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Highpower
10-28-2009, 12:53 PM
Today I finally ordered myself a horizontal band saw since I've grown very tired of exercising my arm with a hack saw. :rolleyes:
(Enco 7x12, with the optional UL listed motor.)

I was skimming through the on-line owners manual and I came across this:


6. TO PROLONG BLADE LIFE ALWAYS
release blade tension at the end of each work day.Since I've never owned a band saw before :o I have to ask - is this commonly practiced among you that own them?

Jim Caudill
10-28-2009, 01:13 PM
Personally, I never have done that. However, I haven't had any of those generic small saws either. Someplace, there is a whole forum devoted to nothing but those small saws. I would do a search for it. Those saws are like a swiss army knife: you would not believe all the modifications and tips that are available for owning/using one. The biggest recommendation That seems universal is don't even think of using the stock blade - it's a total waste of time. Order a quality Starret, Lenox, or some other blade immediately. Once you get the new blade installed, you can proceed to make the alignment adjustments, break-in the new blade, and tweak the saw to give satisfactory service. I have an old Wells saw that I had difficulty with because I was using industrial blades made by a shop here in Dayton. Once I bought a "pre-made" Starret blade, all my troubles went away.

Carld
10-28-2009, 01:26 PM
I don't know who can up with that idea. There was no shop I worked in that did that and I don't know how it could help prolong blade life. For one thing, you forget to tighten it up and BINGO your now putting the blade back on the wheels and tightening it up.

Do you loosen your hacksaw blades between use? I don't and I don't loosen the band saw blades. Oh BTW, buy and use bi-metal blades.

Highpower
10-28-2009, 01:44 PM
Oh BTW, buy and use bi-metal blades.I intend to do just that, but I'm going to wait and see what condition the saw arrives in first.... :rolleyes:

I've seen a couple horror stories on the net, and saw a couple more in my local Horror Freight stores. :eek:

Rich Carlstedt
10-28-2009, 02:12 PM
The issue of releasing the blade tension is not a good idea.
The only time it would be of value is if you were moving the machine over a sizable distance, but certainly not within a shop.
You could say that a mis-alligned blade could take a "set" but to do that, you would need severe temperature changes to take place to cycle the metal molecules. . You will hav far more damage caused by errors in wheel and guide allignment.
Rich

J.Ramsey
10-28-2009, 02:18 PM
The Enco 7x12 is made in Taiwan and is an excellent saw for the money.
Mine has cheaper motor and has been used daily for the last 6+ years with no problems.


IIRC back then I paid $625.00 shipped to my door.


Toss the supplied blade after about a dozen cuts.

airsmith282
10-28-2009, 02:33 PM
bans saw blades are liike guitar srings if oyu pratice that you will cause premature ware in parts and other damages down the road happen that can be avoided if you just tighten it up and leave it alone the entire saw last longer , the only time i losen my band saw blade is when i intend to change it , i a regular band saw thats also made for cutting metal as well so i have a metal blade set and a wood set of blade this way i jst use when i need when i need to and these days its 99% metal use only

a saw blade will strech with use which is way you need to make it tighter from time to time, evetually the blade will ware out and so then you just repalce it,

allwing hte blade to release its tension when not in use then tighten again when it it what happens is whats called the rubber band effect and then you ask your slf how did it snap so easy , guitar strings work the same so you need to keep the tension on them for 2 reasons ! logner life of the strings and B longer neck life , you know what a banana looks like that what happens to the neck of a guitar if you always detun it all the time when not in use the truss rod also gets damaged beyond repair, so same goes in hte band saw adjuster s and other parts will damage sooner then they shoud and not only wil hte blade snap but you can also send other crap flying and thats not safe either..

wierdscience
10-28-2009, 02:37 PM
Today I finally ordered myself a horizontal band saw since I've grown very tired of exercising my arm with a hack saw. :rolleyes:
(Enco 7x12, with the optional UL listed motor.)

I was skimming through the on-line owners manual and I came across this:
Since I've never owned a band saw before :o I have to ask - is this commonly practiced among you that own them?

I had a bandsaw mill that had to be released every day.but it had a solid tensioner on it.The better saws feature a spring under the tension screw so that in reality you are really loading a spring.In this case it shouldn't matter one bit since the spring is there to compensate for blade expansion and contraction.

