The Forestry Forum

General Forestry => Sawmills and Milling => Topic started by: alecs on May 10, 2022, 05:58:37 PM

Title: Loosening blade tension when saw not in use
Post by: alecs on May 10, 2022, 05:58:37 PM
I am the owner of a new Woodland Mills HM130.  In the manual, it says you should let off the blade tension when the saw is not in use to avoid flat spots in the belts (tires) that the blade rides on.  Maybe this is a silly question, but what are your opinions on how long of a time qualifies as "not in use"?

Obviously you are not going to loosen the tension between cuts or between logs in a given cutting session.  But do you loosen the tension when you are done for the day if you are going to saw the next day?  Or only if you are not going to use the the saw for weeks at a time?  

I have an old Ford truck with bias ply tires and it gets flat spots when it sits for a while.  But after a mile or two of driving, they go away.  Is this the same thing with the mill?  Or does it permanently ruin the belts?

Just trying to figure out how hard I have to try to develop this habit!

Thanks
Title: Re: Loosening blade tension when saw not in use
Post by: TroyC on May 10, 2022, 06:05:57 PM
I loosen mine if I stop for lunch. Only takes 10-15 seconds. Just remember to tighten before sawing again. Definitely loosen overnight.
Title: Re: Loosening blade tension when saw not in use
Post by: Oddman on May 10, 2022, 06:06:44 PM
Personally if I shut the engine off then I generally loosen the band. Maybe not every time but pretty close. A band that is warm from sawing will shrink slightly while cooling and theoretically tighten up as a result, which is hard on the band, the belts, and the bearings of the mill. Can't remember if I read that on the forum here or in my owners manual but it makes sense to me.
Title: Re: Loosening blade tension when saw not in use
Post by: Old Greenhorn on May 10, 2022, 06:09:49 PM
End of the day is fine. It's not just the wheels, it the blade too. No need to keep it under that much tension while just sitting. It's part of my end of day shut down. Log stops full up, clamp fully retracted, lube tank off, blade tension off, blow off the mill bed, oil the chains and mill rails, fill out my tally sheet.
Title: Re: Loosening blade tension when saw not in use
Post by: WV Sawmiller on May 10, 2022, 06:20:21 PM
   I'm with Troy and Tom. I try to loosen it any time I don't plan to run it within the next 30 minutes or so but for me it is simply flipping a handle. I confess I forgot and left it under tension recently for over a week.

   I used to remove the blade at the end of the day but recently I started leaving the blade on here at home because I often need to run make just a cut or two. I do not leave the blade on at a customer site unless I am there so if I leave the mill overnight the blade comes home with me.
Title: Re: Loosening blade tension when saw not in use
Post by: Chuck White on May 10, 2022, 08:39:07 PM
I always loosened the blade tension when we broke for lunch.

At the end of the day, I always REMOVED the blade, if the band is left on the mill more than a couple hours, it will develop stains wherever it contacts the bandwheels or the rollers.

I used to go through three bands on an average day, and all three got reset and resharpened.

Title: Re: Loosening blade tension when saw not in use
Post by: RAYAR on May 10, 2022, 09:14:20 PM
Release tension when done for the day or if there's going to be a good length of time of not sawing during the day.
Title: Re: Loosening blade tension when saw not in use
Post by: Larry on May 10, 2022, 09:16:52 PM
I let tension off at the end of the day just because the blade is dull and needs to be sharpened.

In realty I don't think it matters.  I have four shop bandsaws and never take the tension off of them.  One is a 1947 model so I bet the tension has been on it for 74 years now.
Title: Re: Loosening blade tension when saw not in use
Post by: Peter Drouin on May 11, 2022, 06:37:25 AM
At the end of the day too. But like what Larry said is true too.
Title: Re: Loosening blade tension when saw not in use
Post by: ladylake on May 11, 2022, 06:55:10 AM
 
 I loosen mine when it's time to change a band.   Steve
Title: Re: Loosening blade tension when saw not in use
Post by: moodnacreek on May 11, 2022, 07:03:32 AM
If you ever go into a band sawmill that is not sawing the top wheel is dropped.
Title: Re: Loosening blade tension when saw not in use
Post by: Magicman on May 11, 2022, 07:35:26 AM
Quote from: Chuck White on May 10, 2022, 08:39:07 PM
I always loosened the blade tension when we broke for lunch.

