Ok, my new legs work ok for my poker table, but the screws have a tendency to pop out if there is too much sideways pressure.... it's too-thin particle board

I want to glue plywood to the bottom and screw the leg holders into that, and the original table

Anyone try anything like this before, and is there a risk of the particle board failing and disconnecting?

I would have to see the tables proper to give you an opinion, but it would seem that the best guess is to remove the poker surface from the legs and attach is to a separate, more sturdier table. Attach velcro to the bottom of the poker surface and the top of the table and BAM, instant sturdy table.

You should be fine gluing plywood to the particle board as long as you make sure the plywood is about 1/2" thick and oversized. If the table legs are 2" diameter then you want the plywood to be 4-5" squares. However this will not work forever. The problem with screws is they are not meant to be removed and put back in because they'll take bits of wood with them and ruin the original holes.

What you really want to do is swap the screws with bolts and mount a nut into the plywood after drilling a hole through the plywood. You won't have stability issues once you do this.

In order to go through the table, I need to go through the felt surface... I am opposed to that for asthetic reasons.

I was thinking of a plywood piece slightly smallet than the table, with wood glue liberally applied and many screws holding it to the particle board, then screwing the legholders to the plywood with screwslong enough to go into the particle board as well. Yes, it adds a good deal of weight, but I am Strong, Vigorous Man (10 points if you get that movie reference)

I guess I wasn't very clear with what to do with the bolts. I meant you should mount the bolt to the center of the table legs and then screw those into the nut you have mounted in the plywood. You can get bolts of a size that won't require you to drill a hole all the way to the felt. This would also make it so you don't need to carry around a screwdriver in order to put your table together.

I also wouldn't mount a piece of plywood that big to the table because it'll cause problem when you try and fold it up and put it in the carrying case.

The table legs are from Ikea... they have metal brackets that are screwed into the table and the legs screw into the brackets

Without seeing anything:

Particle board is not the greatest material, but i you use wood glue and sufficient clamping pressure (a LOT of clamps I am guessing) to join your two surfaces you should get a good bond. Add screws afterward; they will interfere with the gluing.

Thank you for the suggestions. I will get my ass in gear on this soon