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Modelling TechniquesSee Also: Why use glue to make a cart or waggon frame? There is a quick retort, why not? If it looks right, does it matter? No, the point being made concerns the achievements and frustrations of the wheelwright, when glue for him, was not available. If you wish to follow in his footsteps, then you must emulate his ways to find out how it was done. Here, we are restricting ourselves to his mortise and tenon joints which are superior to gluing two pieces of wood at right-angles to each other, and are so easy to cut at 1: 16 scale, and even easier at 1:12 and 1:8 if those are the scales that you prefer. The secret, if there is one, is not to pre-drill the mortises, which makes it difficult to stop the chisel from slipping into the hole. Although the width of the mortise is traditionally just over 1/3rd of the width of the timber, the final width is governed, not by measurements, but by the width of the chisel, mortise gauges are set to the chisel, though they are unnecessary at model scales. Using 1/16 and 3/32 inch flat swan-necked gouges or a 1/8 inch bevel-edge chisel for 1:16 scale, will cut equivalent 1 inch, 1½ inch and 2 inch mortises. The last chisel gives the game away; the back, as in all mortise chisels, is ground off so that it is not as wide as the face, in order to clear the hole and prevent it from sticking. Tiny flat gouges can be ground off in the same way. The sharpened angle does not need to be blunt like that of a mortise chisel, as long as you realise that it will not be as robust and you must be careful not to snap it. At this scale, no mallet is needed, for the chisel can be pushed into hardwood. Neither is it necessary to mark out the joint conventionally, just mark a centre line the length of the hole, and straddle it with the chisel. The grain of the wood keeps the hole straight. Wood with a straight grain helps. At 1: 8 scale, oak can be used for framing just as the wheelwright did, but at 1:16 scale the finer grain of Ash gives much better results. Hold the wood in a vice. Begin by making a cut at each end, with the face of the chisel facing outwards; then in order not to crush the ends of the hole, do not touch these cuts until the very end. If you push little cuts with the chisel all the way down the line at 1:16 inch intervals, the grain collapses, and the little pieces can be levered out from time to time. Do not force, and break the chisel. When the depth is approximately halfway through, turn the wood over, and work from the other side after ensuring that both holes will coincide. Soon you will go right through, and the pieces will fall out. Finally clean up the ends where you made the first two cuts. It is simple! Stopped mortises are not more difficult, but require a little more patience The tenon is cut to fit the hole. The end of the wood is held up against the mortise, and marked from it using a sharp pencil and your fingers to form a thickness gauge, ready for sawing outside the line. With a square, mark off the haunch end in the usual manner. A method developed in the Northumberland shipyards for sawing tenons has stood the test of time. Hold the wood vertically in the vice with the cutting lines at right angles to the length of the bench. Start the saw-cut on the back edge of one of the lines, and work towards you, and down, so that you can see what you are doing. Leave the far edge uncut to hold the saw in place Do the other line, turn the wood round and make two more cuts in the same manner; then saw down horizontally, using the previous cuts as a guide. This method reduces all errors. Then turn the wood horizontal and cut the shoulders so that the waste falls away. On a good day simply hammer in the tenon, but on an irritating one; ease it in with a file. Always make a through tenon a fraction too long, to clean off flush, or to leave protruding as they usually are on a vehicle. If you have your own method, that's fine. The model will be much stronger, and look more realistic for your efforts, and you will have the satisfaction of working as a true wheelwright or joiner. An exception is preferable when mortising naves. Here the hole must be in exactly the right position and must run in accurately to the centre, so a dividing head is advisable. Start with a ring of vertically drilled holes at the back ends of each mortise. Then set in the angle of dish on the front ring of holes. Note that the back ring is always drilled at right angles to the axis of the nave and the tenon tapers. A mortise and tenon is a sophisticated joint that has stood the test of time for builders, carpenters, wheelwrights and shipwrights. It gives great satisfaction both to the maker and user. Once you have tried it you won’t want to glue the pieces together again.
SUGGESTED TOOLS FOR MODEL HORSE DRAWN VEHICLE CONSTRUCTION. BASIC TOOLS CUTTING TOOLS Shears and tin-snips (Universal, tinman and Jewellers) Cutters for soft and meduim metal) Scissors Cutting mat *Miniature tube cutter DRAFTING AND MARKING
MATERIALS Centre punch (1/16") Adjustable bevel, protractor and mitre gauge DRILLS Assorted drills (Imperial,
metric and Microdrills) EDGE TOOLS 1/4", 3/8", 1/2", 3/4") Medium grit stone Diamond FILES Warding files FINISHING TOOLS
& MATERIALS Reamers and broaches HAMMERS Medium Ball pane Pin hammer (4 oz etc) HOLDING TOOLS Pin vices MISCELLANEOUS Screwdivers (normal and precision) Tweezers DIY jigs to suit the job you are doing made from the available tools and scrap materials PAINTING (see also Finishing Tools & Materials) Good quailty paints (Humbrol Phoenix etc) (acrylic, matt, gloss etc) Good quality artists paint brushes (Preferable sable) *Airbrush (Badger, Draper, Humbrol, Vivolor similar make) PLIERS
SAWS X-acto razor saw (for very fine work) Record mini-saw Gents saw Coping saw Fretsaw and blades (assorted grades for thickness of work in wood and metal Piercing saw *Band saw *Jig Saw Mitre boxes SCREWCUTTING BA taps & dies (2 – 12BA) Circular die holder (for above) Tap wrench (for above) SOLDERING TOOLS
& MATERIALS Third hand *Charcoal block TURNING TOOLS top |