Model Union Plugin


This is a simple plugin that allows you to union all similar parts (i.e. same material) within a selected model.

Disclaimer: This plugin does not reduce lag and on the contrary is likely to increase it instead as unions are slow.


How To Use

This plugin is pretty straight forward. Open the plugin window, select the model you want to union, and press the big green button that says “Union”.

Things to Note

  • For bigger models, the plugin may freeze studio for a decent amount of time, so patience is required. Note the print messages in the output window.
  • For bigger models once again, some unions may be made with too many faces for Roblox to handle, deforming the unions and overall breaking the model. You should be able to Ctrl + z any model union you do, but if a model doesn’t union how you want it to, there’s not much you can do about it, as it’s not a perfect plugin.


Enjoy the plugin! I don’t know if it does anyone any good, especially after learning that it doesn’t work like a lag reducer quite like I thought it did, but nonetheless it still exists.

Plugin Link


At the top, recommend the user to enable the CSG V3 Beta. It generates better geometry and is quite faster than the current CSG V2.

1 Like

Wouldn’t say this optimize lag. It just creates more lag. But good for more Parts which don’t need to have CanCollide = true

1 Like

Hm. Just because of the more complicated collision calculations or what? What makes it laggier exactly?

I’ll look into that and see if I can add it.

Using unions like this is a bad practice. You’re likely better off using parts than unions.


It has terrible topology, and a billion other benchmarks of unions beinf slower than meshes and parts.


Huh, alright. Thanks for the advice.

1 Like

Alright, I’ll keep that in mind from now on. Before now I just assumed “less parts is better” meant that unions reduced lag, but I guess I didn’t consider the details.

1 Like

less parts does not always mean more better

More lightweight does not mean more better

Would you rather a whole briefcase, with little money (more lightweight) or a whole briefcase which has much more money?

Yeah alright. I edited the post to avoid spreading false rumors or anything.