I went to Menards to see what different kinds of tool they have for finding the center of a circle and all they had was the cheap "Tool Shop" brand. Something about the tool did not look right to my eye but I did not feel like driving to the other end of town to go to The Home Depot, now I wish I did. Remember, you always get what you pay for, and I do not recommend this $9.00 piece of Poo Doo. When I got it home I tested it out right away and noticed none of the lines I drew intersected in the same spot. I looked at the measurement device and noticed that the straight edge overlapped the center line point instead of riding on it. So I tried again, this time drawling 4 lines then flipping the tool over and drawling the same 4 lines again.
If you look at the lines on the circle none of them go threw the center of the circle, but by flipping the tool over and drawling the line again I got 2 parallel lines on either side of the center.So after drawling 4 sets of parallel lines I was left with a tiny white dot in the center. Weird huh!
So after fiddling with that cheap tool I found dead center and started drilling the wholes. Now if only the outer diameter of the pipe holders were perfectly round I would be good to go. LOL