Robatoy wrote:
On Aug 20, 11:58 am, RicodJour wrote:
On Aug 20, 11:22 am, dpb wrote:





RicodJour wrote:
On Aug 20, 9:33 am, Robatoy wrote:
On Aug 19, 10:25 pm, RicodJour wrote:
You're doing a partial body diagram, and being mighty partial about
it. Yes, the heavier blade has a greater rotational inertial force,
but a heavier-as-in-wider blade also is cutting more wood, so it has
more drag. There's no simple answer.
No there isn't a simple answer, but everything else being equal, the
increased mass of a blade assists in the cutting action, like a bigger
hammer. Surely nobody is interested in too much geek detail, hence the
Readers Digest version of my statement. Not only is a more massive
rotational force advantage provable on a physical level, it is well
supported by personal observation and what industrial cutter heads
show to be most effective in their respective environments.
A set of solid 'stiffeners' on a table saw not only 'stiffens' the
blade, the added mass contributes to a better cut as well.
Apples and oranges, mon ferret. The stiffeners add rotational mass,
but no additional cutting resistance is added. Not the case with a
wider blade.
For sawblades kinds of masses, the inertial effects would be minimal at
best and the blade stiffener mass is concentrated near the shaft,
anyway. Besides, the inertia contained in the motor rotor, etc., is
multiples of that of the blade owing to the mass differences. Hence,
even though the blade mass may be sizable fractional difference between
the two, the system mass is essentially constant; ergo, so is the total
inertia.
I have to concur w/ the dominant issue (for equivalent sharpness, tooth
geometry, etc.) being that of amount of material cut per tooth far
overriding any of the other effects.
Right. Except for the stiffeners and blade, the whole system is a
constant, and as you say, the bite size is the predominant,
essentially only, variable.

R

The rotational mass of the motor is decoupled from the rotational mass
of the blade due to the elasticity of the belt. The extra mass
(regardless of how small it may be as we are not discussing HOW much
extra mass) will help smooth out the vibrations set up by the chopping
action of the the teeth of the saw blade.
....

But, a few ounces as compared to the rest of the mass isn't going to be
noticeable. I've never been able to tell any difference of note between
the two on the PM66. On a small contractor saw one might have a better
chance...

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