I am designing some gears and need a way to put a flat surface on the center hole. The motor the gear will go on has a flat on the shaft where a set screw matches to hold things firm. So I need some way of making a circle with a flat side.

Thanks.

Hello

If You could share screens of the SVG file, or just a sample file of what are you trying to achieve.

My "clueless guess" is that You are tryng to make an isometric drawing, and trying to centre all in an axis. Well, my experience is that you have to use the transformation dialog, and guides and snapping. Use auxiliary objects like lines, circles or rectangles that points to the elements you want to arrange.

Please, If you find the answer share here the results

If you want to 'flatten' one side of a circle, take a look into the boolean operations.
My guess is that you want to create something like this:



To do so, create a rectangle and a circle, put the rectangle above the circle, select both, then do 'Path -> Difference'.