drawing problem ,

[riah]

[CyberAngel]

How far should the centers of the radius-10 circles be from the center? In other words, how do you place the tabs (or whatever you call those circular protrusions)?

 

It looks like the left and right sides of the central tab are different. Should they be symmetric?

 

Once you place the tab circles, you should be able to draw the radius-4 circles as tangent to two of the tabs. Then it's just a matter of trimming.

 

Here's what I got with the tabs placed on the diameter-80 arc:

 

 

[eldon]

I would start by drawing five circles R10. Then two circles R4 using TTR.

 

Then trim to suit.