Circles/Angles

Hi,

I'm trying out L.cad to determine XY co-ordinates for a CNC drill to drill holes in round rotors. (Until now, I've been working out the co-ordinates via sines and cosines in a spreadsheet, and then creating the g-code program by hand from the numbers. Now to make a change I have to do it all over again.)

What I'm trying to draw/find seems simple enough...

1. circle with 4" radius (1 inch in from edge of 10" magnet rotor)
 2. 9 circles of 1" radius evenly spaced around this circle (motor coil positions)
  3. three points within each 1" circle (for mounting bolt holes) at .375" radius, at the outermost point from the main circle center, and 120 and 240 degrees from that.

I can draw the first (4" radius) circle fine. When I go to draw the 1" radius circles they snap to center on the  edge of the first circle (cool!), and I can see the angle in a box at the lower left, but there are fractions and I can't get it to exactly 40, 80, 120... degrees. Nor do I see anywhere to enter the angle numerically. After the circle is made, "properties" shows the x,y co-ordinate of the center, but not the angle WRT the first circle/origin.

Is there any way to get the 9 circles at the exact angles around the first one?

If so, I can try to get to step 3.

Thanks,
Craig

rotor.dxf

Hi Craig,

I uploaded a dxf file according to my understanding of the drawing you asked.

steps to draw it (with 2.0 series):


0, start LC with an empty drawing;
1, Main menu: Edit->Current Drawing Preferences->Units : set "Main drawing unit" to "inch";
2, Main menu: Draw->Circles->Center,Radius (or use main cad tool bar);
3, Set the radius value to 4 in the input area shown by step 2, within the toolbar area;
4, Spacebar or click to activate command line, type in coordinates for the center: 0,0
Press Enter to accept the command and draw the circle
5, Set the radius value to 1 similar to step 3;
6, in command line, type in coordinates for center: 4,0
to draw the circle;
7, Set the radius value to 0.375;
8, in command line, type in coordinates for the center: @1,0
to draw the circle
9, Main menu: Modify->rotate , to start rotation
10, when prompted, select the circle drawn in step 8, with radius 0.375 , and click the right pointing arrow to accept the selection;
11, when prompted for rotation center, type in command line: 4,0
12, when prompted for reference point, type in command line: 5,0
13, when prompted for target point, type in command line: 4,1
please note 4,1 is not according to 120 degree here, and we basically entered a random number here, because we are going to specify the 120 degree in the next step;
14, when the rotation options window shows up after step 13, modify the Angle(a) to 120 , and check the radio box "Multiple copies", type in 2 within the input area of the multiple copies; click ok to rotate.
15, repeat from step 9 through step 14 to rotate the r=1 circle and the the three r=0.375 circles together with 8 copies, Angle(a)=40, around center 0,0



dxli