You'll want to be able to tightly clamp the frames in the press, and therefore it is critical to the longevity of your frames that the clamps not excessively mar the frame. "Chewed up" frames are very difficult to align properly and of course, won't maintain their structural integrity as well either.
Teeshirtprinters.com uses a nonmarring clamp design. As you'll see, the clamp bolt extends through the top of the screen clamp and ends in a nut with a free rotating cupped washer. This design offers several benefits over the common design consisting of only a clamp bolt.
As you tighten other clamps, the rotation of the bolt in contact with your frame results in one of two things, depending on the type of frame you're using. Aluminum frames dent, gouge, and get ugly scoring. On a wooden frame, the effect is like a drill, and the result is a deep pocket in the frame. Even worse, squeegie pressure during printing will continue to deepen the holes, eventually affecting the register of the job.
The
design of the Teeshirtprinters.com screen clamp distributes the force of the
clamp over a much wider area. This allows more clamping force than is possible
with inferior designs. Additionally, since the washer portion of the clamp bolt
assembly is free-spinning on the bolt, no rotation of the portion actually contacting
the frame occurs during tightening. While pressure will leave some sign of the
clamp, there is no gouging or boring of the frame, and your frames will last
almost indefinitely!