I'm building a disk, of uniform density, which will be spun at a constant
RPM about a central axis (ie, a flywheel). It's actually a little more
complicated by several short carbide rods inserted perpendicular to and
towards the periphery of the disc surface (metal content), but for now I'll
limit this to the disc itself.

Since it's been too long for me to remember (or be able to derive by myself)
any calculus, does anyone have any handy dandy equations useful in
determining the tensile forces in a spinning disc? I know the tensile
strength rating of the material, and would like to be able to safely "rate"
the spinning thing to be within a safe (70% or so) margin.

Thanks for any suggestions,

Jon

In article ,
says...
I'm building a disk, of uniform density, which will be spun at a constant
RPM about a central axis (ie, a flywheel). It's actually a little more
complicated by several short carbide rods inserted perpendicular to and
towards the periphery of the disc surface (metal content), but for now I'll
limit this to the disc itself.

Since it's been too long for me to remember (or be able to derive by myself)
any calculus, does anyone have any handy dandy equations useful in
determining the tensile forces in a spinning disc? I know the tensile
strength rating of the material, and would like to be able to safely "rate"
the spinning thing to be within a safe (70% or so) margin.

Simplified formulas are in Machinery's Handbook in the
section on flywheels. Roark's has more in depth coverage.
Mark's should have something as well.

Ned Simmons

Anything inserted through the disc, especialy near the rim,
will constitute a 'stress raiser` as well as the obvious imballance
and have a larger than expected effect.
Any 'safe rotation speed` that you calculate by a general method
will be far higher than the actual safe speed.
Better to use 50%, - and even that may be too much .
MadDog

Machinery's handbook will be conservative in it's recommendations,
which is a good thing. Their formula has some good size safety factors
built in.

If you need exact formulas let me know. They're fairly simple. I can
scan them into a pdf file.

Bruce