BS blade tension ? - TriMaster on MM16

[Doug Shepard]

I didn't want to derail Joe Pelonio's band saw tension thread with this, but what do you MM16 owners using the Tri-Master blade set your tension to? I'm not looking for a number value, just a ballpark reference. According to MM's manual their "flutter test" should have me setting the tension so that the blade deflects around 3/8" with moderate finger pressure against the blade. That seems real loose to me with what I'm used to on my old Jet BS with a Woodslicer blade. When I tension it to something that feels right, I'm about 1/4" - 3/8" past the line on the built in tension gauge for blades that wide. I don't expect the tension gauge to provide a quantitive tension measurement, but am I putting on too much tension? Do the rest of you tension past the mark or run them looser?

[John Brennaman]

Doug,

I have been wondering the same thing. When I use the flutter test it seems too loose to me. I have to tighten the blade a little further than what the gauge says for it to feel good and not float. I will probably keep doing it that way for a while and then take the tension off when I am through using the saw.

Anybody else have any ideas?

[Cecil Arnold]

Doug, this is another can of worms you've opened . Depending on what authority you are listening to and what blade you're using you will get a different answer. Louis Ittura, who seems to be the acknowledged band saw guru, says that a blade needs to be between 20-30,000 psi. Timberwolf started the flutter setting thing and many people swear by it, while Ittura doesn't seem to agree. I am using a carbon 1" on my MM16 and using a tension gage find that I'm taking the pointer to a very high level and with the guard all the way up (mine is 12 3/4" re-saw) I may be able to get 1/4" deflection. That's set at 25,000 psi and it gives me good cuts with very little drift. If you don't have Louis' catalog you should call for one. There is more information on BS than you get in most books, and it's free. You can do a search of the threads for his number.

[Chris Lee]

I agree with Cecil. I always thought the flutter method was only for Timberwolf's special silicone steel or whatever it is. I was under the impression that bandsaw blades need the tension. I know when I don't put enough tension I find it hard to track as good, especially when resawing.

Chris

[Doug Shepard]

Cool. Sounds like I'm already about where I need to be just going by my highly technical "gut feel" approach. I just thought I'd ask, so that a couple years from now if/when it came up that you all didn't say "You put HOW much tension on it? Geez - no wonder your saw broke."
Cecil - you're right about Iturra's catalog being a good resource. I've got their first catalog, but think I need to ask for one of their newer ones. I dont think the flutter topic info you mentioned is in mine.

Muchos gracias.

[tod evans]

for over 25 years i`ve "plunked" the tensioned blade like a guitar string but not being a musician i can`t tell you what note to listen for but on the minimax scale for my small saw the 16, i keep a 1/4" blade on it and the tension gauge reads for a band of 3/4 or so. on my larger saw i keep a 1/2" blade and "plunking" reads for 1-1/8 if i use a resaw blade on the large saw it`s at the upper end of the marks on the scale. .02 tod

[Gary Herrmann]

I've been dialing the pressure up till it reads between 22k and 25k on my tension gauge for my 1" Trimaster. Still dialing it in, but that range is giving me good results.

[Sam Blasco]

Cool. Sounds like I'm already about where I need to be just going by my highly technical "gut feel" approach...
Muchos gracias.

That's pretty much my approach, too. My gut and cut will tell me all I need to know. Though your gauge doesn't give you exact psi readings it is very repeatable. When you find a tension you like for a particular blade, mark it with a pencil, and you can come back to that tension every time. I was curious about all the gauges and different psi recommendations (I feel 20 - 30,000 psi is quite a wide range). A visiting friend, on my request, brought his tension gauge (1 of the three most mentioned). I followed the instructions carefully and did it three times taking the tension to my trusty mark and it seems I run my blade tension (1" Lenox TriMaster Carbide) between 17 - 21,000 psi (I got three different readings). Then he did it to the same mark three times and the readings were from 20 - 25,000 psi. I then had one of our technicians give it a shot and he came up with 15 - 20,000 psi on three different tries. All tests to the same mark, following the same instructions. Keep in mind some human error (eyeballing to a mark - different men reading the same instructions). Bottom line, I still don't know what is a "proper" psi for that blade, but I do know when it is cutting nicely and where to tension to to make that happen.
On my saw, same as yours only older, Doug, it is about 3/8" above the top mark for the 1" carbide. Sounds like you are on the right track.

