Tension on blade

[Kasba]

Can too much tension on your blade cause it to come off?

[Kingmt]

Yes. It can also cause bearing failure, wheel deforming, & broken blades.

[ladylake]

 Worn v belts will cause that or too much diesel lube, I try not to increase the tension to saw straight as that is hard on everything.  Steve

[Den-Den]

Excessive tension can cause the frame and shafts to deflect enough to foul up the alignment causing the blade to move forward and come off.

[Peter Drouin]

My 40 Supper has no problem with tension. ;D


 

[Chuck White]

Not Me!!!

I run my mill with the needle on the tension gage on the line where the yellow meets the orange, around 2100-2200!

[drobertson]

Not real familiar with your band mill but I would think that too much tension could do that, if its above the designed amount required, something could give way that holds the tracking in line and cause the band to ride off. All you need is enough tension to give you the desired results both quality and efficiency.  Each make has its limits, stay within this and you should be good to go for a long time. 

[WDH]

On my new LT40, blade tension is supposed to be 2800 - 3000 psi. 

[WH_Conley]

I try to keep at 3000 or a bit less. Any more and it is hard on the hydraulic tensioner and bearings.

[ladylake]

 And on the bands.  Steve

[ncsawyer]

On my new LT40, blade tension is supposed to be 2800 - 3000 psi.

Same here.  New LT40 calls for 2,800 to 3,000, but my 94 LT40 called for 2,200 to 2,400.  Don't know why the change in recommendation.   I do know that in all my hours of sawing, I think I have broken only one blade.  I always try to run the recommended PSI.

[Chuck White]

And on the bands.  Steve

And band wheel belts.

[Den-Den]

I agree with everything that has been posted on this thread but would like to point out that pressure on the hydraulic cylinder and tension on the blade are two separate things.  Not all mills use the same size cylinder nor the same size blade.  A hydraulic pressure that works on one brand with a certain blade is not helpful to someone with a different size cylinder or different size blade.

[Dave Shepard]

On my new LT40, blade tension is supposed to be 2800 - 3000 psi.

Same here.  New LT40 calls for 2,800 to 3,000, but my 94 LT40 called for 2,200 to 2,400.  Don't know why the change in recommendation.   I do know that in all my hours of sawing, I think I have broken only one blade.  I always try to run the recommended PSI.

I was told the change was due to WMs continuing research into bands and metallurgy. I run 3,000 psi also.

[Grizzly]

I agree with everything that has been posted on this thread but would like to point out that pressure on the hydraulic cylinder and tension on the blade are two separate things.  Not all mills use the same size cylinder nor the same size blade.  A hydraulic pressure that works on one brand with a certain blade is not helpful to someone with a different size cylinder or different size blade.

Precisely. I run 5000psi on my Logmaster with 30" wheels and 19'1" bands. I can't imagine that other makes and styles would appreciate that. From the factory they recommend 6000psi but due to my northern location and winter temps I lowered it.

[pineywoods]

The manual for my old 95 lt40 might shed a little light on the subject. It has recommendations for 2 different tension settings, depending on the blade. A lower setting for .035 blades, a bit higher for .042. Doesn't mention .045 blades which is what I run exclusively, so I run just a tad more. Maybe the guys who run the tension up near max are running .055 blades. I find that blade tension is not all that critical IF IF IF everything else is up to snuff. I don't like to use increased tension to compensate for other problems...

[Kingmt]

For my mill Cutting Edge told me to run a cheap Chinese caliper out to 6" & clamp it to the slacked blade. Start tensioning the blade until it is stretched .050". I fallowed his instructions & aligned the blade. All seems well for me.

[bandmiller2]

Its my belief too much tension on the band is the biggest  cause of early band breakage along with running dull. It just feels so natural that a really tight band will prevent dives and waves, but alas not so, its a keen edge and proper even set that carries the mail. Frank C.

[kelLOGg]

Its my belief too much tension on the band is the biggest  cause of early band breakage along with running dull. It just feels so natural that a really tight band will prevent dives and waves, but alas not so, its a keen edge and proper even set that carries the mail. Frank C.

Ditto. I have a spring tensioner which I set just to the point of blade flutter. When it enters the log the flutter goes away. If I increase the tension to remove the flutter I get an increased breakage rate.  (Learned this on the Ff)

Bob

[Cutting Edge]

Start tensioning the blade until it is stretched .050".

This measurement should be 0.005" or Five Thousandths of an inch.

Not all mills are built to take this much tension due to manufacturing, materials, components, etc.  I've serviced mills that could only SAFELY tension a blade to about 17,000 lbs. of strain.  Any higher than that and the main beam of the mill began to deflect/deform.  In most of those cases, the manufacturer's "setting" was pretty close to what my blade tension/strain gauge was reading.

Anyone using the method mentioned above, be smart about it.  Have the right tools for the job.  Not all mills are built to handle the tension that some blade manufacturers recommend. 

[Kingmt]

Thanks again Cutting Edge. That seems to be twice I made the same mistake.