# Hole drilling problem

#### RBR1317

Joined Nov 13, 2010
595
"...is designed to have seven speeds."
"...determine the six spindle speeds..."

So have you determined whether to find the 6 or 7 speeds?

#### LesJones

Joined Jan 8, 2017
2,845
Start by working out the minimum and maximum speeds required. Post your result and we will tell you if you calculated those two values correctly.

Les.

#### Picbuster

Joined Dec 2, 2013
1,025
Hey Jonas,
did you end up finding the answers to these questions? i have been given the exact same ones, they are difficult!

A drill will cut x mm per rotation this will produce the max speed to move into the material.
However; type of material will consume power so the cutting edge will produce heat.
Now you have to look into the table from the drill manufacturer to find the max speed in relation to the material.
This will produce meters per minute. The diameter allows you to calculate rotation per minute.

Now you are able to calculate the allowable speeds ( two values: refs per minute and max speed to move into the material.)

The same will apply for milling in x,y and z axis.

That's all.

Picbuster