[John sexton]

The proper tension for a Lenox 1" tri-master should be just about 26,000.
This I learned for a Lenox executive That used be in the sawmill business.
The 30,000 figure is for Lenox blades used for metal cutting.
I have a Lenox 1" carbide tri-master on a Grizzly 566 . The cut is OK but not as good as I was getting with a Timberwolf 1" carbide on a Grizzly 507.
The Timberwolf 1" carbide should be around 24,000.
The 566 is replacing the 507.It will be used only for resawing and has a power feeder on it.
I will be getting a 1" Timberwolf carbide for the G 566 and see how it does on this saw.
I am probably one of the very few people that have two new 1" carbide blades to test on a new saw and compare cuts.(Apples to Apples)
The results should be interesting.

[lou sansone]

As I posted in the previous thread I have found that at least for the timberwolf blades that the flutter test really works. I had tried this on my saw mill but with mixed results. In the end for the band mill it really did not make all that much difference because of what you are sawing ... big logs..

But for a ww band saw I did see a difference in the cut, feel and sound of the saw. I think that most of you folks have saws in the 16 to 18" range and for saws in that size range the flutter test might be harder to see in practice. It turns out that for larger saws and saws with very large "straightaways " or very large resaw capacity ( say in the range of 24" ) the flutter test is so bone simple that it is amazing. My 36" band saw makes this test very easy to do.

The way I have found to do this test is to tension the blade to some decent level that you sort of know would be reasonable to have the blade at. Turn the saw on and take a look at the blade in the straightaway area ( you will have to raise up the upper guide as high as it will go or in the case of some saws remove the opposite side guard so you can view the blade in the straight section... my moak has a very easy guard to remove, but still not pose any real danger to the operator ).

Ok now the saw is running and the blade is spinning around and you are looking at it. It may already be "fluttering", like someone has plucked it. If it is fluttering it will continue to flutter indefinitly. If it is not fluttering it will look as if it is "standing still". It does not matter either way for what you are going to do next. Keep your eye on the blade and slowly ( 1/2 turn per minute ) decrease the tension. Keep reducing the tension until you are sure that the blade is just way to loose or if you see the fluttering either stop or start. If you had the case that the blade was just rock solid when you first started and you reduced the tension and the blade started to flutter, you can inch back up on the tension and prove to yourself that the blade is really at the right tension. If you had the case the when you first started the saw up and the blade was fluttering and even though you reduced the tension it never stoped, what you need to do it go past your original tension setting and continue to tension the blade until it stops fluttering.

As with any mechanical system there are standing wave resonances. You might find that if you were to initially tension the blade and turn the saw on that as you decreased the tension the blade started to flutter. If you continued to decrease the tension you might find the blade stoped fluttering again. What that is telling you is that there are a few "nulls" where the mechanical resonances are at a minimum. Basically you can actually run the blade at a couple of different optimal non-fluttering tensions. I usually choose the lowest tension that causes the blade to settle down and still provides a decent cut.

I think if you give this a try you will be impressed at how simple it is and how quick it is to do.

lou

[Brad Olson]

The proper tension for a Lenox 1" tri-master should be just about 26,000.
This I learned for a Lenox executive That used be in the sawmill business.
The 30,000 figure is for Lenox blades used for metal cutting.
I have a Lenox 1" carbide tri-master on a Grizzly 566 . The cut is OK but not as good as I was getting with a Timberwolf 1" carbide on a Grizzly 507.
The Timberwolf 1" carbide should be around 24,000.
The 566 is replacing the 507.It will be used only for resawing and has a power feeder on it.
I will be getting a 1" Timberwolf carbide for the G 566 and see how it does on this saw.
I am probably one of the very few people that have two new 1" carbide blades to test on a new saw and compare cuts.(Apples to Apples)
The results should be interesting.

Not to go too far off topic, but it seems you like the timberwolf carbide better than the lennox trimaster? I priced it out and the TW carbide is about $40 more expensive than lennox so I just passed on it for the time being ($160 for trimaster vs $200 for TW carbide). Have you used the TW carbide enough to see how band wears over time? Just curious because there is a big unknown with TW and I know for sure with lenox I will get years of service with my needs.

