CNC G code - volkswagen logo

[eric_spelon]

hey guys, i had an assignment appointed by my lecturer, but i have 0 idea on how to do it wasn't really clear of what the lecturer explain about the coding, and have been trying out many many times but still fail i'm given a 9cm by 9cm workpiece to do it, have to milling the VW on it any of u guys can help me on this? i'm really deperately need help i've attach a 2d model which i drew in my inventor, can help me on the coding part?i'm dead

[dcoupar]

What machine/control is this for?
Do you want to use an engraving tool or small end mill?

[dcoupar]

Here's a program for a Haas.

[eric_spelon]

thanks alot for the info.. i'm suppose to do a G coding, on a small machine with only 3-5 cutting tools for milling only

[eric_spelon]

is there any simple coding for this?? because we're stilll new to this and just learn it in lecture class, never learn about engraving yet.. i need a simpler coding for milling anyone can help me? thanks alot guys can u help me, dcoupar?? i really appreciate your help so so muchthanks alot

[dcoupar]

Originally Posted by eric_spelon is there any simple coding for this?? because we're stilll new to this and just learn it in lecture class, never learn about engraving yet.. i need a simpler coding for milling anyone can help me? thanks alot guys can u help me, dcoupar?? i really appreciate your help so so muchthanks alot

Sorry, that's as simple as it gets. Engraving is just milling.

[eric_spelon]

Originally Posted by dcoupar Sorry, that's as simple as it gets. Engraving is just milling.

okie okie thanks alot dcoupar u really helped me alot god bless once again, a million thank you again

[rowbare]

I can understand being stuck but you aren't going to learn anything by having others to do your homework for you.

Are you supposed to use CAM to generate the GCode or write it by hand? This is a pretty simple logo so, assuming that you aren't going to pocket it, you should be able to write this by hand in about 21 lines of GCode not counting Z up and down or rapids (assuming you aren't cutting the enclosing square).

This is what I would do (assume the centre of your drawing is 0,0).
1) Describe each of your components in terms of coordinates. For example the enclosing circle can be described as:
an arc of radius 4.4 cm centered on (0,0)

The top pie slice can be described as follows:
a straight line from (0,1) to (-1.2, 3.4)
an arc from of radius 3.6 cm from (-1.2, 3.4) to (1.2, 3.4) centered on (0,0)
a straight line from (1.2, 3.4) to (0,1)

So from there you can start writing gCode. Using the two above examples:

Draw the circle:
G0 X-4.4 Y0
G2 X-4.4 I4.4

Draw the pie slice:
G0 X0 Y1
G1 X-1.2 Y3.4
G2 X1.2 I1.2 J-3.4
G1 X0 Y1

Note that this doesn't include any preparatory moves, Z moves etc... but it should be enough to get you going. Simply repeat the above process for all of the components.

Good luck!
bob

[hub]

As this is an assignment you want to understand and learn.. So I'm not posting the G-Code for a copy - paste But I can give you some ideas on how to do it.
(I'm assuming manual coding)

- Look at it and split it into (in your mind):
* Lines
* Circles
* Arcs
- For each LINE; it has 2 points. Start and end. Check the coordinates for each point. Then write code to go from point 1 to point 2.

- For each CIRCLE; it has a center point and a diameter. You have 2 options; either drill or mill (in this case mill). Write the code knowing center point and diameter.

- For each ARC; it has a center point, a starting point, an end point, a start angle, an end angle and a diameter. Check/calculate those necessary, and write the code.

[dpuch]

An expansion on what rowbare and hub offered.

Your dealing with a 3D XYZ cartesian coordinate system. Your image is showing the logo in the X and Y axis with Z being up and down. X plus is to the right. Y plus is to the top. and Z plus is up out of the image.

G0 is a rapid move (non cutting)
G1, G2 and G3 are modal feed moves that require a feedrate at least once on or befre the first one.

G1 moves in a line from the current position to the X Y Z position given
G2 is an clockwise arc from the current position to the X Y Z position given with I J K as the center of the arc (I is an X axis value, J a Y and K a Z)
G3 is the same as G2 but counter clockwise.

Follow rowbare's suggestion and figure out you points. Arc/line endpoints, and arc centers. Then start putting them into a g-code format.