More about blades

trimguy · January 26, 2021, 03:42:30 PM

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I have read a lot, if not all the threads about blades. When I was using my homemade mill, I was using 8° blades only. They work fine for me. When I bought my wood miser LT 40, I got some 7/47° blades. I also got some 4° blades, that I have not used yet.When

SYP I sometimes get a dip when I go through a knot with the 7° and not the 8°. The problem is the 8° blades leave a lot more sawdust in the cut. The gullet is not as deep on 8° blades to remove sawdust.Also, the 7° seem to dull faster. The picture below is for degree on top 7/47° in the middle 8° on the bottom.I got a cat claw sharpener and setter combo for Christmas. Woo hoo.I have not got it set up yet. My question is, if I grind the gullet deeper on the 8° blades will I have the best of both worlds ??

trimguy · January 26, 2021, 03:47:46 PM

Apparently I cannot get the pictures where I want them. There's one picture with a 7° over top of 8°, the bottom is flush. The 8° actually measures an 1 3/8 from back of blade to tip of tooth. ( it's an 1 1/4 blade ) . The 7° measures an 1 1/4 from the back to the tip of the tooth.Is my cut better because there is more "beam" on the 8°? How much difference would it make to make the gullet deeper to remove more sawdust?

Gere Flewelling · January 26, 2021, 04:19:18 PM

Congratulations on the new Catclaw sharpener and setter. I think if you use the 8* cam and try to make the gullets deeper on the 8* blade, you will end up removing a lot of material from the back of each tooth when the grind rock is lifting/sweeping up out of the gullet. That has been my experience anyway. They might be able to get you another cam. You will need to call Cook's for the specific's.
I have found on the Super sharp blades, that if there is too much set in them (like over .023") they tend to leave a lot of sawdust in the cut. I find I have to resist the urge to run them through the setter prior to measuring the set. I have better luck removing some set prior to sharpening and setting. These are observations I have made with my Cook's set up. Good luck, Santa brought you some excellent equipment.

ladylake · January 26, 2021, 05:22:06 PM

Quote from: trimguy on January 26, 2021, 03:47:46 PM
Apparently I cannot get the pictures where I want them. There's one picture with a 7° over top of 8°, the bottom is flush. The 8° actually measures an 1 3/8 from back of blade to tip of tooth. ( it's an 1 1/4 blade ) . The 7° measures an 1 1/4 from the back to the tip of the tooth.Is my cut better because there is more "beam" on the 8°? How much difference would it make to make the gullet deeper to remove more sawdust?

Yes the shallow gullet blade will saw straighter, no matter if it leaves more sawdust on the cant. Exactly what I've found over the years. When I sharpen I make the gullet shallower on purpose. Steve

dgdrls · January 26, 2021, 08:18:21 PM

What are the teeth set at on the different bands?

D

Percy · January 26, 2021, 09:32:14 PM

Quote from: ladylake on January 26, 2021, 05:22:06 PM
Quote from: trimguy on January 26, 2021, 03:47:46 PM
Apparently I cannot get the pictures where I want them. There's one picture with a 7° over top of 8°, the bottom is flush. The 8° actually measures an 1 3/8 from back of blade to tip of tooth. ( it's an 1 1/4 blade ) . The 7° measures an 1 1/4 from the back to the tip of the tooth.Is my cut better because there is more "beam" on the 8°? How much difference would it make to make the gullet deeper to remove more sawdust?

Yes the shallow gullet blade will saw straighter, no matter if it leaves more sawdust on the cant. Exactly what I've found over the years. When I sharpen I make the gullet shallower on purpose. Steve

With all due respect, I have found the exact opposite over the last 22 years. Perhaps there is a difference in this respect concerning hardwoods and softwoods.

Southside · January 26, 2021, 10:15:00 PM

I actually had the same reaction as Percy. Turbo 7's in SYP leave pretty much nothing on the board and they have a deep gullet.

trimguy · January 26, 2021, 10:50:45 PM

I have not checked the set on the blades yet. I was saying that the 8° blades left a lot more sawdust than 7° blades. But the 8° blades cut flatter through the knots. Looking for flatter cuts with less saw dust.

trimguy · January 26, 2021, 11:20:11 PM

Thanks Gene, I'm excited about it. It has the set that it came with, I haven't checked it yet. Did you find a " set " that you liked ?

ladylake · January 27, 2021, 04:57:27 AM

Over here blades with less set don't leave much sawdust on the cant even shallow gullet blades, more set more sawdust. I really don't care how much sawdust is left, I do care about sawing straight which is why I run shallow gullet blades. Steve

Bruno of NH · January 27, 2021, 04:59:05 PM

I run both the Cooks 8° and the WM t7/39 the 7/39 leaves less sawdust but rougher finish.
Cooks 8° steel is different and pitch won't build up on the band as much. The finish is smoother as well. I like them better in wide hardwood cuts.

trimguy · January 27, 2021, 08:50:36 PM

I finished set up my sharpener tonight and sharpened a couple 8° blades. I did not try to change the gullet depth. If you do not run them through the setter after you sharpen them should you still deburr the blades before you use them ?? I don't think it is necessary, but I have never sharpen blades before, I don't know. I like the sharpener. No experience with any other sharpener though.

dgdrls · January 27, 2021, 09:46:09 PM

Check set/set first, then sharpen.
you want the sharp tooth face perpendicular to the band body

D

Chuck White · January 28, 2021, 08:17:25 AM

Quote from: trimguy on January 27, 2021, 08:50:36 PM
I finished set up my sharpener tonight and sharpened a couple 8° blades. I did not try to change the gullet depth. If you do not run them through the setter after you sharpen them should you still deburr the blades before you use them ?? I don't think it is necessary, but I have never sharpen blades before, I don't know. I like the sharpener. No experience with any other sharpener though.

Personally, I don't see any purpose or benefit in removing the burr at all!
I set my blades, then sharpen, and there's no concern for that burr!

Stephen · January 28, 2021, 09:21:03 AM

Does the 8* leave more sawdust because it cuts faster? For years I sharpened, removed the burr, and set. For the last many years I set, then sharpen, don't worry about the burr. I think I get a better cut too.

trimguy · January 28, 2021, 11:46:33 AM

@Gere Flewelling thanks I like the sharpener. I watched it work and to make the gullet deeper all it would do is make the blade narrower. What set did you come up with that you like ? @ladylake do you think the shallow gullet makes for a flatter cut or because there is more blade width left ? Just trying to learn all of this. @Stephen no I don't think they cut any faster , I think it is because there is not enough room in the gullet for all the sawdust. But I don't know , trying to learn and figure it out. I don't get as much time milling as I would like so it takes a while. Maybe someone smarter can set us on the right path. Thanks everyone.

ladylake · January 28, 2021, 12:48:49 PM

Yes I think a shallow gullet has more blade and shorter teeth with not as much leverage trying to twist it. I never believed the gullet getting full was causing wavy cutting, most could cut pine at high feed rate straight and then switch over to hard wood at way slower feed rates not making near as much sawdust and not cut straight, then blame it on the gullet getting too full. That does not make sense. Just what works for me, I cut a lot of dried out white oak and white ash over here. Steve