>>By the way, about this sternpost?<<
Yes, I've sold a few including one to Tony K . L70 + postage. It's quite long,
obviously, in fact outside limits for UK post but they don't seem to mind. I've
only used it twice, took me a day to finish Charlie Laverty's fin.
If Europa go to a castoring tailwheel it will help a lot.
I have one electric horizon and inverter. It's a Sperry HL 9 E. Heavy (about 4
lbs) and it has the old black face, but it works. Looks clean.
I've forgotten where you live. I have relatives in Perth and Melbourn whom Joan
and I hope to visit soon. We also want to see NZ.
I'd certainly buy a few scissors. One never seems to be able to find them when
one needs them. I would be most grateful for a pair.
Sternpost instrcutions follow:
Croft Cottage, Longway Bank, Whatstandwell,Derbys.DE4 5HU
Tel.01629 822 725 E'Mail : 100421.2123@compuserve.com
Sternpost
The part consists of two plies of BID reinforced on the flanges with the two UNI
layups specified in the plans. The flanges are peel plied on both sides. Remove
all peel ply just before bonding the part in place, not forgetting the peel ply
applied to the fin, your first layup. Delaying removal helps to prevent
contamination and ensure a good bond. It is still advisable to scuff sand
lightly, because of the slight risk that the peel ply itself could leave some
contamination on the surface. This advice is based on research done by John
Tempest at Cranfield University.
Fitting of the fin, fin spar,( or sternpost ) is quite an involved process,
requiring location of several loosely defined points and lines in space. The
rudder needs to be trial fitted before making the lay-ups which form the
sternpost; this entails Clecoing the rudder hinge to a thin, floppy two ply UNI
flange. This premoulded sternpost will greatly aid the process by allowing the
fin and rudder to be accurately set in place, adjusted and even connected up to
its push rod before finally completing all the lay-ups.
Start by reading the Europa manual so that you are completely familiar with the
whole procedure. Do not trim anything off the trailing edge of the fuselage.
There is no spare material on the right hand side.
After removing the surplus blue foam from the fin trailing edge close out (leave
the peel ply on until the spar is floxed in) carefully relieve the foam as
necessary to allow the sternpost to sit snugly in place. This is to allow space
for the leading edge of the rudder at full left deflection. The top end of the
sternpost should be trimmed to match the profile of your fin, which will be
slightly different to everyone elses. Take off only enough to allow the tapered
sternpost to move upwards until it just fills the space without spreading the
trailing edge of the fin. Drill for four 3/32" Clecos (or better, Skin Pins) and
assemble.
The lower part of the spar replaces the original piece of plywood and strictly
speaking since it is a shear web should be flat. Carve a piece of scrap blue
foam to fit the forward face of the spar, from the bottom of the fin to the
lower end then micro it in place. Level it off so that it becomes a wedge and
cover with two plies of BID, overlapping 15mm onto the face of the spar and just
covering the foam where it will lay against the side of the fuselage moulding.
Peel ply this part of the lay up and allow to cure.
This assembly can now be offered up to the fuselage, trimming the bottom of the
sternpost as required. It would be wise to start with a 1/4" packing under the
fin until sure that this can be dispensed with. The aim is to achieve a smooth
line on the leading edge (and to match up the rudder to the fin/fuselage
combination.) It may be noticed that some extra filling will be needed on the
sides of the leading edge just below the joint with the fin. This arises because
the original fin had less sweep back than the present rather racy looking
device. At this stage the rudder needs to be offered up to make sure it will
enter the trailing edge. It will almost certainly be necessary to sand off part
of the top at the leading edge, and probable some at the bottom. The rudder
should line up with the top of the fin and just fit into the fuselage at the
bottom.
Select two good straight pieces of aluminium extrusion, 1 by 2" angle would be
ideal, or channel section. Wood strip might do but isn't always stiff enough.
Then, clipping these to the trailing edge get everything adjusted and when
satisfied Cleco the fin to the fuselage.
The rudder can now be fitted, as described in the Europa manual, trimming back
the RH flange of the sternpost to allow the hinge to fit snugly. This is the
time to see if anything needs to be trimmed off the RH fuselage flange. Bond the
two straight edges to the trailing edge flange with Bondo using sufficient
spring clips to pull any distortion out of the flanges and allowing enough space
aft of the straight edge to fix the rudder in place with a Cleco in each hinge
and two in the bottom one. Now make sure there is enough clearance to allow at
least 32 deg deflection to the left before the rudder leading edge touches the
sternpost. The LH flange will need to be trimmed off to allow this. Don't take
off too much or there will be a gap when the rudder is in line.
Bond the fin to the fuselage as described in the Europa manual. The inside
surface of the fuselage will need to be smoothed where the sternpost is going.
Grind off any lumps, but NOT the thick areas of the fuselage joint overlap, some
foam may need to be removed. Then replace any of the inner skin that has been
removed with one ply of BID, overlapping 30mm forward of the corner of the
sternpost. Peel ply and let cure.
The sternpost can now be bonded in. Mix up Redux with just enough flox to
prevent sagging under its own weight, spread the Redux over the bond area,
thick in the centre of the flange, thinner towards the edges. Remove the peel
ply from the spar and lightly scuff sand the surface.b Finally bond in the spar,
using spring clips every few inches as necessary to achieve a thin bond line.
Check before cure that all air has been pushed out of the joint line, bubbles
will show up against the dark blue green Redux. After cure complete the
sternpost by removing the rest of the peel ply, scuffing the inside surface and
adding the hinge reinforcement lay-ups. Let cure, preferably leaving the two
straight edges in place for at least a couple of days.
regards
Graham
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