Blade Choice and Hook Angle for Different Wood

Sawmillers offer advice on appropriate blades and sharpening specs for use with very hard wood. May 15, 2012

I just got a new, used 98 LT40 super with 40 hp Lombardini engine and am not familiar with what type of blade to use. I want to sharpen and set my own, so not sure if the .055, the thick 1 1/4", is difficult to set and take care of? I think this is the blade Wood-Mizer recommends for the horsepower I have. Any experience with what performs well? I was using an electric 15 hp LT40 and buying 10 degree blades, standard hardwood type, and grinding some of them back to 7 degree for our super hard logs, like stone dead ash and hard maple that I get from tree service guys. This allowed me to saw and sharpen with two different blades, but take care of them without switching cams and whatnot on the sharpener. I don't want too many profiles to monkey with. Is the new 7 degree something to consider?

Forum Responses
(Sawing and Drying Forum)
From contributor M:
I have the exact sawmill that you have. A lot depends on the species that you will mainly saw. I saw predominately SYP with a bit of hardwood thrown in. I use 10 degree blades and use the WM ReSharp service. I know a sawyer that saws predominantly oak and uses 7 degree blades. We are both satisfied with our blade performance.

From contributor S:
I buy mine with a 10* hook and sharpen it to a 4 or 5* hook, as I saw a lot of hard WO and ash. Less hook works better in tough wood. I think you have 19" wheels - a .055 might not give you good blade life. I'd try both .042 and .055, then decide.

From contributor A:
I would use the 0.045 thick blades, as with the 0.055 you will find more blade breakage. The 10 degree blade will give you good service on different woods, but if you do mostly hardwoods, the 7 degree blade will be of benefit. For logs with metal or lots of dirt, the 0.055 will hold up better, but will not take as many sharpenings.

From contributor B:
You should probably pay extra for a mill that's been run a few hours. That just means they have had a chance to break it in some and readjust anything that wore in the first few hours.

We have an LT40 Super with 25 hp electric motor. We saw mostly oak. Sometimes the logs dry before we can get to them. Frozen in winter. We have standardized on Wood-Mizer DoubleHards .045 x 1.25 with 7 degree tooth profile. As contributor A said, the .045s will give more sawing life than the .055s. But the .055s are real nice when sawing the big logs.

We got the WM CBN sharpener and setter last year and Iíve been sharpening our blades. Itís amazing how many re-sharps I have gotten out of the .045 blades. Probably way more than practical.

From the original questioner:
Thanks. Seems like Wood-Mizer thinks the .045 7 degree is the blade to use on this mill as well. I sharpen my own and I don't clutch the motor at the end of cuts, so I'll have a lot more flex time by leaving the blade running. Probably makes the .045 the thing to use. I had them send me some .055 just to see. I do have some super big logs from time to time... Maybe this super hard dead hard maple will saw faster with the .055... who knows. Like to keep things simple, so we'll see if the 7 degree new tooth design gets me the speed and stability that has been talked about.