Making a player able to push a model?

I was trying to make a book case that a player an move around. I used a weld script and the parts are unanchored and won't move. I tried using the CustomPhysicalProperties Roblox added but, the player still couldn't push the modem bookcase. Do you guys have any suggestion on how I can fix this?

Josh

Are studs and inlets on the parts? they will connect them together, basically anchoring them. Make the density to 0 in the custom physics settings and voila! make sure the books and everything are welded together

You can just deanochor and it should move easier??