Guitar tuner

[James E. Welch]

I've heard that proper tensioned blades make a certain note (although I don't know what note) but has anyone actually tried using a guitar tuner to see what it does? I happen to have a cheap tuner from an endeavor into learning to play the guitar that I failed miserably at. Lol  

I've been testing it on the hegner and from what I can tell it says E when it's tensioned right. Just wondering if anyone has tried this. 

I know some will ask why and some will say this is dumb but just like with the clock post I made, I like gadgets and find tinkering with stuff neat. I'd not recommend using a guitar tuner to set your blade tension every time I don't think. I'm just curious if a proper tensioned blade does make a consistent note. 

[kmmcrafts]

Why? that's just dumb..  Sorry I just had to since you said someone would and I wanted to be the first  

I remember someone posting about using one some years ago and you guessed right.. many asked why and that's stupid or overkill etc etc.. Anyway, I think I've read many different times that a proper tensioned blade should be about a "C" note... whatever that is supposed to be.. Like you, I don't have the music talent or the ears for that either. My older brothers stole all of that from the younger of the siblings as two of my brothers play in bands and actually have some music published through a recording company.. Guess they are good at it.. I wouldn't know since they've stole all the ear talents from us younger siblings 

NOW, with that said.. couldn't one play some music from a scroll saw.. you have the ( what's it called? Reverb bar? ) tension lever to change the tune of a single string ( blade in this case ).. I would say someone would have a lot of talent if they could play a song using a scroll saw and blade tension lever only. LOL I might suggest this to my talented brothers, 

[Sycamore67]

You can get a frequency app for most phones that would do that.  Given the different size, thickness and teeth of different blades, the frequency would vary blade to blade.  

Personally, I do not pay very much attention to the exact tension.  Close is good enough.

[Scrappile]

I would be more curious if the right tension had different notes for different blades and different scroll saws. So many variables.  I do pluck my blade every time I clamp one and before I turn the saw on, but I think I go more by the feel than the sound.

[kmmcrafts]

4 hours ago, Sycamore67 said:

You can get a frequency app for most phones that would do that.  Given the different size, thickness and teeth of different blades, the frequency would vary blade to blade.  

Personally, I do not pay very much attention to the exact tension.  Close is good enough.

Never gave it much thought about the frequency changing with different sized blades.. I've always just read that it should give a hi C note.. But that note couldn't possibly be made with a big ol hacksaw type blade.. I've never used anything larger than a #7 and that's really rare for me to use that big of one.. also don't use much smaller than a #1 either. 

Anyway, this means whoever says it should have a C note.. is only partly right  

[OCtoolguy]

35 minutes ago, kmmcrafts said:

Never gave it much thought about the frequency changing with different sized blades.. I've always just read that it should give a hi C note.. But that note couldn't possibly be made with a big ol hacksaw type blade.. I've never used anything larger than a #7 and that's really rare for me to use that big of one.. also don't use much smaller than a #1 either. 

Anyway, this means whoever says it should have a C note.. is only partly right  

Maybe they were referring to a $100 blll.

[Sycamore67]

While I would not use any frequency app, I can understand a new scroller trying something.  For them, learning to properly tension a blade can be somewhat difficult.

Out of curiosity, I may just measure the frequency on my Hegner.

[BadBob]

Yes, you can use a guitar tuner. You need one that has a microphone in it. Place it next to the blade and pluck away. I used a tuner for setting the tension on some of my previous saws.

[Gene Howe]

I've no ear for musical notes but, I can recognize the ping of a properly tensioned blade. Well, properly tensioned, for my needs, anyway. 

[barb.j.enders]

Well now!   I may just have to grab one of hubby's guitar tuners and take the challenge of creating a song!!!  

 

 

NOT!  

[Sycamore67]

Well,I had an interesting morning.  I installed a frequency analyzed in my Samsung phone and used it to determine the frequency of how I tension blades.  I put in a FD Polar#5 in my Hegner and tensioner it to my normal.

I was not real happy with what I got so I found website that will play different keys on the piano.  My blades are definitely not at middle C but more in the E or F range above middle C.

Will I ever do this again no as it really does not help me.

 

[BadBob]

36 minutes ago, Sycamore67 said:

Will I ever do this again no as it really does not help me.

I did it because I kept breaking the #1&#2 blades.

[Sycamore67]

I do not use small blades so can see there may be a difference.  I bet the smaller blades have higher pitch.

[BadBob]

1 hour ago, Sycamore67 said:

I bet the smaller blades have higher pitch.

Smaller blades are set to the same pitch as the larger ones. Larger blades need more tension to get there. Smaller blades need less tension. My problem when I first used the tuner was that the tension adjustment was so coarse that it was easy to snap a small blade. I used the tuner to determine what a correctly tensioned #5 blade was set for and then backed the tension off, mounted a small blade, and used the tuner's meter to sneak up on the tension. It worked, and the blade did not break. The tension was between C & C#. Out of curiosity, I checked the blades mounted in my Pegas and EX21 saws today. The Pegas with a #2 blade was C#, and the EX21 with a #3 blade was a C#. The arms are set parallel with the table and I never adjust the tension.

