How was circle ceilings made in mid 1970's USA? Need to repair
I need to repair a patch in my ceiling. The house was built in the USA during the 1970's. It appears to be perfect circles made in the drywall mud (then painted over). Some sort of tool was used because you can see a tiny hole in the exact center of the circle. I have tried using a brush attached to a drill bit, that didn't work. The circles are the same size as an old record album and they overlap in a random pattern. I have tried googling to look for a special tool but nothing comes up. All of the drywall installers are younger men who have no idea, I guess the 'grandpas' who did this type of ceilings are dead, retired or not on computers. lol Anyone have an idea? This ceiling is 800 square feet so I am not going to re-mud a new pattern on it or cover it over. I like the ceiling.