I'm going to risk disagreeing with a "pro" on this one--but only somewhat. IF the model is a very lightweight stick-and-tissue type thing, you could weaken the structure of small pieces by sticking the pin through the parts. In this case, simply crisscross two pins over the top of the part to hold it down. Tape, weights, and lightweight clamps (or clothespins) will also come in handy for holding things that need to be held together or down to the building board. Having said this, I have been sticking pins through larger pieces for 50 years, too. You can get different grades of pins in the fabrics section of Wallyworld. While you are there, check out the cutting surfaces and some of the nifty tools you may be able to use in your shop. Good luck, Dzl