On 3/4/2019 11:00 AM, pyotr filipivich wrote:
on Mon, 4 Mar 2019 07:30:34 -0800 (PST) typed
in rec.woodworking the following:
On Wednesday, January 14, 2004 at 9:41:33 AM UTC-5, DJ Delorie wrote:
Greg G. writes:
Every time you bend the blade around a wheel, it results in fatigue.
Eventually, the constant bending and straightening of the blade
results in breakage.

If the wheels are the same size and distance apart, and the motor RPM
the same, the blade is subject to the exact same bend/straight
cycling, so there should be no more fatigue than with only two wheels.
In fact, there may be less because the blade is bent for a shorter
time each time it bends (120 degrees around instead of 180).

You are right both 2 and 3 wheel blades go through the the same 360 degrees of bending during each revolution and the degree of bend for each wheel is less on a 3 wheel unit. However There are still 3 bend/straight cycles on a 3 wheel and only 2 on a 2 wheel.

And on a 3 wheel bandsaw, there's one more set of wheel, axle,
bearings, etc to add to the machine.

But you get more throat clearance for the given length of blade...and in
some 50 years, I've yet to have a BS blade fail by "fatigue"...

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