There's no law about what goes into which magazine, but MEW is tools and TECHNIQUES.
For example, we could cover the techniques used in making an injector (e.g. making and using small taper reamers and concentric opposed bores) though we wouldn't publish an injector design, because the techniques have wider applications and interest.
Also, this chap is fabricating replacement/new parts for his machines and wants them to fit in. In my own small way i have fabricated the base for a dividing head from two parts screwed together with a fillet of epoxy for aesthetic reasons.
Ah! I see Jason has made the point nicely already.
Neil