I use the Airfield Models magnet system as well, building on top of a piece of 16ga. steel plate. Yes it can be pricey getting all the necessary parts, but the advantages make it worthwhile. Well.. not so pricey if building 40-60 size birds, but a bit more if working on 1/3rd scale and up. Sooo much easier to use than pins. Example, if need to make an adjustment to a framed piece, its very nice to be able to lift the piece off the table, make the tweak and set it right back into the 'magnet frame' that surrounds it.