How To for making a body side jig for Ian Kirk kits.

This thread is written for the benefit of everyone wanting to build Ian Kirk kits and hopefully covers the "how to" construction of a simple body side jig enabling builders to accurately put together the plastic segments found in a Kirk rolling stock self assembly kit. The jig is a simple flat wooden block with a movable start point and a marked end stop, the jig will allow the builder to make multiples of a carriage body side all to the same dimension thus making the putting together of completed sides to their end bulkheads easier since everything will be the same length. There is nothing more frustrating than discovering one side is 0.5mm longer or shorter than the otherside, this often happens because too much pressure has been applied to the setting solvent which has compressed the plastic sides or, maybe a little too vigorous removal of flashing has resulted in the segments becoming accidentally shortened. Either way this jig will help overcome these issues, view this jig as a measuring tool.

So start off with a flat piece of wood which measures about 20 inches long and 2 1/2 inches tall by about say 8mm thickness, hardboard, ply or MDF is unsuitable because it warps if damp and you cannot trust ply to be a truly flat surface. A piece of engineered wood flooring laminate is ideal. Now you need to create a trough on top of this "plank" running the length of the coach body, this allows for the insertion of a length of Plasticard strip which you will glue the many segments onto, the depth of the trough equals the thickness of the Plasticard strip, in my case I use 1mm thick Plasticard. So you now need to cut some 1mm thick wood veneer into two lengths measuring the full length of your "plank" and 19mm in height and 29mm in height. The 19mm piece goes on first at the bottom of the plank and the 29mm piece is set above at a distance of 15mm apart. Make sure these two pieces are parallel and that a 15mm strip of Plasticard can be lifted out without difficulty of being trapped.

Now you need to add a fixed base point, I used a piece of wood with a planed face edge which measured 14mm x 8mm and glued it on top of the 19mm veneer piece set back from the 15mm trough by exactly 1mm, this makes an allowance for the thickness of the coach floor which will sit inside the bodyshell. The critical edge of this piece is the side which will be in contact with the bottom of the plastic segments, this is also a kind of straight edge and when gluing the segments it is important to take care observing that all segments make flush contact with this bottom line straight edge, or else you will end up with a coach side that resembles a dog's leg.

Don't forget when you glue the side segments together onto the Plasticard reinforcing strip the whole unit when dry must not only be totally flat but also must be parallel , this means the floor piece must fit inside the body without showing an edge and that the both sides when made up must also be of equal length. As a reinforcing strip 15mm is a good size not to be seen and will not impede window and door openings when it come to the glazing process.

So you now have the basic jig table you now need to work back from right to left marking the coach length positions with a scribe and pencil, for example depending on which coach you are making will now depend on where you position a removable end stop. The end stop can merely be a thin piece of flat wood with a straight edge and fixed with drawing pins. This straight edge is the start point for the body side build and makes a 90 degree angle with the bottom line fixed base point mentioned earlier. I varnished my jig just to prevent moisture affecting the wood. This is a reasonably quick and cheap method of making a reliable jig, I have made half a dozen coaches on this jig and all have gone together with ease.

 

There are two big advantages Dundee Paul with using a piece of engineered timber floor laminate, 1) it is totally flat and 2) it has a true face edge and face end, so setting up the parallel jig faces is easy.