On Apr 30, 8:54*am, Chris Wilson wrote:
My maths is appalling, I am sorry to say. Yesterday I wanted to work out
the X and Y axis movement on a milling machine to drill two holes opposite
one another skewed 45 degrees from the vertical at a known PCD . I had the
machine zeroed on the centre of the hole around which these drillings were
needed. Took me ages as I have forgotten most of my Trig and I couldn't
find a suitable calculator Is there any easy to use engineering software
for this sort of thing? It's at times like this a CNC machine seems
wonderful Ta!

A cheap CAD package would probably do it, or a little work with
memorizing what the trig functions REALLY mean along with a dollar
store "scientific" calculator would do as well. I've picked those up
for as little as $6 from Big Lots. I find the calculator is faster
for most things. Holes in a circle might be the break-point. It also
helps to know that the length of the hypotenuse of a 45 degree right
triangle is the square root of 2 times either side in length, a
special case along with a 30-60-90 triangle. See Pythagorean
theorem. From that it should be dead easy to work out X-Y, even with
a pocket four-banger calculator. Banging away at problems 5 days a
week at 7:30 in the morning for a couple of years will embed this
stuff permanently.

Stan