Newbie- Question bout feed rates

[MynamesKenny19]

Hi guys, I have a question for you that isn't in my textbook for college and has been bugging me.

When a CNC mill is going to take a cut from the side, does the feed speed matter? That's a bad way of putting it, so heres what i mean:

some cnc mills, when they make a cut, they accelerate into the cut until they get to the required feed speed. What effect does this have on a tool compared to one that enters the cut at a given speed instead of accelerating into the designated speed???

Haha, I'm sure I overcomplicated a simple queston, just my mind can't put my thoughts into words that make sense lol.

Thanks for taking the time to help me out =]

[BrandonB]

I personally have not seen a machine that will work its way up to a feed rate but i am not sure about that. I have seen people rapid close to a part and then start a feed rate. As far as i know once a feed rate comand is given it is at that feed rate till changed and you can change a feed rate at almost any line in a program. Side cutting you can run higher speeds and feeds than if you were pocketing or something like that. Not such if i helped i am the same way i know what my brain is thinkin just hard to type. Good Luck

[78nova]

I agree with Brandon, I also have not seen a machine work its way up to a feedrate. I have seen machines that can be programmed to slow down in the corners and then resume the programmed feed. The speed and feed should be set to the cutter used and setup and material being cut. Side cuts as you called them will work basically the same as all other cuts. When pocketing, I like to bore straight down into each corner and then come back and mill around the sides when it is appropriate. This really helps when your finish and width dimensions are tighter. You may also find that ramping into the cut when side milling will give you better tool life. What I mean by ramping in is to make a 2 axis move to get over to your starting point instead of just going to an X-Y-Z position and then just make a move down or over to enter the material. If you stage your tool up off to the side and then program an X-Y move to make your entry, it will perform better. This is a little more work but if you are machining harder material it can make a big difference, especially when using inserted tools.
Hope this helps some. Later