Blade Tension when not using mill

[Cutting Edge]

I let mine off at the end of the day. It might be tomorrow, or next month before I saw again. Okra I bought a pawn shop torque wrench to solve tightness problem. That was after a major problem of a broken shaft. The biggest part of the problem  was figuring out what the problem was.       

Excellent/Simple solution for us with non-hydro tensioners!!!   8)  That would take all the guess work and "fluttering" outta the equation...I will be adding this to the mill tools for sure!!  Just have to remember to back off the torque wrench now   :

[Brucer]

I know it is common practice to back off the tension on the blade when done sawing for the day. But I don't know why. In all these posts in this thread there is not one with a good reason why we do it. ...

Here's the one you missed ;D.

... In these parts the temperature change from early morning to afternoon will cause the fluid in the tensioner to expand. I've seen the tension go right off the gauge when I forgot to back off the tension during lunch.

To give you an idea of what can happen, my friend John bought a new hydraulic Wood-Mizer 3 years ago. A few days after he fired it up he noticed the blade was losing tension. Wood-Mizer told him to check the fluid level in the tensioner -- it was full. They had him try a couple of other troubleshooting tricks -- nothing.

Finally they told him to just keep tightening it. There must be a fluid leak somewhere and it would eventually show up. Well John was sawing and the pressure kept falling off so he just kept winding up the adjuster. Suddenly in the middle of a cut there was a loud bang and fluid sprayed straight up in the air from the tensioner. It turned out the guage was faulty and he had the pressure up around 4500 PSI. It blew the top right off the guage.

The point here is that rising air temperature or direct sunlight pushes the pressure up 'till you're off the guage, you really don't know how high it's gone.

[ely]

i take the pressure off my norwood each day or if i stop for lunch.
i also turn of the water and run the band until dry before i let it off.
i have been squirting oil on the blade guides too after the bands dries.seems to help the bearings.

[Okrafarmer]

I oil the bearings. They're too expensive not to.  >:(

[Chuck White]

It's also been said that in hot weather, that if you don't back the tension off when shutting down, that due to the heat, the band could snap.

[tcsmpsi]

I release all tension on my band at the end of the sawing day.  The torque wrench (for those to whom it might apply) works if you use the same type of blade.  Different bands work most efficiently with different tensions.

[bandmiller2]

When I'am done sawing at the end of the day I usally remove the band for sharpening and install a sharp one might as well leave it slack til the next running.Prehaps theirs no real damage from leaving the band tensioned but it can't help it, bearings,springs and belts. Frank C.

[fat olde elf]

 Cook's manual says to detension at the end of the day.  I rarely forget. Not worried about flatttening any belts on the mill as I have solid steel band wheels. Just trying to follow directions.........Say your prayers

[starrtraveler]

Cutterboy,

See the link I posted from Suffolk Machine in this thread,

Item 3 page 6 of the online catalog answer's your question(s).

Best DGDrls

Just printing out your reference to Suffolks recommendations for de-tensioning blades after cutting.
ALWAYS DETENSION YOUR BANDS
When you are done cutting for the day, take the tension off your blade. Band saw blades, when warmed up from cutting, always stretch; and upon cooling shrink by tens of thousandths of an inch each cooling period. Therefore, blades, when left on the saw over tension themselves and leave the memory of the two wheels in the steel of the band, which will cause cracking in the gullet. When you leave the band on your saw under tension, not only do you distort the crown and flatten out the tires (which makes them very hard), but you also place undue stress on your bearings and shafts. Believe it or not; you can, and will damage your wheel geometry sooner or later and considerably shorten bearing life. You are also crushing your tires or V-belts.

Figured this would be a nice link to throw in: http://www.suffolkmachinery.com/six-rules-of-sawing/

[Knute]

I have had my LT28 for 18 months and have never released the tension except when changing blades. Have never had any problems, but maybe should start to release when not in use. I don't remember seeing anything in the instructions regarding this, but I could have missed it.

[cutterboy]

Cutterboy,

See the link I posted from Suffolk Machine in this thread,

Item 3 page 6 of the online catalog answer's your question(s).

Best DGDrls

Thanks dgdrls, that was very interesting. I guess I'll be more careful about backing of tension.

[cutterboy]

Brucer, my Norwood has a different tensioner than your Woodmiser. There's no fluid in it. It has a large spring. However, thanks for your post..... there are so many woodmiser owners out there.

Starrtravler, thanks for posting the info that dgdrls brought to our attention. There is good information in there.