The value of the LT40 hydraulic blade tensioner

[WoodenHead]

I'm not sure if manufacturers other than WoodMizer use a hydraulic blade tensioner, but I have to say that it seems to be a useful feature.  Maybe most of the experienced sawyers here on the forum don't have to pay much attention to it, but I find myself watching the tension gauge quite a bit.  I was sawing some red oak today and noticed that if I wasn't using enough lube, the tension would drop as I cut.  When I increased the lube the tension would climb back up to the "orange" (acceptable) range. 

Question though:  Can it also tell me when my blade is becoming dull?  Can it tell me when I am feeding too fast (or is engine RPM a better indicator of that)? 

[woodmills1]

I hada 40
I have 70
I miss my 40 saw blade hydraulic tensioner
I do not like the 70 bladder air filled  crap

[Dave Shepard]

Listening to the engine will give you great feedback. I don't think the tensioner gauge will let you know when your band is dull, just when it is heating up.

woodmills, I think what you really need is a Wood-Mizer LT62.5. A little of this, a little of that all rolled up into a sawmill. :D

[Magicman]

Without lube to cool the blade, the blade was heating up, stretching, and causing you to loose tension.  This was an indication that your blade had dulled somewhat.  Anytime that I start loosing tension, it is blade changing time.

[POSTON WIDEHEAD]

I watch my gauge all the time. But I let my lumber tell me when my blade is dull. I sawed Red Oak all day Saturday, 3 hours Sunday......which I usually do not do and all day today.
I'm using the 4° blade on this dry Red Oak and getting good service. I keep my gauge on 2800 PSI. Most of the Red Oak has been Mantles and live edge slabs at 16" to 19", 2 1/2 inches thick. I keep my lube wide open in this dry Oak......it helps pulling through a 19" slab. I find my HAPPY speed and stay with it. If I try to exceed my Happy speed, yes....the Psi will drop some. I make adjustments and stay with the right speed.

Using a 10° that has been sharpened 8 or more times and is about to break......yes, the PSI will drop down to around 1800 before it breaks.....a lot of times, I can hear the change in the sound before it breaks.

But keeping a constant eye on your gauge is being a good Sawyer......it can tell you a lot of things.

[woodmills1]

was gonna maka joke but rather say I love my 70 and miss my 40

[woodmills1]

with the 70 air bag it is very interseting
it is fine till it is below 60 psi then junk, but then the compressor needs to show up


I do miss my LT 40 hydraulic

[Dave Shepard]

I remember reading about you and your LT40 in the Wood-Mizer Way, way back when I first got the Wood-Mizer bug. Still have that issue around here somewhere.

[woodmills1]

the 40 really was a one man show

I have been doing a 70 one man show for years, but it wants to be more


Woodmizer LT 70.....  me by my self loadin, stacking, and running got a best of nearly 600 bd ft per hour


wow



the computor
did I say I told it the blade thickness
and I have a sharpener
so there

Ask me a question

[drobertson]

I think anyone with the gauge uses it the same way. For getting started of course, then during the sawing. there have been many times small chunks have found their way to wedge and wear causing heat and loss in tension. Blade still sharp, just an unexpected hiccop. As mentioned, the boards will determine for the most part when the blade is needing  to be changed, the blade tensioner(gauge) is a very useful part of the mill, and in my opinion allows me to focus on other issues without guessing where the blade tension is.   david 

[Chuck White]

I use my tensioner gage all the time and I keep the needle on the yellow/orange line!

Any time your blade heats up you'll lose tension!  Can be caused by lack of lube or the blade getting dull!

[Brucer]

Wide cuts will cause your blades to heat up. So will dry logs. Some species such as WRC have drier heartwood and won't supply enough natural cooling to the blade.

When the tensioner tells you the blade is getting slack, a bit of extra lube will often tighten it up again. Once you've learned what kind of logs/conditions cause the heating, you can anticipate the problem and open up the lube valve before the blade starts to heat up.

[octam1]

having had an older LT40 that used a coil spring for the tensioner, we love having the hydraulic tensioner... much better control of the blade tension and way more ability to run the saw at a faster pace that a snails crawl on wider cuts... we keep a pretty close eye on the tensioner and adjust lube accordingly... we generally change out dull blades based on howour boards are cutting and how things sound...

Charles.

[JustinW_NZ]

Just put a new gauge on my tensioner and rebuilt it since an o-ring failed.
One thing I found it was being more unstable than before after going back on.
Found I had to bleed air out of it a couple of times and then it became more stable again.

Otherwise yes, I like to watch it like a hawk.

Cheers
Justin