Bandsaw Problem

[tinytim1458]

Hi I have a friend with a bandsaw but it keeps breaking blades all the time and not at the joints as you would expect.
He had bought several blades from different suppliers and they still break after a small bit of use.
Could you advise if you can if you have had the same problem and how you sorted it out or if anyone had any ideas why this might happen and what can be done about it then I can let him know what to do.
Thanks Tim

 

[Beau]

Once had this and it was caused buy using too thick blades on a smallish bandsaw. They simply developed metal fatigue and snapped. Alternatively he might be over tensioning them.

 

[Alexam]

Hi Tim,
this does sound like over tensioning the blade. Which bandsaw do you have?

One of the most important factors in using a bandsaw is the tuning. See this -

THE BEST FROM A BANDSAW 'Alex Snodgrass of Carter Industries has an excellent video https://www.youtube.com/watch?v=wGbZqWac0jU on a tune up method that works well, but if you want to get the best use of your bandsaw on an ongoing basis, then the Steve Maskery DVD's will show you far more and they are a real investment. http://www.workshopessentials.com/shop/ '.

A Flutter test Video - https://www.youtube.com/watch?v=z8zZuDosSy0

The flutter test is in connection with getting the right tension if you do not have any tensioning guage, or the guage is incorrect.

Let us know how you get on.

Alex

 

[Phil Pascoe]

As above. I've not broken a blade in thirty years.

 

[NazNomad]

Great post, Alexam.

I'm a bandsaw newbie and have been reluctant to buy more blades (yes, I've snapped all the ones I had) until I knew a bit more about what I was supposed to be doing.

 

[marcros]

is it a small 3 wheeled bandsaw, or a 2 wheeled one? The small 3 wheeled ones can be a bit more sensitive with what blades they will run. I know that tuffsaws recommend that a certain material is used for these, whereas the 2 wheeled ones are happy on all of them, providing that they can tension them.

one point, however. I have a big axminster saw that will take a 1" blade- it actually will, rather than just claim to- that gives an idea of the rigidity of it, and spring size. I have used it with much narrower blades, and even getting them "nice and tight"- probably tighter than necessary when I was learning to use the machine, i do not feel that I have ever been in danger of snapping a blade.

 

[badabec]

I used to snap blades on my old 3 wheel saw because I used too thick a blade, as Beau points out.

On my new 2 wheel saw, I followed the youtube videos but still couldn't get rid of the flutter. Then I removed the tyres and put them in my ultrasonic cleaner. Now they are spotless and I have no flutter at a much lower tension.

I can't just crank up the tension like in the flutter video whilst the saw is running without having to alter the angle of the top wheel, maybe my saw is faulty (Elektra Beckum 315). I do it in stages, turning the top wheel by hand and adjusting until the bottom of the gullet is in the middle.

 

[woodpig]

Thanks for the Flutter test link Malcom, I've not seen that before!

Don't let Matthias Wandel see that Powermatic bandsaw though, he won't like the way the guides are orientated on it! :lol:

 

[Steve Maskery]

Yes, all above good.
Remember that on a BS with small wheels, like an entry-level benchtop model of an old 3-wheeler, the bending radius of the blade is much tighter than a large floor-standing model, so the blades are bent tighter, and, because they are short, the teeth come round more often, so each tooth does twice as much work than a blade twice its length. This all adds up to shorter blade life.

Using a thin-kerf blade that is more flexible should result in a longer life, as it is not as stressed by the bending.
S

 

[tinytim1458]

Thanks for the info guys.
I will not see my friend till after the Christmas holidays as I see him I'm my local mens shed in Nailsworth but when I see him I will give him your info which does sound very likely that is the solution to the problem.
thanks again guys.
Tim

 

[sploo]

Just my $0.02 - from evidence I've seen it's probably very difficult to over tension all but the smallest of blades. You're far more likely to damage the tensioning mechanism on your saw than snap the blade.

I'd suspect it'd be more likely that something was set up incorrectly (such that it's putting some strange loads on the blade - or rubbing), or, as already mentioned, a too thick blade being used on a bandsaw with small wheels.