Gravity testing

So I have some designs I want to try out their stability, does it make sense to import to Blender and use the gravity there?

If you're talking about doing a simulation then perhaps one of the Blender experts here could give you a good answer on that. Myself, I always go straight to Sketchup's Sketchyphysics plugin for doing 3D simulations. Because it is free and super simple to use!

OK cool! It works with the free version of Sketchup?

Yes it does, it's completely free. You can also download thousands of Sketchyphysics simulations that others have created in the Trimble Warehouse for free.

Also worth mentioning when it comes to free physics simulation is the 2D super easy to use Algodoo. Algodoo was a freeware software program known as Phun years ago, which became super popular and then the name was changed to Algodoo and it was made commercial, but then everyone abandon it and so they just recently made it completely free again. Algodoo is mainly for just goofing around and quickly finding the solutions to things, but one can do serious simulations with it if one gets highly into the workings of the software. Another free 2D software similar to Algodoo is Physion, which I've used as well.

Since your avatar shows a solar system diagram and your thread is about gravity simulation, are you wanting to simulate the motion of planets? If so, you may be interested in Universe Sandbox. It's not free, but it only casts $10 US purchased from Steam. I used this software years ago to simulate the motion of comet Elinin that I was wanting to know some details about. It's extremely good for doing simulations involving gravity and not too complicated as well.

It's for my solar system models, I want to make them more modular, but I also want to make sure they can stand on their own without crazy bases or support struts. Thanks for the suggestions, I'll run it through a few of them and see which gives me the best results!

Oh ok, I see. Yeah, for that I'd definitely go with Sketchyphysics.