Red thumbscrew vs black thumbscrew

[Chopper]

My original black ones started failing a few years ago on their own...I never remove them. The set I ordered came in red, so I threw them in a drawer and bought a length of wooden dowl (Johnny Apollo gave me the idea) and glued it into the black broken ones....Good as new!!

[VX KAT]

I glued a wooden dowl inside the screws...super strong now

and bought a length of wooden dowl (Johnny Apollo gave me the idea) and glued it into the black broken ones....Good as new!!

I'm going to do the dowel mod before mine break.
Did you use a dowel wide enough so it was a snug fit or slightly thinner so the glue doesn't get scraped off as you inserted it?