Designed this cat tree pillar support thing because the pillar nut and it's surrounding material "broke". Been using it for more than a year, it survived my two cats that abuse it daily, it wobbles a little but absorbs the energy and I get to keep the tree longer.

I've included a sample stl you can print to figure out if it fits or you can calculate how much you should scale it for your tree if screw holes remain usable. Approximate dimensions are:
Diameter of the pillar hole: 92 mm
Diameter of the hole for the screw head: 9 mm
Diameter of the smaller hole for the screw thread: 5 mm
Height of the 5mm hole: 10 mm (so you can estimate how long should the screws be)

Other notes: I suggest printing with 20% infill, I used PLA. I added two horizontal screws just in case (see photos), but if you print it with a tight fit pillar should just drop in and use gravity to stay in place. Use wood screws that goo deep in the base, but don't come out below, also don't over tighten them.

Disclaimer: Use at your own risk I'm not responsible for any property damage or accidents. Every printer and settings differ if you print this without infill or don't have good layer adhesion for example don't be surprised if it breaks.

If you like my design and want me to publish more things consider tipping me via "Tip designer" button. I have a full time job that requires advanced computer skills, but don't earn a lot and any tips would be appreciated and would go a long way in supporting my hobbies which include modding, 3D printing, designing. Thank you in advance.