If it doesn't feature a spring tensioner I would release the tension.Those blades grow a bit when the warm up during operation,when they contract they tend to put a lot of force on the saws wheels/bearings etc.

A spring tensioner can be added easily also.

Bill Pace
10-28-2009, 02:39 PM
It is indeed hard to imagine where "loosen the blade when not in use" came into it:confused:.

As already mentioned I too have never practiced it, and have never met anyone who has. As far as the smaller saws are concerned, I had a little 4x6 for 20 plus years and the same blade sometimes would last for 3-5 years when I wasnt able to frequent the shop for some reason or other, and never be loosened. In fact the first blade I had ever to break happened only about a year ago - then I had a rash of breaks, investigating it I determined it was a batch of 4 that I had got and apparently was defective.

housedad
10-28-2009, 02:49 PM
I always thought that it was due to not putting a permanent imprint in the tire around the wheel, and to keep the blade frome getting a round "set" from the wheel. The set would not happen overnight, but has happened on my wood bandsaw from sitting for a couple of weeks.

airsmith282
10-28-2009, 02:59 PM
I always thought that it was due to not putting a permanent imprint in the tire around the wheel, and to keep the blade frome getting a round "set" from the wheel. The set would not happen overnight, but has happened on my wood bandsaw from sitting for a couple of weeks.


on wood blades you have to watch you dont use to much tension on them and thats what likey had happen to you , i never had a problem yet, and i use any where from 1/8 to 1/2 inch blades in my saw even my tires are sill just like new, and yup i have a tensioner spring and it does it job as it should, when i use the metal blades i do tension them up a bit tighter then i would on the wood blades onyl cause i found that using less on the metal blades caused a few jumps that scred the hell out of me so now they get more tension on them then the wood blades do..

gnm109
10-28-2009, 03:01 PM
I have an Enco 7X 12 H/V bandsaw that was built in 1987. I bought it from the original owner in 1994 and other than when the blade is changed it's always been under tension. I can't think of any benefit to running the tension down.

In fact, whenever I release the tension on the saw in order to change blades, it takes me five to ten minutes to get the blade running straight again. That's a strange idea. I've never heard of that before.

Carld
10-28-2009, 04:28 PM
I know of saws that have been used for over 50 years and have never had the tension released and they are doing just fine today.

camdigger
10-28-2009, 07:35 PM
I don't see the benefit of relieving the blade tension on a metal cutting bandsaw either, because the wheels don't have the same rubber tires as wood cutting bandsaws.... Is it possible that statment in the owners manual is a "legacy" bit of boiler plate in a manual written by a supplier that builds both wood and metal cutting saws???

TECHSHOP
10-28-2009, 07:43 PM
On my wood band saws, I will back off the tension if I am not going to use it for a few days. I may even take the blade off if I expect not to be using it for "a while" (that keeps me from being to lazy by not changing to the "correct blade" before I used it again). On the metal cutting bandsaws, I only mess with the tension when something goes wrong and I need to make an "adjustment". There is usually a difference in the "design" between the two "types" of bandsaw as to "frame stress in use", bearings, and such.

gnm109
10-28-2009, 07:50 PM
I don't see the benefit of relieving the blade tension on a metal cutting bandsaw either, because the wheels don't have the same rubber tires as wood cutting bandsaws.... Is it possible that statment in the owners manual is a "legacy" bit of boiler plate in a manual written by a supplier that builds both wood and metal cutting saws???


That could well be. I also have a 14" Delta-Rockwell wood-cutting vertical bandsaw that I purchased new in 1971. It always has tension on it and it's only needed one replacement set of rubber tires in all of that time. It's been used quite a lot, too.

I didn't get the manual with my 1987 7X12 Enco machine since the former owner had misplaced it. A few years ago, I called Enco and they mailed me one for a 1998 model that is very smiilar. I just looked at the manual this afernoon and the suggestion to run the tension down is not in the manual.

That's good enough for me.

Mike Burdick
10-28-2009, 09:05 PM
For what it's worth this is what a very good cabinet maker told me many years ago... I suppose old time machinist using metal cutting band saws have the same reason.

