Yes, you can use single screen dry sift, absolutely! Consider the old-school methods up in the mountains of some place like Afghanistan or Nepal. Basic, handmade, simple sifting with screen and pressing with bricks. There are modern methods of-course, but to try it out, first time or two, give it a try. I started making hash this same way, experimenting with pressure and heat using dry-sift kief. It's the simplest, cheapest way to try it. Using multiple finer mesh screen gets awesome results and different 'grades' of kief. Finer grades produce better product, but even single screen dry-sift can be most enjoyable and worth the effort.