HP for 4° blades?

D6c · March 01, 2018, 02:32:08 PM

I was wondering how more power is required to use 4° blades as opposed to 7 or 10's?
I have a 20 hp Onan and am interested in your experience with lower hp mills and 4° blades.

Thinking I'd like to try out bi-metal while I'm experimenting too....I know bi-metal is all I use anymore on a metal cutting saw.

Kbeitz · March 01, 2018, 02:44:30 PM

I was told that 4% is the blade to use for low hp.

D6c · March 01, 2018, 02:47:40 PM

Maybe my assumption is wrong....I figured the low tooth angle would pull harder.

Kbeitz · March 01, 2018, 02:50:04 PM

It's the only blades I use... 13hp Honda...

firefighter ontheside · March 01, 2018, 03:08:31 PM

I have discovered that 4° would be better for the lower HP from what I've read. I inherited an LT15 with 15 HP and all the blades I got with it are 10°. It makes me wonder what it would be like with 4°.

Skipper11A · March 01, 2018, 03:13:42 PM

20hp is plenty of power. Rember, you're using a 4* blade to make flat cuts in extremely hard or frozen wood. Your cutting speed will be slow so that the blade doesn't dive or rise in the cut. Horsepower is pretty irrelevant unless you're sawing extremely wide boards or your trying to jam the blade into softer woods as fast as it will go.

alanh · March 01, 2018, 03:23:40 PM

I have a lt15 with the 13? hp kohler, all I use is 4 degree, they work fine

Pabene · March 01, 2018, 03:43:30 PM

About 4° hook angle blades.

I have learned that, for the same specified wood, it works like this:
A blade with a hook angle of 10° will be "neutral" and cut straight.
A blade with a hook angle of 13° will "feed it self" in the same wood and will have a tendency to go up and stay higher in the cut.
A blade with a hook angle so steep as 4° will have a tendency to dive and stay low in the cut.
For other kind of wood the behavior trend would be the same but the "neutral" hook angle can be different.
Based on this I think it is good to be able to grind your own blade to the best hook angle, for the wood you are going saw.
I am also convinced it will shorten the life for the blade to "press feed" it with to steep (less than 4°-6°) hook angle most of the time.

SawyerTed · March 01, 2018, 04:03:54 PM

I've got a LT35 with 25 hp Kohler. When I went for training on the mill, I spent about 45 minutes with the Resharp guy at Woodmizer Carolinas. His explaination - or what I understood- was a 10 degree blade cuts best in softwood and a 4 degree blade cuts best in hardwoods. A 4 degree blade will handle softwood fine so no need necessarily to switch back and forth between blades. He recommended that I use 4 degree blades exclusively since I will cut both with a good amount of white and red oak.

According to the Resharp guy, 7 degree turbos are best used on sawmills with greater than 25 hp.

I've milled about 15 or so white oak logs up to 28" diameter and 10' long. The 4 degree blades have worked very well.

D6c · March 01, 2018, 04:28:26 PM

4° it is then....need to order a box as I'm getting about out and will have quite a bit of sawing when the mud dries up enough.

D6c · March 01, 2018, 04:39:36 PM

Bummer....Looks like the only blade WM has in 4° is the Double-Hard. I was seriously considering going to bi-metal.

Is that the blade all you 4° guys are using or is there another brand out there you like?....maybe in a bi-metal

starmac · March 01, 2018, 04:44:53 PM

You might try contacting them in person, ot everything is always listed.
You may also get in touch with cutting edge I want to say Richard is the one to talk to to see what kasco has to offer.

Kbeitz · March 01, 2018, 05:02:47 PM

I get mine from kasco...

starmac · March 01, 2018, 05:28:58 PM

WHAT, you don't get your blades out of the junkyard, I'm flabbergasted.

SawyerTed · March 01, 2018, 05:34:56 PM

Mine are the 4 degree double hard.

Bimetal are almost 3 times the cost. Others will have to say whether there is savings in using them.

Kbeitz · March 01, 2018, 05:51:13 PM

Quote from: starmac on March 01, 2018, 05:28:58 PM
WHAT, you don't get your blades out of the junkyard, I'm flabbergasted.

That's funny because my first blades did come from the junkyard... I cut them down to fit my mill and silver soldered them to fit my mill. I could still get blades there but I'm finding I don't have the time to full with them. Last year I bet I got two hundred new blades from the yard.

WV Sawmiller · March 01, 2018, 06:05:26 PM

4 degree DH are my preferred blades and the only one I would take if I could only take one blade on a remote job with me. I'm using a 25 hp Kohler engine. I'm no expert but I understand the 4 degree cuts a smaller chip hence requires less hp and cuts straighter through hard wood including hard knots in softwoods.

I have not tried the other types of blades such as bimetal or such.

Crossroads · March 01, 2018, 06:09:03 PM

When I bought the old lt30 it came with 9's and 10's. I didn't like how the cut fir, so I switched to the 4's for cutting everything except cedar. The 18 horse pull them fine. Now with the LT40 and 28 hp, I'm still running the 4's almost exclusively.

dgdrls · March 01, 2018, 10:14:55 PM

Quote from: D6c on March 01, 2018, 04:28:26 PM
4° it is then....need to order a box as I'm getting about out and will have quite a bit of sawing when the mud dries up enough.

What will you be sawing predominantly?

Let that guide your choice,

D

Southside · March 02, 2018, 12:20:59 AM

Quote from: SawyerTed on March 01, 2018, 04:03:54 PM
I've got a LT35 with 25 hp Kohler. When I went for training on the mill, I spent about 45 minutes with the Resharp guy at Woodmizer Carolinas. His explaination - or what I understood- was a 10 degree blade cuts best in softwood and a 4 degree blade cuts best in hardwoods. A 4 degree blade will handle softwood fine so no need necessarily to switch back and forth between blades. He recommended that I use 4 degree blades exclusively since I will cut both with a good amount of white and red oak.

According to the Resharp guy, 7 degree turbos are best used on sawmills with greater than 25 hp.

I've milled about 15 or so white oak logs up to 28" diameter and 10' long. The 4 degree blades have worked very well.

I am going to go against the grain here. Yes WM says the turbo is designed for use over 25 HP but of my 70 or so bands 60 or more are turbos these days and as the 10's die off they are replaced with turbos. All on a 25hp LT35.

Ianab · March 02, 2018, 12:37:46 AM

Quote from: Southside logger on March 02, 2018, 12:20:59 AMI am going to go against the grain here. Yes WM says the turbo is designed for use over 25 HP but of my 70 or so bands 60 or more are turbos these days and as the 10's die off they are replaced with turbos. All on a 25hp LT35.

Likely depends what you are cutting. In regular hardwoods, and not maxing out the cut width, the 7s will probably work fine on your mill, and should cut slightly faster than the 4deg ones. Get into some wide cuts on some real gnarly wood like Sheoak or Live Oak, they maybe wont be as happy.

"Best" blade depends on YOUR mill, and what YOU are cutting.

Southside · March 02, 2018, 07:45:35 AM

We don't have Sheoak or Liveoak around here, but we have hickory. I don't know exactly how wide the largest hickory is that I have sawn but safe to say somewhere in the upper teens. Earlier this week I had a SYP that filled the throat, had to gun barrel the log and even then managed to hang up once or twice, so I do get some wide stuff.

My point is that those bands will work where they were not designed to work. I am pretty happy they were recommended to me by a Wood Mizer dealer who thinks outside of the box.