Up until this past month, we nearly ALWAYS used down cut bits as we are always trying to limit the amount of tearout we get on our veneer plywood. I can safely say that 9/10 times we DO NOT use up cut buts because of the ragged top edge it produces. However, we are now starting to use compression bits and our assembly guys are loving them and we are resurfacing our spoil boards much less frequently. I think we just recently cut 25+ sheets of MDF and the spoil board looked like there was more missing than remaining and we were getting great cuts on both the top and bottom edges.
To answer your question about how much concern is there when using an up cut bit...well knowing that we use mostly down cut and compression bits, you VERY QUICKLY realize that you have to take some extra steps to secure your work piece. I'm operating on the principle that it is easier to OVER SECURE the piece than under secure it. The machine isn't going to assist you in keeping it down, it is going to want to pick that piece of and throw it across the room, speaking from recent experience!!
Overall, I love the down cut bits and I'm a firm believer in the compression bits and only use up cut bits when I absolutely have to.
Enjoy!
Nicholas Traub
Principal Graphic Designer
Director of Traveling Exhibitions
Traub Design Associates, Inc.
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