In a RAS the negative rake has the effect of pushing the work downwards and backwards, thus pinning it against the table and back fence, so the reason has little to do with finish, per se, however the negative rake makes a less aggressive entry/exit from the workpiece and therefore produces less chip-out, a major bugbear with melamine/laminate coated workpieces.PJ":knivs26p said:
Transferring a negative rake blade onto a table saw will confer the advantages of minimised chip-out enjoyed by the RAS, however it will be a the cost of a much increased tendency of the workpiece to climb the blade and to kickback, so if using a negative rake blade on a table saw extra caution is advised and there is a need to keep the workpiece firmly pressed down to the saw table at all times. It is therefore a technique which needs to be used with care.
Agreed, standard triple chip has a longer life between sharpenings, more sharpenings in lifetime but really requires a pre-scorer to work to maximum effectiveness, i.e. speed of cutting and quality/longevity of good cut - one reason almost all commercial panel saws use the system (cost/performance benefits). I tried hollow grind triple chip a few years back and it really wasn't that much better than a standard triple chip to warrant paying the premium. The negative rake trick was one I picked up from Keith Smith (Woodsmith) and is a lower cost way of clean-sawing on even relatively small table saws, providing you're careful. I've used it a number of times on installations where my "table saw" is a DW flip-over saw and all I can say is that the results are pretty goodivan":knivs26p said:
As to blades, I'm not that impressed with CMT and much prefer either Omas or Freud given a choice - but then I mainly use Bennett (made in Sheffield), Leitz, Freud and Omas at the moment, so maybe it's just bias on my part :roll: .
Scrit
