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Woodmizer lt40 blades

Started by POSTON WIDEHEAD, February 21, 2011, 08:49:17 PM

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POSTON WIDEHEAD

How many board feet of lumber should I mill before I should change blades? I saw mostly pine and red oak and some ash. Thanks.
The older I get I wish my body could Re-Gen.

pineywoods

Change 'em when they get dull. Don't matter how many board feet. Lots of variables. Oak dulls a blade quicker than pine, bark dulls blades, dirt or sand on the log dulls blades. You can't assume that all blades start out with the same sharpness, especially if you do your own. What you need to do is learn to tell when a blade is starting to dull, and mostly that comes with experience. I have changed blades after 200 bf, also sawed all day long 700-900 bf on one blade. Wish I could give you a more definite answer but there's just too many things that affect how soon a blade dulls.
1995 Wood Mizer LT 40, Liquid cooled kawasaki,homebuilt hydraulics. Homebuilt solar dry kiln.  Woodmaster 718 planner, Kubota M4700 with homemade forks and winch, stihl  028, 029, Ms390
100k bd ft club.Charter member of The Grumpy old Men

Knute

I have 1050 bd. ft. on the blade I am now using and it still saws fine. I expect I may get another 200 bd. ft. before changing. I have been very careful to avoid any dirt. This is sawing red oak.

POSTON WIDEHEAD

Thanks a bunch. I have a debarker and that's why I asked. But your probably right....it comes with experience.
The older I get I wish my body could Re-Gen.

MartyParsons

We have always told customers 500 to 800 bd/ft. Lots of veriables to this statement like everyone else said.
If you put the blade on after sharpening and it breakes in the gullett you know you have gone beyond the flex life of the blade. When ReSharp grinds the blade we remove about .020 and lengthen the flex life, remove the crack. If the blade was ran to long even if it was still cutting the crack in the gullett is over the .020 and the blade will keep cracking  after sharpening and break.  :(
Thicker blade usually refered as beam strength cutts better for short terms, thinner blades flex longer but have a lower beam strength. IMO the .045 works the best, higher production mills use the .055. We could keep adding to this but this is more than you asked for.
Hope this helps.
Marty
"A pessimist sees difficulty in every opportunity; an optimist sees opportunity in every difficulty." -Winston Churchill

Magicman

I generally get between 500 to 1000 bf per blade sawing SYP.  The less knotty the logs are, the more bf.  Last week, I sawed 1200 bf with one blade.  Oak will generally be less.  I saw very little Ash.

You can just feel it when the blade begins to dull, and also hear the engine speed.
Knothole Sawmill, LLC     '98 Wood-Mizer LT40SuperHydraulic   WM Million BF Club Member   WM Pro Sawyer Network

It's Weird being the Same Age as Old People

Never allow your "need" to make money to exceed your "desire" to provide quality service.....The Magicman

kderby

When the blade starts walking over the knots, the best fix is a sharp blade.  Quality control will convince you pretty quick that a new blade is in order. 

This is also a good place to mention that blades are not a huge factor in the price of lumber.  Much better to spend a few more pennies and have nice lumber produced at a good pace.  Forcing the mill to keep a dull blade moving is hard on everything, sawyer included.

IMHO ;D

KDerby

Chuck White

I saw mostly White Pine and average between 750 and 1000 board feet.

However, once in a while I put a new band on and only get a couple of hundred board feet! 

Whenever you hear the engine raise in rpm or you have to increase your feed speed, it's a sign that your blade is probably getting dull!
~Chuck~  Cooks Cat Claw sharpener and single tooth setter.  2018 Chevy Silverado and 2021 Subaru Ascent.
With basic mechanical skills and the ability to read you can maintain a Woodmizer  LT40!

Magicman

Quote from: kderby on February 21, 2011, 10:49:35 PM
This is also a good place to mention that blades are not a huge factor in the price of lumber.  Much better to spend a few more pennies and have nice lumber produced at a good pace.  Forcing the mill to keep a dull blade moving is hard on everything, sawyer included. 

Thank you kderby for this very important statement.  It doesn't matter whether you resharpen or use a resharpening service, the blade cost is a very minimum expense when sawing.  Using or attempting to use a dull blade produces poor quality lumber and is false economy.
Knothole Sawmill, LLC     '98 Wood-Mizer LT40SuperHydraulic   WM Million BF Club Member   WM Pro Sawyer Network

It's Weird being the Same Age as Old People

Never allow your "need" to make money to exceed your "desire" to provide quality service.....The Magicman

Bodger

Good choice of words "false economy".  There are alot of things that fall under that heading...spending $50 worth of time to fix a $16 part.  While blade cost is a small part of sawing expense, blade problems seem to be a major part of sawing problems.  Better off to pull of a blade, mark it and re-visit the sharpener and setter than to try and wade through poor sawing.
Work's fine for killing time but it's a shaky way to make a living.

Magicman

Plus, producing an even marginally quality product will eliminate future business with that customer.

Many times, I've had customers ask why I was changing a band.  I would show him a board, and say "because of this".  He would say "I wouldn't have noticed, or that it didn't matter".

My answer is "well I noticed, and it mattered to me".   Customers do notice that, and he will be a repeat customer.
Knothole Sawmill, LLC     '98 Wood-Mizer LT40SuperHydraulic   WM Million BF Club Member   WM Pro Sawyer Network

It's Weird being the Same Age as Old People

Never allow your "need" to make money to exceed your "desire" to provide quality service.....The Magicman

Chuck White

Quote from: Magicman on February 22, 2011, 11:42:45 AM
Plus, producing an even marginally quality product will eliminate future business with that customer.

