Skyranger Nynja, Build Manual

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Nynja Build Manual 1.4d
e) Bleed the brake system until the brakes become effective at preventing the
plane being pushed. The lever does not have to be very hard to achieve this.
Ensure that no brake fluid is spilt on anything. If any is spilt, wash
off with copious amounts of water. Use containers / oven trays etc. to
catch any fluid dripping off the reservoir or running down the stick.
Beware of spurts of fluid out of the reservoir filler or the bleed nipples.
Fill the system from the bottom up through the calliper bleed nipples,
using the syringe supplied or a pressurised bottle available from
Halfords or similar. This seems the most reliable method and should be
used. To get firm brakes it will be necessary to push enough fluid
upwards in one go to fill the calliper and the brake lines and flood fluid
out of the master cylinder (use plenty of rags and a catch tray to
p
revent fluid spilling on the airframe). A ‘stop start’ approach will result
in bubbles of air being trapped.
Figure 90 brake bleeding
f) If the brakes leak fluid they will require more sealant tape on the threads.
It may appear that the brake callipers are leaking from the seal between
the two halves. This is unlikely to be the case: typically some fluid from
a leak on the bleed nipple gets between the calliper halves, and can
then be seen as a line when the brakes are squeezed and the callipers
flex slightly.
The hydraulic fittings on the brake callipers may need to be tightened
up quite a lot to prevent weeping of fluid.
Run-in the brakes on the ground before flight testing commences.