Yup. Too slow or too little chipload, rub the tool into oblivion or run into chip thinning. Too fast, and the unit melts and or breaks. The calculations can be done by hand, or you can use a calculator tool such as G-Wizard or
FS Wizard (has a web version).
G-wizard after one year subscription reverts to hobby use; meaning any spindle under or at 1HP is still allowed:
1 HP for life, unlimited HP for one year. G-Wizard takes into account stickout, materials, HP limiting, deflection, and several other parameters that are tedious to spreadsheet. Even with a calculator, fine tuning can and should be done. The basic requirement is knowing the tool chipload (how much material is carried away by each cutting edge). Turning, the chipload will depend on a the feed in surface feet per minute, but when the diameter goes down or up, the spindle has to speed up or down to maintain the same SFPM.
Another point to keep in mind when looking at Feeds and Speeds posted around the web on professional forums and or tooling sites: these are usually for production level material removal rates (MRR) on machines that weigh thousands of pounds, run multiple horsepower spindles and operate under the time-is-money-above-all-else rule of production machining, so take them with a grain of salt.
Basic Operations
To give you some examples of the parameters with drilling, Feeds and Speeds still apply, plus there are restrictions on drilling depth vs. drill diameter. Below a certain depth, the standard twist should be replaced with a parabolic type. Over a certain depth, peck drilling should be performed (which retracts the drill to clear the flutes and hole). Drilling certain materials requires changing the cutting angle of the drill tip, as does thin materials.
Examples with boring, account for the tool deflection (last cut should be run with no change in diameter to remove the spring in the tool).
Start with simple machining first, getting used to how the machine cuts, sounds. The operational envelope is determined by the machine, the material, the rigidity of the tool, speed of the spindle, run-out, cutting geometry, all items that generally can be ball parked, but then need fine tuning for specific situations and your machine. Get some aluminum, suitable cutting tools, and experiment. Listen, smell, feel the machine. Adjust speeds and feeds up and down and get sensory feedback on what is going on, you will quickly get a feel for it.
Resources
Here are some good starting places:
Stanford University Terminology: a PDF explaining some of the basic lathe terminology.
Little Machine Shop Calculator: Milling, Drilling, Turning
Little Machine Shop Cutting Speeds: Charts for same
Machinery Handbook:
The bible with 29 editions from 1914 to 2012. Pricey, but used and other copies exist. Think of it as the World Wide Web of machining in a book (with
over 2700+ pages, I feel safe in stating that). FAR more than you will need anytime soon. For example, from page 975 to 1264 in the 28th edition contains: Cutting Speeds and Feeds, tables, estimating speeds and machining power, cutting fluids, nonferrous metals and non-metallic materials, machine tooling accuracy.
Fundamentals of Machine Tools:
Section 7-5 has a good description and suggestions for feeds and speeds for boring.
Virtual Machine Shop: Has several articles and some animation about basic topics.
HERE is the section on boring, the
section on drilling.
Mini-Lathe.com: long running site with a lot of information on the various small lathes. Here is
Drilling,
Turning,
An enthusiasts beginner list: he is a native Japanese speaker, and some of his english transliterations are odd, but there are pictures enough.
Drilling,
Basic Lathe Operations
In fact, apparently that can cause a variety of problems like overheating, bad surfaces, shortened tool life, etc.
