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models
in smaller scales
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Author's
oddball, a 1/72 Brewster Buffalo made from the old Revell
kit. Many improvements are included as well as some
genteel weathering.
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Virtually
all of the techniques described in this book are applicable to the
smaller scale of 1:72 (or even 1:100 or 1:144) with some exceptions.
Of necessity, some detail is best omitted in these smaller scales
unless the modeller has the skill of a miniaturist combined with
that of a master watchmaker. Nevertheless it is perfectly possible
to detail the cockpit of a tiny 1:144 scale fighter made from a
kit and it has been done, albeit in simplified form.
The system of
the core and skin method for wing construction is not suitable for
1 :72 scale models except when building large biplanes. The skin
method using 10 thou card results in a trailing edge which is too
thick for the small model and an alternative technique can be employed.
The wing is cut from a sheet of 20 thou (or 40 thou depending on
the model) and shaped in the manner previously described by sanding
with a block. With plastic card this is easy , and the old danger
of the wing splitting as it does with balsa is avoided. The trailing
edge can be brought down to almost a razor thin appearance, the
final finishing being carried out with 'wet and dry' paper liberally
lubricated with soap. To obtain camber, and it should be noted that
camber on a small scale is very licnited, the wing can be bent very
slightly and placed on a former made from spare balsa plank as shown
in the illustration. Strips of balsa are then placed along the leading
and trailing edges and the entire unit plunged into a pan of hot
water (it need not be boiling) for about ten seconds and then withdrawn
and held under a cold tap. The wing will retain the camber when
cold. The former need not be made for one wing only, for it can
be used over and over again. Hardwood is, of course, more durable
than balsa and is more suitable for the permanent rig. After the
camber has been formed the wing ribs can be made from sprue as shown,
the tapes on the under surface being lightly scribed with a razor
blade. The ailerons are cut out last and stuck back in place, after
the necessary rounding off their leading edges. Other surfaces are
made straight from sheet card and the construction is straightforward.
An alternative
technique is to shape the wing as described above, but cover the
top surface with a 5 thou plastic card skin as previously described
for improving kit models. This requires great care when handling
the adhesive but a slightly better appearance of wing ribbing is
the result. Wings with sweep back of course have to have the panels
made separately. Dihedral is achieved by lightly cutting across
the chord and manually forcing the bend. If done gently, and the
initial cut is not too deep, the dihedral will form easily and the
open crack underneath can be filled in the usual way. The wing is
too thin to allow holes for struts, but the location must be made
by scratching some mark which can be seen after painting. The paint
must be removed from this area before the struts are put into place.
Some early 1:72
scale kits still on the market and depicting post-1936 fighters
with retracting undercarriages, had the wheel wells marked on the
under surface of the wings and not actually cut out. Where the wing
comes in two pieces, upper and lower, it is possible to cut out
the wheel well area within the moulded marks by drilling and cutting
before assembly takes place. Where the wing is in one piece, one
way out (though it is 'cheating' to a purist) is to paint the wheel
well area in grey. Though not very desirable this is the only really
practical solution on some tiny 1:144 scale models where there are
no wheel wells and the wing moulding is itself very thin.
Forming
camber on 1:72 scale wing (solid
plastic card construction). Wing is first shaped and sanded and
then put in the rig illustrated. This need be nothing but a 1/4
inch balsa base with two pieces of 1/2 inch square top pieces. A
thin wedge with rounded edges ( avoid corners at all costs) is placed
under the wing about one quarter of the chord width from the leading
edge, and the leading and trailing edges are forced down as shown.
The top pieces are held firmly in place with small 'G' clamps at
least two per side but this number can increase with larger wings.
The entire rig can then be dropped into a pan of hot (not boiling)
water and left there for about ten seconds and then withdrawn and
run under a cold tap. Note that the inside corners of the top pieces
are rounded off. The rig can be made from hard wood and used over
and over again. The wedge should be very fine unless a model of
an early aeroplane, with a considerable camber is being modelled.
Some later biplanes had such a slight camber that it is not necessary
to carry out this procedure at all. An exaggerated camber can look
as bad as a zero one so careful checking of drawings and photographs
should be carried out.
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