taylors tool life equation

[davey101]

Hello all,
New member here looking for some help. I have been trying to find information on taylors tool life equation preferably in the form of a book to no success. if any one could help me to identify the equation T=CV^n I would be very gratefull. In particular with refernece to the n and C values.

Thanks
Dave

 

[tomwalz]

n depends on tool material
C depends on workpiece and cutting conditions


Thomas J. Walz
Carbide Processors, Inc.

http://www.carbideprocessors.com

Good engineering starts with a Grainger Catalog.

 

[davey101]

thanks tomwalz,
Maybe i should have explained it better in my question. Its the actual value of n and C i am having trouble locating. I cant seem to find a table or graph from which they are derived.
Is there such a table or graph? Has the n value something got to do with hardness of the cutter?
I am having no luck with this and i get the feeling it will be staring me in the face all the time.

Anyway thanks for your help

 

[tomwalz]

I have never found Taylor's equation to be particularly helpful. However a great part of what we do is design special tooling such as saw blades, router bits, etc., for specific applications such as plywood plants, MDF plants, sawmills and so on. To make Taylor work, in my understanding, you need to establish a couple of reference points. Then Taylor gives you a formula that lets you approximately derived values by interpolation or, perhaps, extrapolation.

In my world we look for an optimal solution based on current materials, both the material being cut and the material used as a cutter head. In a situation, such as a Boeing plant, where you are using an identical cutter head material with different grades of aluminum; Taylor could have some value once you know how the different grades aluminum perform.

Another consideration is the fact that at this level of machining a good operator needs to be sensitive to variations between parts of what are supposedly identical pieces of material and variations with in a particular piece of material


Another factor that I find limits Taylor's usefulness is the desire on the part of the plant operator to make improvements without making changes. Cermets have a higher lubricity than carbide and can show dramatic improvements in cutting life if they are run faster. However any gain in cutting life may be more than offset by the difficulties of increasing the feed in a sawmill, for example.


Thomas J. Walz
Carbide Processors, Inc.

http://www.carbideprocessors.com

Good engineering starts with a Grainger Catalog.

 

[racookpe1978]

A thing to that Taylor doesn't allow for:

The quality and quantity of a machinist's performance depends on his machine and his tooling.

The quality and performance of a machine tool and its tooling depends on the quality and performance of its machinist.

Taylor assumes both are "nominal" and "consistent" and predictable. Shift to shift, the same man can make a bad tool wonderful, and a good tool terrible.

But remember, I work in the field under non-toolroom conditions and short schedules, so the machinist's skill outranks the standard designs needed in a production line.