So yesterday I cut purpleheart with Pegas Modified Geometry #5 reverse tooth blade and my cuts were burning terribly. Then I remembered that I had bought theLP-Lube Stick at Lesley's Patterns. And let me tell you, after putting that on the blade, it cut through the purple heart almost like it was butter. No more burn, no more effort. http://www.scrollsawbladespatterns.com/scrollsaw_accessories.htm I repeated the process several times and the blades lasted a lot longer too!