Turning Speed for Aluminium

As a general rule I run the spindle speed (milling) as fast as the machine will go if machining an aly billet that won't flex and has plenty of meat.

On the lathe the same is true for the smaller pieces you would likely use in slot cars.

Preferably coolant, (but WD40/kerosene will do) is a must, especially for doughy grades that don't machine well.

Speeds and feeds need to be altered if you get chattering due to thin/slender/unsupported sections and there is no text book to tell you, that comes down to experience, feel and knowing your machine. Order of operations is another important consideration on more complex parts.

- Cam

QUOTE (howmet tx @ 9 Oct 2012, 16:10) <{POST_SNAPBACK}>Can your machinist explain in layman's terms how you work out the thread of a given bolt, etc, in order to tell unhelpful people behind the counter (or on the I'net) precisely what you want? Something I NEED to understand, but I am woefully ignorant (my wife made me say that).

The shame... a man who love the Smiths but doesn't know Whitworth from metric.......

You need a thread pitch gauge, a pair of verniers and a data table or engineers book.
Measure the pitch (or threads per inch) of the thread which will tell you if it is imperial or metric, measure the OD of the bolt and refer to the thread table to tell you what it is.

- Cam