A couple of yrs ago I bought the cutting table and the large matt from JoAnns. Then a month later bought a brand new rotary cutter from the quilt show, this thing cut fantastic. I took it home and only after a few cuts it seemed like it was dull, so I was upset because I thought I'd been dupped at the show. I pulled out one of my other cutters that I knew worked great, same result. It took me a little time to figure out that it wasn't the blade it was the matt. It wasn't self healing so once it had been cut on a few times that area would only cut the fabric hit and miss. I used a different section of the matt and all was fine. Now I just put on my self healing matt and only use the table top sized matt to protect the cutting table. Try your blades with either a different matt or on the reverse side to see if its the blade or the matt that is the real problem. I've saved many of blades since using this practice.