Many times, I've had customers ask why I was changing a band.  I would show him a board, and say "because of this".  He would say "I wouldn't have noticed, or that it didn't matter".

My answer is "well I noticed, and it mattered to me".   Customers do notice that, and he will be a repeat customer.

Well stated MM.

My feelings exactly!  ;)
~Chuck~  Cooks Cat Claw sharpener and single tooth setter.  2018 Chevy Silverado and 2021 Subaru Ascent.
With basic mechanical skills and the ability to read you can maintain a Woodmizer  LT40!

Peter Drouin

Well said MM .I do the same. and can see real well on the chair. ( up close)  ;) ;) ;D
A&P saw Mill LLC.
45' of Wood Mizer, cutting since 1987.
License NH softwood grader.

Bandmill Bandit

Everything that has been said is but a part of the tuning and honing of each sawyers connection with the mill and the feel of the mill through his fingers on the controls. Each sawmill is different. Listen carefully. Feel the caress of the sawmill to log. Watch the beautiful lines of the cut wood.  When the sawmill asks for a new blade don't ignore it.

Forgot to mention the song of the band. The tone begins to go flat with each cut. There is a harmony between the whine of the band and the growl of the engine. When the harmony is gone your ear will know that the song of the mill is no longer music.



 
Skilled Master Sawyer. "Skilled labour don't come cheap. Cheap labour dont come skilled!
2018 F150 FX4, Husqvarna 340, 2 Logright 36 inch cant hooks and a bunch of stuff I built myself

Peter Drouin

A&P saw Mill LLC.
45' of Wood Mizer, cutting since 1987.
License NH softwood grader.

POSTON WIDEHEAD

All jokes aside.....I have learned a lot from all your answers. Great info....thanks! David
The older I get I wish my body could Re-Gen.

Jim_Rogers

Other tell tale signs of a dull blade:

The blade drops down when you exit the log.
The blade rises up when you exit the log.
You can hear the blade rubbing the guide blocks (if you have them).
You can see the blade guide rollers stop turning, cause the blade has shifted away from the roller.
The lumber is wavy.
As mentioned, the blade walks up over a knot.
You have to turn the feed knob more to go the same speed, you're pushing harder.
Sawdust is real fine.
As mentioned the engine works harder, if you have tachometer the rpms are down.

Learn to read the lumber, log, engine speed, and blade.

Have fun..
Jim Rogers
Whatever you do, have fun doing it!
Woodmizer 1994 LT30HDG24 with 6' Bed Extension

ely

what jim said, i know if i watch my sawdust exit the log i can tell when they band is going dull.it tells me if the set is correct too. i also check the rpm and listen to the engine.

Daniel

I have learnt something about signs of blades geting dull. Further, kindly help me on how i can fix the problem of having saw blades breaking very often. My LT40 is quite new, worked fine for two months and then this problem started. Plz advise. Rgda Daniel.

ladylake

 

Don't forget the sound of the blade, if it doesn't sound right it's cutting crooked or is dull.   Steve
Timberking B20  18000  hours +  Case75xt grapple + forks+8" snow bucket + dirt bucket   770 Oliver   Lots(too many) of chainsaws, Like the Echo saws and the Stihl and Husky     W5  Case loader   1  trailers  Wright sharpener     Suffolk  setter Volvo MCT125c skid loader

zopi

Steve beat me to it...the song of the blade goes flat...hit a bullet the other day...whole tune changed...well...aside from the ping when I hit it...sawed a twenty two into an eleventy eleven...
Got Wood?
LT-15G GO chassis added.
WM sharpener and setter
And lots of junk.

Chuck White

Zopi, I've sawn a few bullets, both cast or swaged and copper jacketed and when the blade exited the end of the log, I shut down and rotated the blade by hand and just took my knife and picked the lead off of the teeth then went back to sawing.

Seems soft metals don't do much for significant damage to the sharpness or set of the teeth.
~Chuck~  Cooks Cat Claw sharpener and single tooth setter.  2018 Chevy Silverado and 2021 Subaru Ascent.
With basic mechanical skills and the ability to read you can maintain a Woodmizer  LT40!

Bandmill Bandit

All of the above is good advice.
One other thing to add that I have learned;

When I push the blade that is still "cutting fine" instead of changing it out based on many of the above conditions I end up with the blade I do that with failing a lot sooner and by failing I mean breaking. I think it is the extra heat and stress of pushing an almost sharp blade has the most significant effect on band life. 2 less sharpenings per band is expensive no mater how you look at it even with band cost as reasonable as it is. 

Less stress on other components as well especially the band guides.
Skilled Master Sawyer. "Skilled labour don't come cheap. Cheap labour dont come skilled!
2018 F150 FX4, Husqvarna 340, 2 Logright 36 inch cant hooks and a bunch of stuff I built myself

4x4American

Quote from: Bandmill Bandit on February 22, 2011, 05:36:23 PM
Everything that has been said is but a part of the tuning and honing of each sawyers connection with the mill and the feel of the mill through his fingers on the controls. Each sawmill is different. Listen carefully. Feel the caress of the sawmill to log. Watch the beautiful lines of the cut wood.  When the sawmill asks for a new blade don't ignore it.

Forgot to mention the song of the band. The tone begins to go flat with each cut. There is a harmony between the whine of the band and the growl of the engine. When the harmony is gone your ear will know that the song of the mill is no longer music.



 


This is great!
Boy, back in my day..

POSTON WIDEHEAD

This is one of the first threads I started when I bought my LT 40 and joined the forum.
I didn't realize how much fun it was to re-read these old threads.  :)

Thanks 4x4 for bringing it back up.
The older I get I wish my body could Re-Gen.

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