This craftsman worked in a shop and since he did not know for sure if the "last" guy to use the saw set the blade to its proper tension it was shop policy to always back off the tension when finished. He said to set the tension they used the "flutter" method. First he would set the saw for the desired depth of cut and then back off the tension until one would see the band just start to flutter. Then he would start adding quarter turns of tension, slowly, until the band stopped fluttering and was running stable again. At this point he added one more complete turn of tension. If the band is not set to its proper tension the blade will wander and not produce a square cut.

.

Paul R
10-28-2009, 09:12 PM
I think the concept of detensioning a band saw blade came from the concern that the rubber tires would get deformed if they were left compressed for long periods of time. If that happens, then the balde would not run smoothly. Modern rubber tires (they are really plastic in most cases I suspect) do not seem to deform in my experience at the tension levels used for most smaller bandsaws, so I would say that detensioning is probably not required. In fact, frequent tensioning and detensioning of the machine would seem to introduce more wear on the spring/bearings/etc. than just leaving it alone.

Bill736
10-28-2009, 09:17 PM
I think housedad is correct; continual tension on the bandsaw blade will cause the rubber tires to deform . In fact, everything on a bandsaw, from bearings to frame to the upper spindle support will be more likely to wear or bend if tension is kept on the blade. Having said that, I never do release the tension on my bandsaw blades, since it takes too much trial and error to get the tension set right in the first place. (Only one of my bandsaws has a built-in tension gauge.) About guitars ....my local guitar player tells me that if tension is left in guitar strings, the guitar neck will almost certainly warp, which is apparently bad.

J.Ramsey
10-28-2009, 09:26 PM
I think housedad is correct; continual tension on the bandsaw blade will cause the rubber tires to deform ..


The 7x12 Enco saw in question has cast iron wheels.

motorcyclemac
10-28-2009, 09:26 PM
I have a 7x12 Grizzly and I never release the tension. I have had zero issues related to blade tension. I will tell you that it makes a big difference to toss the crappy blade it comes with and buy a Lennox bi-metal for steel and a good quality blade for aluminum only. I do swap blades to cut aluminum as I have an agressive tooth aluminum blade. It makes a difference. I would also recommend that you seek and buy a gallon of Lennox brand "band aid" cutting fluid. I use it and really like the way it performs. Good stuff.

Cheers
Mac.

spope14
10-28-2009, 09:27 PM
Oh, geeze, the bandsaws I have are at the 30 year old range and now I hear this about releasing tension? No wonder my blades only last about a year or two with hard use.

jeepnxj96
10-28-2009, 09:31 PM
I have a 9x12 horizontal at my home garage (not sure on brand) and a Do-all 9x16 and a Marvel vertical at work, never ever release the tension on any of them, never a single problem. We always use Amada blades though, and those would be my preferred blade choice:D

Bill736
10-28-2009, 10:00 PM
The 7x12 Enco saw in question has cast iron wheels.

Some metal cutting bandsaws have rubber tires, some do not. The thread had obviously been expanded to include bandsaws other than that Enco model.

steve45
10-28-2009, 11:28 PM
The first bandsaw I had was a tabletop model that was made of a composite material. (Mongtomery Ward brand, IIRC). Releasing the tension was recommended in the owner's manual, and it had a quick release lever to do so. In this case, with the composite frame, it probably kept the frame from deforming over time.

On my current wood and metal bandsaws, I never release the tension.

hitnmiss
10-29-2009, 09:39 AM
I release the tension in my Harbor Freight 4x6 about every time I use it (unintentionally when it pops off!)

That saw is 10000% better than a hack saw but I can't wait till I get a bigger shop and have room for a "real" band saw...

Highpower
10-29-2009, 10:03 AM
Well, it didn't make any sense to me to have to relieve the blade tension every day - but again, since will be my first machine (band saw) I had to ask.... :o

Maybe it is just a carry-over from another manual -- maybe it was something lost (or gained) in translation of the Chicom manual -- or maybe it is just an indication of the faith they have in their "junk" factory carbon steel blades.... :rolleyes:

At any rate, I went ahead and ordered a few Irwin bi-metal blades to use for good stock, and will save the factory blade for cutting up unwanted scrap material for disposal. I'm sure a spirited discussion on the type and brand of blades to use would make for a rather lengthy thread of it's own, but I'll leave that for another time. :D

Thanks for everyone's input!