The head works fine the first time, but after that it needs to be sharpened with a diamond stone. Making small cuts of no more than 1/32" to line up a 3" wide x 14" long spruce board worked well. I expected the edge to last a few times on the cutter before needing to be sharpened .The seal on the plastic box that the cutter came in was broken.High cost to replace the bit after such little use.Poor quality product.I would not recommend or buy this item again.This is the quality I expect from in Chinese made products.