Springs
Hi, all,
As there evidently will be more builders/owners fitting the stainless steel nose
gear springs developed in Holland, here is the method I used to install mine:
1. Keep the safety wire as per Europa's Builder Manual
2. Measure the length that the springs must be extended to in order to enter
over
the upper and the lower tubes. Do this with the stopper against the upper
tube, which requires that the nose wheel is free off the ground.
3. Extend the springs to a little over this minimum length.
I did this with a hydraulic 2 ton car jack. I placed one crowbar under it
and one on top (crowbars can withstand a lot of bending moment) and hooked the
springs over them - one on each side of the jack.
4. Insert suitable bits of steel between each coil, all the way from top to
bottom,
one on each side of the spring (i.e. 180 degrees separation), to keep the
spring extended when removed from the jack.
I used plain nuts ( 5.3 millimeter thick, but the required thickness may
vary
some), held in place by one strip of tacky tape on the outside of the spring
until I depressurized the car jack.
5. Depressurize the jack, and verify the correct length of the two springs.
5. Place the springs over the upper and lower tubes. You need to wriggle them a
little to get the last one in place, which you probably will find has to be
placed
"turned around" compared to the first one (you will understand this when
you get there).
6. The attack point of the springs on the lower tubes must be as close to the
center
as possible, to reduce the bending moment since the outer ends of the tube
are not supported (recommendation by EMIL).
I used hose clamps around the lower tube, on the outside of the spring
hooks,
to prevent the hooks from sliding outwards over time.
7. By introducing pressure on the nose wheel, sufficient to open up the
springs,
all the small steel pieces (the nuts) will fall out, and the job is done.
I did this the following way, whereby one does not need to excert any
pressure
at all on the gearboxl:
- Rotate the nose wheel as for pushing the airplane backwards (this
increases
the moment arm of the nose wheel).
- Lift the fuselage at the tail. I used a strong point in the ceiling of
my work shop, and a baggage strap with ratchet looped under the fuselage just
forward of the fin.
- When one of the main wheels has been lifted a little off the ground
(meaning
that sufficient weight has been shifted to the nose wheel to stretch the
spring), you will hear the steel pieces (nuts) falling out. Before lowering the
tail back down, check that all the steel pieces (nuts) have actually fallen
out.
The entire operation took maybe 30 minues, and now I will have no more worries
about slack bungees. - Thank you, Tim!
Regards,
Svein
A-225 - now in Norway
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