Tensioning bandsaw without a gauge

[Aaron Craven]

I'm trying to figure out the best way to set the tension on a Porter Cable bandsaw that is apparently missing part of the built-in gauge. There are markings next to the spring (1/8", 1/4", etc), but nothing actually points to them... I've tried the "flutter" test, but it doesn't seem to work for me (or I'm just doing it wrong). Of course (if it isn't already obvious), I'm a bit of a novice at dealing with this machine.

Any tips?

Also, how critical is it that the bandsaw (as a whole) is perfectly level? At its current location, it's on an uneven wooden floor and it's very difficult to keep level.

[Erik Loza]

What specifically about the flutter test isn't working for you?

Regarding leveling, it's pretty important as far as I'm concerned. Not necessarily "leveling" as much as making sure that the base has solid contact with the floor. Bandsaws are one of the most vibration-prone machines in the shop.

Erik

[Prashun Patel]

You can use the finger test to get you in the ballpark.
Raise the guides as high as they'll go.
WITH THE SAW OFF (duh!!!!) push your finger against the side of the blade in between the guide and the table. You'll have to remove the throat plate.
Tighten until you get about 1/4" deflection.

Then you can try for your flutter test.

I can never get the flutter test right.

[Myk Rian]

I find the flutter method works best with a 1/2" blade. Anything else I just guesstimate it.

[Aaron Craven]

What specifically about the flutter test isn't working for you?

I'm not sure, to be honest. Adjusting until the flutter is gone leaves me with a blade that seems like it doesn't have enough tension (wandering cuts, deflection, and just doesn't "feel" right). I suppose I should mention I primarily use the saw for cutting bowl blanks, if that helps any. I also currently have trouble just getting the blade to track under tension, but I'm almost certain that's just a blade that needs replacement. I probably need to replace the tires too, though they seem to have a little life left in them.

I don't seem to have any major vibration issues, and I think the saw is making good contact with the floor, so I suppose that probably isn't contributing to my problems.

[Lee Schierer]

Here's some pretty good videos on how to do the flutter test. Flutter Test (https://www.youtube.com/watch?v=z8zZuDosSy0) Another Flutter test (https://www.youtube.com/watch?v=chyo9chuwJs)

[Jim Finn]

Search for the "Alex Snodgrass" video on band saws. He shows how to tension the saw and a lot of other info. on setting one up.

[Chris Padilla]

You can use the finger test to get you in the ballpark.
Raise the guides as high as they'll go.
WITH THE SAW OFF (duh!!!!) push your finger against the side of the blade in between the guide and the table. You'll have to remove the throat plate.
Tighten until you get about 1/4" deflection.

Then you can try for your flutter test.

I can never get the flutter test right.


This is what I do except I don't do the flutter test. I use my finger. That's it. :)

But I also have a MM20 band saw so it is a bit more stout than your PC one. :)

[Aaron Craven]

I appreciate everyone's comments. Also the video links. I watched all three, and they're very informative (especially the Alex Snodgrass one). I'll give all this a shot and hopefully get things working right again.

Thanks!

[Allan Speers]

I'm not sure, to be honest. Adjusting until the flutter is gone leaves me with a blade that seems like it doesn't have enough tension (wandering cuts, deflection, and just doesn't "feel" right). I suppose I should mention I primarily use the saw for cutting bowl blanks, if that helps any. I also currently have trouble just getting the blade to track under tension, but I'm almost certain that's just a blade that needs replacement. I probably need to replace the tires too, though they seem to have a little life left in them.

I don't seem to have any major vibration issues, and I think the saw is making good contact with the floor, so I suppose that probably isn't contributing to my problems.


Most likely you don't have everything else setup perfectly, (fence parallel with the blade, etc etc) or your blade is getting dull.

[Mark Mallia]

I appreciate everyone's comments. Also the video links. I watched all three, and they're very informative (especially the Alex Snodgrass one). I'll give all this a shot and hopefully get things working right again.

Thanks!

I use the finger test, but on the side away from the guides where there is a longer span. The amount of deflection depends on the width of the blade. I don't even know exactly the size of the deflection, just that you will learn to feel the tension after a while, halfway between "wobbly" and "damn blade keeps breaking".

[John K Jordan]

Aaron, unfortunately, even if the bandsaw gauge was there it probably can't be trusted. Years ago I bought a Starrett tension gauge and the built-in gauge of every bandsaw I tested was way off, every one way too low. On my 18" saw I have to tension to nearly the 1" blade width mark to get a 1/2" blade correct.

Do you know anyone who has a gauge you can borrow? The Starrett is kind of pricey but there are cheaper ones. Iturra design sells one for about $130 the last time I checked. I suspect they still don't have a web page, but I think their phone number is still 904-642-2802

If you can get a copy of their catalog it is great resource for setting up and maintaining a bandsaw.

JKJ

[John K Jordan]

Some useful reading on the subject, perhaps: http://www.finewoodworking.com/tool-guide/article/setting-bandsaw-blade-tension.aspx

Lonnie Bird is a well known author and woodworker. I keep his bandsaw book handy as well as the one by Mark Duginske.

JKJ