At the end of the day, I always REMOVED the blade, if the band is left on the mill more than a couple hours, it will develop stains wherever it contacts the bandwheels or the rollers.
I am 100% with Chuck.  Loosen at lunch time and removed at the end of the sawing day. 
I also use the leaf blower at the end of the sawing day.  There is no substitute for proper maintenance and good housekeeping. 
Title: Re: Loosening blade tension when saw not in use
Post by: firefighter ontheside on May 11, 2022, 07:38:00 AM
I always mean to de-tension at the end of each day with my sawmill and my 17" bandsaw.  I often forget and leave the bandsaw tensioned for long periods of time.  Only once have I forgotten to de-tension the sawmill.  Of course I had no ill effects with either one.
Title: Re: Loosening blade tension when saw not in use
Post by: alecs on May 11, 2022, 07:53:42 AM
Thanks for the feedback.  I went out and loosened the band last night after reading the replies!
Title: Re: Loosening blade tension when saw not in use
Post by: Jim_Rogers on May 11, 2022, 10:15:47 AM
Quote from: firefighter ontheside on May 11, 2022, 07:38:00 AM
I always mean to de-tension at the end of each day with my sawmill and my 17" bandsaw.  I often forget and leave the bandsaw tensioned for long periods of time.  Only once have I forgotten to de-tension the sawmill.  Of course I had no ill effects with either one.
I student showed me a simple trick to remember to tension your bandsaw blade on a shop bandsaw. She made a note on a piece of cardboard that said: "tension blade before starting". And she put a slice in it so that it fit around the bandsaw blade on the table.
You had to move the note in order to use the saw to cut anything. So, you would tension the blade, cut your piece, and then loosen the blade and replace the note.
It worked for me.
Jim Rogers
Title: Re: Loosening blade tension when saw not in use
Post by: Magicman on May 11, 2022, 01:33:49 PM
I hang my leather apron on the tension knob at lunch time. 
Title: Re: Loosening blade tension when saw not in use
Post by: firefighter ontheside on May 11, 2022, 07:30:59 PM
Yeah, turning on the saw with the blade not under tension is a bad idea.  Don't ask me how I know that.
Title: Re: Loosening blade tension when saw not in use
Post by: WV Sawmiller on May 11, 2022, 09:46:36 PM
   I'm sure glad I never tried to do anything like that. ::)
Title: Re: Loosening blade tension when saw not in use
Post by: kelLOGg on May 12, 2022, 07:27:17 AM
I could say that I have never done that either but there are those that would know I am lying. Once I was swapping out bands and explaining to curious onlookers about the sawing process, etc., and started the engine before tensioning - they got to watch it again. I told them I did that so they would know not to do it that way. ::)
Title: Re: Loosening blade tension when saw not in use
Post by: Magicman on May 12, 2022, 08:44:09 PM
Quote from: Magicman on May 11, 2022, 01:33:49 PM
I hang my leather apron on the tension knob at lunch time.  

(https://forestryforum.com/gallery/albums/userpics/20011/IMG_2237~0.JPG?easyrotate_cache=1652402370)

My "de-tensioned" blade tension knob/screw while I ate lunch today.  :)
Title: Re: Loosening blade tension when saw not in use
Post by: Stephen1 on May 12, 2022, 09:46:37 PM
I will drop the tension at night. At home I will leave the blade on, but travelling I take the blade off to come home. 
MM I always like to have a log loaded for when I come back from lunch also!
Title: Re: Loosening blade tension when saw not in use
Post by: Magicman on May 12, 2022, 10:08:06 PM
Yes, ready to go.  I seldom leave a log on the sawmill at night but I do like to have one at the loader and ready to go like I have right now.  ;D
Title: Re: Loosening blade tension when saw not in use
Post by: caveman on May 13, 2022, 05:42:47 AM
Quote from: Magicman on May 11, 2022, 01:33:49 PMI hang my leather apron on the tension knob at lunch time. 
I hang my ear muffs on the tensioner when it is loose.  I don't have a leather apron...yet.
Title: Re: Loosening blade tension when saw not in use
Post by: Mountain_d on May 15, 2022, 07:32:57 AM
I have noticed on my LT40 that the blade tension gauge will increase as the blade cools down so I loosen my tension if I shut down for 20 or 30 minutes. I think I read somewhere that higher pressure could cause a failure of seals for the hydralic tensioning mechanism. I guess that tensioner crank handle is a manual operated hydralic system. Mountain. 
Title: Re: Loosening blade tension when saw not in use
Post by: Magicman on May 15, 2022, 07:53:50 AM
That warning and recommendation is in the Wood-Mizer Operating Manual.  :P