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1/48 Douglas
DB-7 Boston |
The kit is very
similar to AMTs earlier releases of the G and J model A20’s.
Fuselage, nose section and carburettor intake housing sprues
being the noticeable, and required changes. Similar standards
are maintained, finely engraved surface detail, basic internal
fittings and good clear parts. It is of note though that
problems in the earlier kits of difficult nose section
and tail surface joins remain, along with the very weird
main wheel tread pattern. Methods of remedying these problems
will be discussed later in the article.
Primary areas of
attention for the conversion revolve around the engine
cowling and exhaust and the nose section. RAAF DB-7’s were delivered with clear glazed
nose sections for the Navigator/Bomb aimer’s station,
and the standard four gun (30 Cal) armament. Like many USAF
aircraft these were converted in the field to eight gun noses
and the third crewmember was removed. Additionally the DB-7B’s
cowlings were fitted with fixed vents following the lower
centre line and a single exhaust port on each nacelles
outboard side. The remainder of the conversion is simply
based around enhancing or correcting the kits detail.
Internally the most effort was expended
in enhancing the kit detail. In the cockpit enhancement
was provided by the addition of seatbelts made using masking
tape and finished with some PE buckles. Wiring was added
to the sidewalls and floor and the small panels mounting
fire extinguisher controls to the lower instrument panel.
A small hand held extinguisher was scratch built and added
behind the pilots seat. As I wanted to display the canopy
open enhancement of the life raft bay was required. Sidewalls
were drilled and fashioned from sheet styrene. The inside
of the hatch was enhanced by drilling out the weight saving
holes, adding a sun screen made out of fine wire and tin
foil, and scratch building some internal details and latches.
The bay was finished with the addition of a scratch built
life raft, in hindsight the available resin accessory would
have looked better. The mid-upper crew position required
a little more effort.
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Internal ribbing was scratch built
along with racks for ammunition boxes. Visible cabling
was added, as was controls for the opening of lower hatches.
Seatbelts for the crew station similar to the cockpit were
added and the barrels for the twin 30 Cal guns were replaced
with hypodermic tubing. Careful washing and dry brushing
completed the respective cockpits.
Fuselage
and nose section
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The fuselage was
joined without incident once some small guides were made
for the bomb bay doors. At this point I added the horizontal
tail surfaces, vertical surfaces would follow later. The
hole at the rear of the fuselage was covered with styrene
and the clear tail light cover added. These were then sanded
and polished to an acceptable finish. Work now commenced
on the nose section.
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In this area lots
of dry fitting saved my bacon. It was found that the two
piece lower nose was smaller than the fuselage width, but
the glazed section was the right size. My solution was
to add a 2.5 mm spacer between the lower sections and join
these to the clear before fitting to the fuselage. No filler
was required between nose and fuselage but some sanding
of the clear parts was required. This sanding removed some
of the raised detail on the clear parts, and as a result
I removed it all. The conversion to an 8-gun nose replaced
plexiglass panels with aluminium ones so preservation of
a clear surface was not required. The raised detail previously
removed was replaced with very fine masking tape and sealed
with a clear varnish. Four holes were drilled into the
forward flat surface of the section and all 8 MG barrels
were replicated with hypodermic tubing. Work now commenced
upon the wings and tail.
To make the vertical tail
surface accurate a little effort is required. Firstly the
two kit rudder mounts were hollowed out with a scribe. Two
small triangular pieces of styrene were then added to replicate
the flat rudder mounts. A scratch built two piece housing
for the rudder trim mechanism was then added to the lower
right side of the fin. The assembly was then placed on the
kit and substantial filing was completed to gain an acceptable
join.
The wings were joined in
the standard manner before fitting. In order to get the right
dihedral the kit comes with a form of main spar, but a couple
of mm needs to be shaved off the bottom at the ends in order
to get the correct effect. This also helps in reducing the
amount of filler and sanding required for the wing to fuselage
joint.
The kit engine nacelles
require fair amount of work to firstly improve the accuracy
and secondly, be converted to DB-7B standard. Work commenced
on the inboard side oil cooler intakes. The kit provides
intakes and vents that open directly into the undercarriage
bay. Using sheets of styrene cut and bent to shape along
with some stretched sprue the required vertically divided
intake was created. A similar method was used to represent
the exit vent. After significant dry fitting the outboard
side was cut and a mount for the single exhaust was built.
Care should be taken here that the mount does not protrude
into the undercarriage bay so much that it interferes with
the upper legs. The two halves of the nacelle were then joined.
There is a lot of scope here for further detailing as the
internal bay is very sparse.
However from experience
with the G model any scratch built detail will not be easily
seen, accordingly I added no further detailing. The nacelles
were then joined to the wings, some small spacers in the
locating recess helped to achieve a join that did not require
filler. Both nacelles were placed over the already inserted
upper undercarriage mounts, less the leg.
The kit undercarriage though
basic is reasonably accurate in all areas except for its
placement. The locating holes given mean that the legs are
placed much to far to the rear. I alleviated this problem
by creating new ones 4mm forward. This was not quite enough
and if I were to build another, a 6 mm move would be used.
The kit engines are quite
basic, but have scope for improvement. The only improvements
I made was to add ignition leads. This was done by painstakingly
drilling mounting holes for all leads and then threading
monofilament through. Small clips to hold the leads together
were made from styrene before careful painting, washing and
drybrushing was completed to produce an acceptable finish.
The fixed vents were produced
by marking the holes out with pencil, before drilling and
squaring off with a fine hobby blade. The inside of the cowl
was then thinned down with a motor tool. I had some designs
to replace the scribed cowl flaps with some scratch built
ones but baulked at the effort required to scratch build
the visible detail at the rear of the engines. Accordingly
the flaps remained in the closed position.
Finally the single exhaust
was fashioned from brass tubing, with the opening suitably
thinned to scale.
The remainder of the kit
was built as per usual with the addition of replacing the
nose gear doors with ones that were of scale thickness and
opening the boarding ladder hatch. A scratch built ladder
was also added in its deployed position. The kit wheels were
used albite with the weird fish scale tread removed, these
remained attached without glue so true details resin ones
can be added in the future. HF antennae and fixed forward
sight were made from monofilament.
22 Sqn Boston’s were
finished in the standard RAF Dark Green Dark Earth and sky
type S finish. This was replicated with Humbrol, Modelmaster
and Aeromaster enamel paints. The kit was given a coat of
Future before decaling and weathering. Decals are from the
Aussie decal range. The aircraft depicted is DB-7B/Boston
III A28-9 DU-K as it was seen in early 1943.
Weathering was achieved
with drybrushing modelmaster aluminium buffing metalliser
and washes of dark green, black, grey and raw umber. Finally
a flat coat from the Floquil railway colours range was used.
References:
Wilson, S. 1992, Boston
, Mitchell and Liberator in Australian Service, Aerospace
publications Pty Ltd, Weston Creek ACT
Flightpath Magazine
Vol 10 No 1. pp. 66-75 article on the RAAF Museums Boston
III restoration.
Images and text © Jeremy
King
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