machine speeds

[blackice]

Hello all

i am in the procsess of designing a cnc machine, and i am currently looking at linear actuators for the x,y,z axies.
my question(s) is this.......what are the average speeds on a cnc router machine? i was assuming anywhere between 80-100 ft a min but am i off my noggin with these numbers?
also because these units will come with motors supplied, does the software limit the speed the motors will turn (mach3 etc)? any help on this is appreciated

[ger21]

Velocity is usually measured in inches per minute (ipm). Average speed depends on a lot of things, generally related to cost.

You're 80-100fpm (960-1200ipm) is what I cut on the $100,000 router we have at work. The 15HP spindle is probably $15,000.

Trying to cut 3/4" deep at those speeds will just stall a low power spindle and snap the bit.

A lot of the machines you see here use either 2HP handheld routers or the more powerful (and more expensive) 2.2Kw chinese spindles. Most cutting is probably done in the 100-500ipm range with these machines.

Tooling, material, machine rigidity, and power all factor into cutting speeds. Look at a chip load chart from a tooling manufacturer to find ideal speeds for specific tools and materials. Whether or not your machine is capable of achieving those chip loads is another story.

[blackice]

hi ger

as you quite rightly pointed out cost is the common factor and money (or the lack of it) will govern the out come. i will check out the chineese spindles ( is there anything those inscruitable little men dont make!).

What do you think about driver motor speed being limited by the software that is controlling it? I would have thought this would not be an issue, but i am putting it out there all the same. many thanks for your invaluable input.

G

[ger21]

Forgot the last part.

In Mach3, you set the maximum velocity for each axis. This speed is used for rapid (G0) moves. Cutting feedrate is set in the g-code with the F word, F100 would be 100ipm (or 100mm/min if using metric).

[blackice]

thanks gerry

gabriel