I remember a thread where someone made a plate out of perhaps aluminum.
It was designed to sit in the bottom of a Lee pot.
There where holes drilled in it to hold jackets upright.
It was made to bond numerous cores at once.
It had a bolt for a handle in the center of the disk so you could lower it into a pot and remove when ready.
I’d really like to find the thread because it had a great picture, but I’m not having much luck. A point in the right direction would be most appreciated.