The first year we planted clover we did not have a cultipacker. We we had two very large steel doors (fire doors) from an old school. We dragged them around behind our trucks once prior to planting the clover, and one again after. We tried weighting them, but the cement blocks kept coming off, so we finished with no additional weight. They were 3-1/2' x 8' and weighed about 100-150 lbs each, we had the tied together with chain. They did a great job leveling the field and pressing in the clover seed. The important thing is to get good soil/seed contact, and reduce air pockets in the soil. You know that when clover germinates, its very small, and the roots are hirlike, if they grow into air pockets in the soil, they die back. Too many air pockets, and you do not get a good stand. This is probably the largest reason its importand to seed just before a rain, a good rain helps to compact the soil and set the seed for excellent germination.