SHAND MASON FIRE ENGINE IN 1:6 SCALE

Part 3 by GUENTER KALLIES

The swiveling frame, or fore carriage (photo below) comprises two side members (112), which are connected by two cross members (114). The side members can be made from any material although drawn steel or brass profiles are less suitable because they are difficult to bend. Strips sawn out from sheet metal and carefully annealed can be bent in the desired form around a piece of round steel in the vice. Then the final contour is finished with a file.

Clamping the  side members together will create the final shape plus matching drilling positions. The cross members (114) have short plugs at the ends and these can easily be produced by clamping in a four-jaw chuck in the lathe and turning down. It is important that the length of the middle portions are the same. The plugs are riveted in the side members (112). The front beam (113) is fastened to the heads of the side members using countersunk screws, the eyebolts and hooks are located in this crossbeam to attach the harness.



The turntable (117) is made from 3 mm sheet metal. The corner points are drilled and sawed out with a small bow saw or coping saw. Better still would be a scroll saw. A brass socket riveted to the turntable provides the rotation point for the turntable which is fastened to the frame with eight countersunk screws. When drilling these screw holes the frame must be squared precisely, because later correction is not possible. The fittings (110) or (115) for the leaf spring connection are sawed out and riveted onto the frame. The outside edges of these fittings should be chamfered or rounded as shown in the drawing.


The shaft shoe (116) located under the front crossbeam is made from two parts. The U-shaped portion with 12 mm width inside and the upper portion bolted to the crossbeam. Both elements are bent from 1.5 mm thick and 6 mm wide brass strips and brazed together in line with silver solder.


The other fittings on the front beam are also made from brass.

The eyebolt (119)  can be turned, e.g, with a form tool, or with great care by hand using a graver and finishing with a file and emery on the lathe. If you are not familiar with such operations please grind a form tool to turn the ball end. Finally, machine the side faces and cross drill.

Hook (118)

A piece of 6 x 12mm flat steel or brass is the ideal material. First turn down the threaded plug. To do this the material must be clamped in the 4-jaw chuck running about 3mm out of centre. Next the head portion should be machined to the thickness of 2.5 or 1.6 millimetres. After cross drilling, the final contour can be worked with a set of needle files. Lastly, all edges should be rounded smoothly.


Note: not every manufacturing step will be explained in these articles or every individual part mentioned. Components that are very simple, e.g. the slope irons (120) or (121), do not require any explanation. However, such parts used

used in pairs should be clamped together for shaping and drilling to ensure equal distance of the holes.

Bunker (122) This is fastened to the bogie in-between the front wheels. Make this box from 0.7mm brass sheet metal by cutting and bending according to the drawing. Bending can be done over a wooden form block using a mallet or soft-faced hammer. The form block corners should have smooth radii on all edges to avoid the metal cracking.

It is important that the metal is well annealed prior to bending, so that the spring back effect is limited. After bending the box, the corner profiles (124 and (125) are riveted in place.

With the assembly of the front vertical corner profiles (125) a sufficient slit for the sliding plate has to be left. The sliding plate (123) is cut out of 1.6mm brass sheet and should be in place when the corner profiles (125) are drilled and riveted. For the ‘hand hole’ in the sliding plate two 6mm holes should be drilled and the material in-between worked out with a small file to an elongated hole. The bunker is fastened to the side members of the front bogie using four M3 screws.



Brake parts

The brake system works on the rear wheels only. The shaft brackets (126) are made from brass and fastened from below to the girders of the chassis using two M2.5 screws each. The crank arm (128) is produced from 6mm dia. round steel. First the 5mm plug is turned down, then the lever can be bent and filed to shape in the vice. If steel was selected to make this component, hot bending is recommended. A cross-drilled pivot is riveted to the lower end of the torque arm (127). Make sure that these pivots are only loose riveted and that they can slightly rotate.

The keep plate (129) is easily produced and no instruction is needed. The brake shoe is made of two parts: the shoe (130) made from brass and the brake pad (131) of Tufnol, fibre or hardwood. Both parts are held together with two small M2 countersunk screws. On the left side of the vehicle a footstep (132), (133) is attached to the brake shoe in place of the plain keep plate. The footstep assembly consists of the shank (132) and the step plate (133). The chequered plate can easily be produced on the centre lathe or in the milling machine using a 60deg. 'D-Bit or fly cutter. Line by line can be cut to the distance of approximately 1mm, first at 45deg. and afterwards at 135 degrees.

The eyebolt (134) for the shaft bracket (126) is made from two individual parts brazed together. The 3mm dia. hole should be drilled after brazing.


The brake levers (135) are sawn from a piece of 2.5mm steel sheet metal and may be held in the 4-jaw chuck for turning down and threading the spigoted ends. The handles (136) are turned from a piece of round brass or stainless steel and tapped in the centre for screwing to the levers.



Both brackets (137) can be produced in one operation. Make the profile from a brass bar, including drilling, and separate it afterwards into two pieces of the required length. The common axis of both brake levers is more complex. Two rotary parts (138), (139) fitted together, form the complete axle. This allows separate operation of the left-hand or right-hand brake lever. The tension rod (140) and the fork head (141) and the bolt (142) make the linkage between the brake lever and the rear brake gear assembly. The components are so simple

that detailed description is not needed. All dimensions necessary to make them are given in the drawing. The fork head (141), which is made from 6 x 6 square brass stock, requires some explanation. First it is turned down to Ø 5 and threaded. Next step is to cut the part to length, cross drill and slit. Finally it can be trimmed to the final round shape.


The last component of this assembly will be the rack frame including the lamp bearer. Three separate and individual parts are needed, the rack (143), the lamp bracket (144) and the lever guard (145). The rack is made from a 10 x 5 mm piece of brass. The ratchet teeth can be cut in the lathe with a fly-cutter or a profile cutter to give 60°(photo below).

The lever guard is made by turning and threading a piece of 3mm brass rod, then bending it to right angle. The lamp bracket is made from a piece of 3mm brass sheet metal, held in the four-jaw chuck to turn it down and screw to form the stud. Finally cut and fill to shape. The vertical part of this piece is tapered at the top end, to serve as a lamp bracket.

The bolts and nuts necessary must be selected during the assembly. Generally hexagonal head bolts are to be used. The positions of the individual components is given in the assembly drawing for drilling.


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