and pull the head vertically upwards, and then tighten the mast locking collar as far down the main shaft as possible. The grub screws in the mast locking collar should be thread locked in place. Once completed, check that there is no vertical play at all by (carefully) pulling the head upwards, whilst holding the heli down. You should not feel any vertical movement.
Mast locking collar fitted
Mast locking collar fitted