Great Central Models Robinson GCR Class 8B Atlantic LNER C4, Инструкция по сборке

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Page 18 GCR Class 8B
Page 18 GCR Class 8B
File down the top and bottom carefully so that they do not hit
the Slide Bar Supports (22,23) and can move freely along the
length of the slide bars.
Coupling Rods
Note
The coupling rods are a mirror pair - so take care that all the oil
boxes end up at the top!
A range of extra parts are provided either full depth or half
etched to be attached to the bosses on the coupling rods either to
the front or the rear. These will allow you to choose how far to
off-set the wheels from the coupling rods. The boss at the rear of
the coupling rods is optional.
There is very little space behind the connecting rod in P4 so if
using the Alan Gibson crank pins and locknuts then the leading
hole in the Coupling Rods Left and Right Front (105,111) should
be opened up to 1.8 mm so that the locknut can fit into into it in
reverse. In Extremis is it just possible to open out the hole in
either top boss or the overlay to 2.5 mm so that the whole nut is
countersunk.
A better solution may be to use the crank pins designed by Tim
Venton (see Scalefour Society Forum). These are threaded and
the front one is countersunk into the coupling rods hole.
Drill 1.5 mm to 1.6 mm through all the other crank pin holes to
suit your crank pin bearings. The front crank pin is rather shorter
than on the other axles if the crank pin nut is reversed.
Drill out the coupling rods to suit your choice of crank pins.
Remove
Coupling Rod Left (105) , Coupling Rod Left Overlay
(106) from the fret.
Remove Coupling Rod Bosses (107-110) from the fret, select and
solder in place to inside and/or outside of main coupling rods.
Repeat for the right side coupling rods using parts (111-116).
Connecting Rods
Note
The Connecting Rods are a mirror pair.
Remove parts Connecting Rod Left (117) , Connecting Rod Left
Overlay (118) , Connecting Rod End Overlay (121) (square),
Connecting Rod End Overlay (122) (round) from the fret and
solder together.
The hole which fits over the centre axle crank pin should be
opened out to (1.5 mm to 1.6 mm) to suit your crank pin bearing.
The small end of the Connecting Rod should fit inside the
Crosshead Assembly and is secured with a 0.5 mm rivet (lightly
hammer in place or soldered on the rear according to
preference). A short piece of 0.45 mm brass wire will suit as well.
Leave the front slightly proud to represent the fixing bolt.
Repeat for the other connecting rod.
Buffers Beams - rear
Note
9. Connecting Rods
Connecting Rod Left Overlay (118)
Connecting Rod Left (117
Connecting Rod End Overlay (121)
Connecting Rod End
Overlay (122)
8. Coupling Rods
Coupling Rod Left Overlay (106)
Coupling Rod Bosses
Coupling Rod Left (105)