You can use taps designed for cutting these threads in wood or a special cutter can be used which does a better job but you need a lathe with threading capabilities. This is a small, usually carbide, cutter that you mount into a router or toolpost grinder mounted on your tool post. You set the desired thread count on your lathe and then feed the cutter into the hole you bored for the threads. This makes much cleaner threads than a tap. These cutters can usually be bought for 100 - 150.00. Taps, of coarse, are much cheaper.