Originally Posted by HomeMadeCnc  If you cut and paste from Office it makes everything lowercase, interesting. . . . . |
No, it doesn't. It's a forum issue.
Optimum speed has more than one answer. Do you want the optimum speed to maximize tool life, or cut quality, or production volume? Manufacturers of good quality tooling will give a recommended chip load, which will give you a feed rate at a given rpm. Your machine may not give an acceptable quality cut at this chip load, so you might have to slow down. Or, your machine may not have enough power to achieve the recommended chip load, so you may have to take multiple shallow cuts, or slow down. If your machine has plenty of power, you may be able to exceed the recommended chip load. Bottom line, is to use recommended chip load as a starting point, and adjust up or down to suit your machine.
Is it faster to make multiple passes? If you're machine can handle one pass, that would probably be fastest. If your cutting particle board and mdf, a good quality compression bit would probably give you the quickest cuts.
Also, tool type plays a big part in how fast you can cut. You mentioned 1/2" straight endmill. Do you mean a metal cutting endmill, a two flute carbide tipped straight bit, a spiral router bit? A spiral bit will cut faster than a two flute straight bit. A three flute spiral even faster. A spiral with chipbreakers even faster still. Tool sharpness plays a part here too, as a dull tool will require more power from your spindle.
This question gets asked a lot, and it's almost impossible to answer, but I use one general rule which covers most situations. Cut as fast as your machine will allow, and still give you an acceptable quality of cut.