Today I had quite a tussle ripping oak. A little over 1.5 inch thick two foot board literally stopped my TS55. Acted like it was binding, even ended up with burn marks on the oak!! Never had a blade sharpened but I don't use it that often so was a little surprised. Evidently this was one tough board as it literally snapped my counter sink bit even after I "pre-drilled" the hole. I've never worked with oak that thick so I'm wondering if this is normal or maybe time for a new blade?