A few days ago one of FSwizard:PRo users questioned me over how FSwizard works.
The way SFM calculates seemed off to him.
As a result i made a quick sketch for him, that i thought i would share here.
Omar was asking me how come SFM seemed wrong for a 1" dia ball-nose cutter when making shallow depth cuts.
The sketch above shows exactly why.
On the left part we see a cutter engaged into the material to the depth equal to its corner radius.
At that depth the maximum effective diameter is achieved. So an old good RPM=4xSFM/Dia formula would apply.
But at shallower depths, effective diameter of the cutter is reduced.
At 0.1" depth of cut, effective diameter would only be around 0.6"
In fact it goes to zero at the very centre. So a higher RPM will be required to achieve the recommended cutting speed.
In the same thread i also explained how DOC/WOC balancing works.
So if you are interested - read on.
Here is the thread http://zero-divide.net/index.php?page=forums&shell_id=170&article_id=4590