crazycage

if you want to machine a piston and you no its got a 7.2cc dish in it and you want it down to say 14cc how do you work that out into a material thickness?
thanks gary.

Nash_mr2

with a complex course of mathematics, calculations measurments and an awful lot of head scratching.........or just whack it on a CNC machine and let that do all the work.

crazycage

i could put it on a cnc right now but it still needs to how much to take off lol

oohogwash1

If you make some assumptions I think its not too hard. And if you make a calculation based on planing x amount and keep calculating till you get what you want that would be relatively easy.

Its all high school math for volumes of circles and easy to put in a spreadsheet... Its what I can remember anyhow

If you measure the outermost diameter and the innermost diameter of the dish and the depth of the dish you can then calculate the volume by many ways here is two easy ones.

Assuming the gradient of the dish is consistent across the dish.

If you also assume the angle was 45degrees (which it probably is not) you can get a rough idea of the depth by simply using the average diameter of the inner and outer surfaces using your volume of a cylinder calc from high school.

To get more accurate then an easy way is to measure the volume of the centre diamer circle and then calc the volume contained in the gradient area, to get the gradient volume take the average calculate the area of slice across the gradient triangle using the diameters you measured before (1/2 of a rectangle from diff of radius's times depth) then multiply the circumferance of the average diameter circle you measured above...
They are not dead accurate but should give you a rough idea...

pa_sjo

I wouldn't say that is particularly complex mathematics!