[John sexton]

I run about 15,000 lineal ft of 6" and 8" cedar and some red oak through the Timberwolf blade and the cut was the same as it was new.
The cut I was getting on the Timberwolf blade was like the wood was sanded to 80 grit.I couldn't believe it myself and just about everyone that saw the cut thought it was phenomenal.
This cut was on a Grizzly 507.
I have a new 566 that I will be comparing the cuts of both new blades on. The 566 takes a 165" blade and the 507 toke a 162" blade. I can make the 162" blade fit but I would like to compare cuts with everything equal with both new blades on a new saw.
I don't have any bones to pick with Lenox they have been around a long time and make very good blades.
I resaw a lot of wood and I want the best cut and blade life I can get.
I understand that the teeth set on the Timberwolf is different then the Tri-master and I am looking forward to see how the blades compare.

[Ken Garlock]

We have to remember that the tension gauge is telling you how much the blade has stretched IF IT WERE A BLOCK OF STEEL ONE INCH SQUARE, NOT THE MOUNT OF ACTUAL TENSION THAT IS ON THE BLADE YOU ARE MEASURING. The actual tension on a blade is more like about 300 to 600 psi.

You may get a reading of 25,000 psi on a 1/4" blade with only an absolute physical tension of 300 psi. You may get a reading of 25,000 psi on a 1" blade with 600 psi actual tension.(just guesses) You are measuring the stretch on the blade and the gauge is converting it to a common measure, pounds per square inch.

Stop and think for a moment. Pull a string just tight, and pluck it; you will get a low pitch tone and the string will vibrate up and down a noticeable amount. As you increase the tension on the string, the pitch increases, and the amplitude of the vibration decreases. You don't want your blade to vibrate like a low C note because it can't be controlled when cutting. You want a blade that is a string that barely moves, it has less opportunity to wander as you cut.

Does this eliminate blade drift, not at all. But once you establish a consistent tension on your blade, you can adjust your fence for the drift and you are off and running. Put a mark on that grossly inacurate gauge on the saw so you can quickly get back to the correct tension for a specific blade.

[Alan Turner]

John,
I did not know that TW made a carbide blade. Shame on me. I have been running a 1" Lennox Trimaster on my Aggi for a few years, and like it a lot. The cut is great, but not like 80 grit abrasive. I just ordered a Lennox 1" from Iturra for my new-to-me Zimmermann 800 mm., and got a 2-3 tpi (25" resaw capacity). What is the set defference between the Lennox and the TW? More or less? Sometimes I am slicing exotics to veneer, and waste not, want not, so less sawdust can equal another slice or two from 8/4 stock. And, please keep us posted on the results of your tests between the two blades. Thx.

[lou sansone]

We have to remember that the tension gauge is telling you how much the blade has stretched IF IT WERE A BLOCK OF STEEL ONE INCH SQUARE, NOT THE MOUNT OF ACTUAL TENSION THAT IS ON THE BLADE YOU ARE MEASURING. The actual tension on a blade is more like about 300 to 600 psi.

You may get a reading of 25,000 psi on a 1/4" blade with only an absolute physical tension of 300 psi. You may get a reading of 25,000 psi on a 1" blade with 600 psi actual tension.(just guesses) You are measuring the stretch on the blade and the gauge is converting it to a common measure, pounds per square inch.

Stop and think for a moment. Pull a string just tight, and pluck it; you will get a low pitch tone and the string will vibrate up and down a noticeable amount. As you increase the tension on the string, the pitch increases, and the amplitude of the vibration decreases. You don't want your blade to vibrate like a low C note because it can't be controlled when cutting. You want a blade that is a string that barely moves, it has less opportunity to wander as you cut.

Does this eliminate blade drift, not at all. But once you establish a consistent tension on your blade, you can adjust your fence for the drift and you are off and running. Put a mark on that grossly inacurate gauge on the saw so you can quickly get back to the correct tension for a specific blade.

hi ken
I believe that you may be wrong on this issue. maybe you meant to state it differently, but the way it reads is not correct. When someone states that the blade needs 25000 pounds per square inch the actual tension on the blade will be 25000 X the area of the blade cross section. The units of square inches will cancel out and you will be left with pounds force. The spring on the BS will need to be able to exert twice that amount due the the fact that you have a "pully" arrangment with the blade. It just so happens that for common blades in the 1/2 width that forces in the 300 to 600 pound range are somewhat common.

lou