Help please w/ programming a CNC machine

[djvass]

I know the answer to this is probably obvious but it's 30years since I used any geometry :?

I'm programming a CNC machine and need to position a saw blade for a specific cut.

With reference to the attached drawing. I need to find point G. I know point F. the parallel lines are 18mm apart, the arcs radi are concentric and always 18mm apart. point F doesn't move, point G moves along the inside parallel line as the radi of the arcs increase/decrease. I know the radi.

Does this make sense ?

 

[mmm4444bot]

I'm programming a CNC machine and need to position a saw blade for a specific cut.

Does this machine use an xy-coordinate system, to locate positions on the plane?

… the parallel lines are 18mm apart, the arcs radi are concentric and always 18mm apart. point F doesn't move, point G moves along the inside parallel line as the radi of the arcs increase/decrease.

I'm not understanding how d=18 does not change while F is stationary and G moves.

 

[djvass]

Does this machine use an xy-coordinate system, to locate positions on the plane?


I'm not understanding how d=18 does not change while F is stationary and G moves.

F is a reference point on a machine base so it's always known. d and R2-R1 are both 18mm, these are pieces of timber. I need to tell the machine to go to point F and cut to point G. If it makes things easier to understand both point can move. What I need is a formula for G given I know point F, R1, R2 and d=18 and R2-R1=18.

Anyone help ?

 

[djvass]

Does this machine use an xy-coordinate system, to locate positions on the plane?

Yes it uses XY.

Thanks

 

[stapel]

Just FYI: Becoming a CNC machine operator requires at least a couple years of training (here). It's entirely possible that a "mathematically ideal" solution posed by volunteer math helpers might not work in the real world of the machine shop. :shock:

 

[djvass]

Just FYI: Becoming a CNC machine operator requires at least a couple years of training (here). It's entirely possible that a "mathematically ideal" solution posed by volunteer math helpers might not work in the real world of the machine shop. :shock:

Don't worry about it, I've been programming CNCs for 30 years

I use C+ which allows me to use calculus, what I'm after is a simple geometric solution which I can use in G code and the operator can easily understand and manipulate.

Any takers ?