Oh as in everything emits its own gravity? Thats not a part of tpt, the only particles that can emit gravity fields are BHOL WHOL and GPMP. Sorry man.

thats because "gravty off" only stops global gravity. particle-to-particle gravity with the exception of a couple special particles is not yet implemented; so mass of individual particles and AOE isn't calculated(yet).

the closest you can get so far is to use something at the core that uses either presure or gravity firelds (WHOL,GPMP,etc) to attract things. no amount of sand will simulate gravity like real life.