A little learning goes a long way............
A some of you
might be aware, I have spend a not inconsiderable amount of time preparing drawings for the build of Free Enterprise V. Now, these I have tried to make these drawings as clear and concise as possible and, with the backing of an instruction book and CD of photos, I am hoping that the build would be straight forward.
HOWEVER
Whilst preparing the sheet of parts for the plug, to highlight the openings, I have been in discussions with a very helpful chap who runs a small laser-cutting business. He is not in the model trade, and he has found the idea of working on this kit fascinating.
It was during one of our discussions about what can be achieved, and what he needed from me to make his job easier, that the issue of the width of the laser cuts came up. It appears that the cut in the plastic has a width dependent upon the thickness of the styrene to be cut. This cut line is called the 'kerf' and is tremendously important in the design of the kit for, if it is not allowed for, then all the accuracy that has been drawn goes out the window.
Chris (for that is his name) is currently cutting me some samples on various thicknesses of styrene so that I will know what to allow, however we already know that a kerf in 1mm styrene is 0.8mm wide. Now, that doesnt seem much, but when you take 0.4mm off two sides of a superstructure wall (0.4mm either side of the centreline of the laser beam), and then multiply that by 10 parts that make up the length of superstructure, that is 18 x 0.4 = 7.2mm. In effect, the superstructure would be 7.2mm SHORTER than designed!!!! On any model that is noticeable, let alone one at 1:96.
SO
Now that we know that laser beams cut a width based on the thickness of styrene used, I have to now go back through all my production drawings and increase the size of all the parts by 0.4mm all round. Once the laser has done its job, the final part will end up being exactly the right size and, in theory anyway, all the parts should fit!!!!!
There is a lot more to this kit production business than meets the eye...
All the best
Carl