10 degree vs. 7 degree blade VS. 4 DEGREE BLADES.

[mikeb1079]

hey peter or marty, can you guys comment on the difference between the 7 and the 4?  i've been running 4's on my 16hp mill with decent results.  just thought maybe there'd be something better?

i look forward to david's experience but i thought maybe you've run them against each other?  my sawming is exclusively hardwoods.  oak, walnut, cherry, birch, etc....

[LeeB]

I have not tried any Wm 7° blades but did try a 7° from another supplier yesterday. It cut good with a great finish but dulled quickly. I suspect it was the log that caused it to dull. The log had been down for a good while alongside the creek and I had to pull it across the creek to get it out. I resharpened the blade on a cooks catclaw at 8°. I put it back on today and was making 12" wide cuts in red oak (same log as I dulled it on). I pushed it harder than I normally do and it seemed to cut better. It came with a .18 set. I would imagine it's at .17 or less after sharpening. I also discovered that my adjustable guide arm was loose and one of the guides was too far back. This may have been causing my blades to break. Hopefully adjusting everthing will make the rest of my blades work better. I ususally run WM 9°, but they are all 8° after the first sharpening.

[ND rancher]

I tried a 7°from another company and just loved how it cut. I was using  10°. There was a big difference all around.I have some WM 4° and 7° coming and hope to try next week.

[Slab Slicer]

I've been sawing all kind of logs with 10 degree blades. (Red Oak, Normay Spruce, Ash, White Pine, Poplar , etc, etc.. I'm using my LT 15 w/ the 18 HP Kohler. Would going to a 7 gegree be too much for my mill to handle. The spruce was the worst if there were knot. I had to slow way down to keep the blade from diving. I'm worried that running that slow would overheat the blade, and in turn, cause it to dull faster. Would waiting for the spruce to freeze, make the 10 degree blades work better? I did break one blade after sawing alot of the spruce also. Can this broken blade be repaired? It broke right at the weld point.

[PC-Urban-Sawyer]

I've been sawing all kind of logs with 10 degree blades. (Red Oak, Normay Spruce, Ash, White Pine, Poplar , etc, etc.. I'm using my LT 15 w/ the 18 HP Kohler. Would going to a 7 gegree be too much for my mill to handle. The spruce was the worst if there were knot. I had to slow way down to keep the blade from diving. I'm worried that running that slow would overheat the blade, and in turn, cause it to dull faster. Would waiting for the spruce to freeze, make the 10 degree blades work better? I did break one blade after sawing alot of the spruce also. Can this broken blade be repaired? It broke right at the weld point.

Well, it is possible to repair a broken blade using a blade welder. Generally it's not done because usually if a blade breaks in one place it's about due to break in several more.

If this is a new blade and broke at the weld, perhaps the blade vendor will replace the blade (assuming blade broke due to a bad weld...) Can't hurt to ask them.

Good Luck and Be Careful!

Herb

[Peter Drouin]

hey peter or marty, can you guys comment on the difference between the 7 and the 4?  i've been running 4's on my 16hp mill with decent results.  just thought maybe there'd be something better?

i look forward to david's experience but i thought maybe you've run them against each other?  my sawming is exclusively hardwoods.  oak, walnut, cherry, birch, etc....

When I had a lt 40 with a 24 h onan I use 1 1/4 x35x10s. When WM came out with 7s I got some but there were 1 1/4x55x7. that 55 cut good on soft wood, but on hard wood the hard wood was to much for the onan, so I use the 10s on soft and 7s on hard wood. but now I have a cat 51h, all I have is 1 1/4x55x7s now. but what has help me is to play with the set.

A new blade has 25 degree set, when I sharpen them I go to 30 degrees,and for me it works on all kinds of trees. but I don;t have sweetgum trees :D :D :D

[taylorsmissbeehaven]

I was very surprised at how well the 7s did for me on my lt15. I was cutting dry poplar and they moved through it much quicker than the 10s I normally use. I have three dry pines on deck right now that will get cut Saturday. Lookin forward to it!Brian

[WDH]

Taylor,

What is the HP on your LT15?

[taylorsmissbeehaven]

I have a kohler 15 hp. so far it has worked out very well for the amount and type of cutting I do. It is a hobby for me that sometimes makes some money. How about yours, and do you have any pros or cons with the 10 vs. 7 vs 4 debate on an lt 15? I'm always interested in what others have learned! Brian

[drobertson]

I think If I had the smaller hp machines, I would try at least one of the 4's just to see for myself. I think I understand the hp issue they claim about running the 4's, but I am thinking if you run the feed at an acceptable feed it should work, just me, Not sure what the gain would be, I just cut some hard pin oak, lightning hit and dead as a door nob, bark completely off and the 7's did real good at the widest, 16" not that wide but wide enough. 

[POSTON WIDEHEAD]

Well.....I learned something today about the 7° blade.  ;D

When it comes to 7° or 10°........when you hit metal, they are all the same.  :D :D

And I'm guessing the 4° is no different when introduced to a galvanized 16 penny nail.  >:(



 

The blade ran South in the cant when the nail was hit.  And I loved that 7° blade.


