If you don't mind spending a few dollars, go to the quilting section of your nearest fabric/crafts store and buy one of the mats designed for use with rotary cutters. Olfa is one brand, but there are a couple of cheaper brands floating around. These are maked with a 1" grid(there is a metric version available also), and several common angles. 30, 45, 60 and 90 degrees on the one I have.

I have the Olfa RM-SG which measures 24" x 18". Pair one of these up with a metal yard stick, and a rotary cutter, and you've got a great cutting system.

Some alternatives are the white plastic cutting boards in the housewares section, rubber gasket material, conveyor belt material and a mud flap for a tractor trailor.

A 2' x 4' section of 3/4" particle board can be purchased in most home improvement stores for just a few dollars, and is good surface to cut on due to the lack of grain. Yes, it will get scratched up, but at least your knife won't try to follow the wood grain, and it's large enough that it ought to last for many, many projects. Especially when you realise that you have two sides to work with.

HTH,
Randal

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