Table Saw Blade Question

[jfmyer]

I have a DeWalt DW746 table saw that has a motor rated a 1 3/4 hp operating on a 110 volt circuit. I have read some recommendations that thin kerf blades should be used with similar set ups. In the past have used full kerf blades and thin kerf blades, and have not noticed that much difference. I am getting ready to purchase a new rip blade and once again I am wondering whether I should purchase a full or thin kerf. Any recommendations?

[thewizzard]

I run a 12 year old Craftsman contractor style saw probably rated at less than 2 HP and its never seen anything other than a standard blade. I've never bogged down the motor. I'm sure if you insist on trying to feed wood into the saw at a sprinters pace you probably would see a difference with the thin blade but unless you are running a production shop just take an extra 5 - 10 seconds to make your cut and you will never notice the difference.

[Wild Turkey]

How thick and how hard is the wood are you planning to rip???

When I had a contractor's saw I used thin kerf most of the time but the one time I needed to rip some thick stuff I could tell the difference.

Cutting full depth put that saw to work. I could have done half/half cuts but didn't want to worry about lining the kerfs up.

[jteneyck]

Of course it takes less power to drive a thin kerf blade than a full kerf one, by the ratio of their kerf. That said, 1-3/4 HP is plenty of power to run a full kerf blade as long as it's sharp. My Unisaw only has a 1.5 HP motor and it cuts fine with a full kerf blade, even in 2" oak or maple. Production speed? Of course not, but it cuts fine.

John

[knotscott]

Think of this way. A 1/8" full kerf blade is 33% wider than a 3/32" TK blade, so it takes 33% more material, produces 33% more dust, and poses more resistance. If the blades are sharp, and the wood isn't thick or tough to cut, it doesn't make much differences, but as you get into thicker more dense materials, the saw will definitely have an easier time spinning the TK blade. There are some really good TK rippers too....Infinity 010-124, Freud LU87, Forrest 20T, CMT, Irwin Marples, Tenryu, Amana. A good TK blade can rival the cut quality of a good full kerf blade, so if you're splitter is compatible with the TK, I'd definitely lean in that direction.

[The Famous Grouse]

knotscott said:

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Think of this way. A 1/8" full kerf blade is 33% wider than a 3/32" TK blade, so it takes 33% more material, produces 33% more dust, and poses more resistance. If the blades are sharp, and the wood isn't thick or tough to cut, it doesn't make much differences, but as you get into thicker more dense materials, the saw will definitely have an easier time spinning the TK blade. There are some really good TK rippers too....Infinity 010-124, Freud LU87, Forrest 20T, CMT, Irwin Marples, Tenryu, Amana. A good TK blade can rival the cut quality of a good full kerf blade, so if you're splitter is compatible with the TK, I'd definitely lean in that direction.

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My point exactly. To me, there is no benefit in running a full kerf blade, so I don't do it. It's easier on the saw to use thin kerf and it wastes less lumber.

I have a small contractor saw, so to take advantage of ever ounce of HP, I run a thin kerf. I get good cuts and the are square and flat with no burn. What else is there?

Back in the bad old days there were more clear benefits to running full kerf, but like everything else the quality of the TK blades has moved way, way up. As has been pointed out in another thread recently, when you adjust prices for inflation, these ARE the good old day when it comes to high quality tools relative to their prices.

My dad built his own table saw from a kit back in the 1960s because it was the only saw he could afford. The blade cost him almost as much as the motor for the saw back then. If I adjust his total outlay for that home-built saw for inflation over 40 years, he paid almost twice for that saw what I paid for my Rigid contractor saw.

Grouse

[jteneyck]

As you both said, there are many good TK blades available today at very reasonable cost. I use a cheap Diablo much of the time for utility work. But you can't defy mechanics and a full kerf blade will have less deflection than a thin kerf one and give you smoother cuts. This may not be noticeable when you are making a full cut with wood on both sides of the blade, but it often is when you are doing a skim or trim cut. The thinner plate just can't resist the bending force the wood wants to put on it as well as the thicker plate on a full kerf blade, especially if the blade is just a little dull.

When it really matters I reach for a full kerf blade.

John