 

 

[mesquite buckeye]

Well.....I learned something today about the 7° blade.  ;D

When it comes to 7° or 10°........when you hit metal, they are all the same.  :D :D

And I'm guessing the 4° is no different when introduced to a galvanized 16 penny nail.  >:(



 

The blade ran South in the cant when the nail was hit. 


 

 

One day we were cutting a big and not so great mesquite log and the saw caught onto something and jammed. After prying off the cut and backing out, I found iron, started pulling and pulled out a complete chain attached to a leg hold animal trap that had been inside a hollow inside the tree. I'm guessing something got caught and crawled into a hole into the hollow and died there.

[WDH]

David,

That is what you get when you saw that DanG wood.  That stuff is bad  :D.

Taylor,

I have only used the 10 degree blades.  I had a 15 HP Kohler on my LT15 that I used from 2001 to the Fall of 2012, but I upgraded to a 25 HP LT15 a couple of months ago.  I am interested on how it would handle a 7 degree blade.

[MartyParsons]

Hello,
Answer to questions.
The WM 10 degree blade has a 30 degree back angle.
The 4 degree has a 32!degree back angle.  Sorry! I had incorrect back angle.
The 7 degree has a 34 degree back angle
9 degree is 29 degree back angle.
Sorry I don't have the set In each profile in my head but I can get that later.

Yes I would run or recommend the 4 degree in low hp mills and they work well. If you think about what the angle means it is taking less of a bite than a higher hook. So less hook would be a good choice for low hp mills and tough frozen or other woods. The down side to less hook is a slower cutting rate or feed rate.


If you are running the 7 degree and getting wash board or pancake flour on your lumber you need to increase feed rate. If when doing so you change blade speed from running out of power you need a different style of blade.

The profile of the blade is something that every blade manufacture experiments with. The profile = hook angle , back angle, tooth height and gullets depth and set.

We always ask for one blade to cut all but no one that I am aware of has found it. Lots of variables , even the sawiers habits are a big one.

Hope this helps.

Marty

[Slab Slicer]

Thank you Marty. I'll be looking for some of those 7 degree blades when I pick up the trailer unit for my LT 15. Are these something you have in stock? I''ve been cutting with 10 degree blades (18 HP Kohler) with good success, but anything that will make things easier on the engine and myself would be great.  That's if I'm understanding you correctly about the 7's

[Full Circle]

I look forward to hearing how the 4° blades work for you in the seasoned white oak, David.  I was milling some antique flooring from old, white oak beams for a customer with 7's and they worked very well in terms of quality of cut.  The feed rate was slow, but that was to be expected.  They dulled quickly, too, but this stuff was HARD.  I thought that might be a good application to try a 4° after reading some of the guys comments, here on the forum.  Thanks for posting!

[tommone]

Marty, thought the 4° WM blade had a 32° back angle or I have I misread somewhere. Tom

[taylorsmissbeehaven]

WDH, this might not be the proper thread but would love to know about the difference between the 15 and the 25hp. I would give the 7 degree blades a try, I was very impressed. Sounds like the 15hp went the distance for ya! I hope mine will too.Brian

[bandmiller2]

I'am not a stickler for details,and don't think a degree or two ether way has much effect,in fact it pales next to the keenness and proper set of a band.That said my bands are now 6 degrees,I have no problem with the 10's I order, and as I sharpen them they end up with less hook.By all means try different hooks and sets,all that really matters is how the boards come out.Frank C.

[drobertson]

Frank, are you running the Super Sharps?

[Magicman]

Also, the power of suggestion usually affects our opinions.  If you want or need a product to perform better, then it usually will. 

I am not suggesting that a 4°, 7°, or whatever won't perform better in some instances because surely they will and do.  Just that there is not a "magic bullet" that will overcome all of our sawing obstacles, but continuing to look for it can be fun.

[bandmiller2]

Drobertson,I tried a supersharp,a very good band and a smooth finish but no real gain over my standard Timberwolf bands.I would rate supersharps right  up with the better bands. Frank C.

[drobertson]

I have heard this, thanks for the response, I run the Cook's for now, they work for every thing I cut so far, although, some of the older wmz blades I have pulled out have done real well just the same.

[learner]

Spoke to a blade specialist at WM.  They are sending me a 4 & 7.  The difference is they will be .055 thick rather than the .042.  It seems that with the 51 Cat, my feed rate should be higher than what i'm getting.
The blades we are using are the ones reccomended by the original owner.  But He just saws cedar.  Most of the logs we saw are hardwoods though.
So I'm going to try the new blades but the blade specialist couldn't answer One question for me.  Didn't have the figures available at that time.
Normally, the spacing between the guide block and blade is .080-.010.  Does anyone know what it should be with the thicker blade?  I don't want to be pealing metal off anything but I also don't want the blade fluttering.  Can anyone help me with this?

[POSTON WIDEHEAD]

I always gage mine with a business card or take a dollar bill and fold it into. If I can barely slide it between the blade and the block on top and bottom, I'm good to go.