I used a Korg TM-40 tuner with a meter so I could see what I was doing. Some tuners only have LEDs and might not work for this.

 

 

Edited July 21, 2023 by BadBob
Correction.

[rash_powder]

If it hasn't already been mentioned, different blade thicknesses will produce different tones at the same tension.  

So, let's do math!

(blade stretch/distance) x young's modulus = tension in psi

x/5" x 29000000 = 15000psi          young's modulus for steel is 29000000, bandsaw blades are good for 15000psi, so a

                                                           good stand in for us

x = .0026" of stretch over 5" of blade or .00052" per inch of blade

psi x area = tension in pounds

15000 x (.032" x .014") = .000448lbs or .007168oz      .032 x .014 is an Olson crown tooth #3

More importantly, 1500psi is consistent from blade to blade, so stretch can be found easily.  We also can work out how much stretch we give the blade via the thread pitch of the adjusting screw and the lever arm.  So things could be dialed in exact.  

Or, as Hegner recommends, somewhere between 1/2 and 1 turn after the slack is out.  Then account for user preference and people who do not have 'perfect pitch'.  

Basically, don't go farm tight; just a light finger tight.

[OCtoolguy]

5 hours ago, rash_powder said:

If it hasn't already been mentioned, different blade thicknesses will produce different tones at the same tension.  

So, let's do math!

(blade stretch/distance) x young's modulus = tension in psi

x/5" x 29000000 = 15000psi          young's modulus for steel is 29000000, bandsaw blades are good for 15000psi, so a

                                                           good stand in for us

x = .0026" of stretch over 5" of blade or .00052" per inch of blade

psi x area = tension in pounds

15000 x (.032" x .014") = .000448lbs or .007168oz      .032 x .014 is an Olson crown tooth #3

More importantly, 1500psi is consistent from blade to blade, so stretch can be found easily.  We also can work out how much stretch we give the blade via the thread pitch of the adjusting screw and the lever arm.  So things could be dialed in exact.  

Or, as Hegner recommends, somewhere between 1/2 and 1 turn after the slack is out.  Then account for user preference and people who do not have 'perfect pitch'.  

Basically, don't go farm tight; just a light finger tight.

You lost me in the second sentence.

[Sycamore67]

I thought the math and assumptions were a good analysis.  

I have used similar analysis to help calculate tension on my band saw.  You can measure the stretch on a bandsaw blade and then calculate using the same formula the tension.

[James E. Welch]

13 hours ago, Sycamore67 said:

Well,I had an interesting morning.  I installed a frequency analyzed in my Samsung phone and used it to determine the frequency of how I tension blades.  I put in a FD Polar#5 in my Hegner and tensioner it to my normal.

I was not real happy with what I got so I found website that will play different keys on the piano.  My blades are definitely not at middle C but more in the E or F range above middle C.

Will I ever do this again no as it really does not help me.

 

I've found I'm in an e range too. 

[James E. Welch]

I just want to say that you guys never disappoint when it comes to a good discussion. I'm glad I brought this up. 

[rash_powder]

This really has me super curious now.  It’s something I’ve wondered for quite some time too.

 

I’m 3 hours from home this weekend, but when I get back I may measure the thread pitch of my tension rod and the lengths of the levers involved and see what I can figure out.  

[James E. Welch]

1 hour ago, rash_powder said:

This really has me super curious now.  It’s something I’ve wondered for quite some time too.

 

I’m 3 hours from home this weekend, but when I get back I may measure the thread pitch of my tension rod and the lengths of the levers involved and see what I can figure out.  

I'm glad I'm inspiring curiosity. Lol  

[crupiea]

I have heard this too and tried it but didnt get better results than just cutting a quick line and seeing how well it goes. Too squigly and hard to control, add a bit more tension.  

[BadBob]

If you are a beginner and don't know what the blade ping sounds like, this could be helpful.

[rash_powder]

So somewhere I did bad math.  
 

to get the 15,000psi a bandsaw would like, we have the equivalent of 6.72lbs on the blade, and a stretch of .002586” over the 5” blade.

 

my hegner 22” saw has a tension rod with 1 thread per mm; one rotation changes its length by 1mm.  The back portion of the arm is 19cm and the front is 40.3cm.  That gives a mechanical advantage of 2.12; so 1mm of shortening the tension rod is 2.12mm of stretch on the blade.

 

2.12mm is .0835”.  This is the max Hegner recommends.

 

1 turn of the adjuster yields 484,300psi for a pull of 216.917lbs

 

1/2 turn yields 241,860psi for a pull of 108.35lbs

 

all based on an Olson #3 crown tooth.  
 

those little blades are really under a lot of load!  It’s no wonder the blades break.

 

so that’s it.  Curiosity is satisfied 

 

 

[kywoodmaster]

WOW You guys have way too much time on your hands!!!!  Just make sawdust.