2012 Annual Report 1a.Objectives (from AD-416): To determine lint cleaner settings or design parameters that will. 1)improve the removal of seed coat fragments from the lint,. 2)possibly allow separation of small seeds that pass through the gin ribs from the primary waste stream,. 3)reduce short fiber content, and. 4)reduce nep content. Related to seed coat fragments, this project will also work to document the ability of a cottonseed shear tester to rank varieties in terms of their potential to form seed coat fragments. 1b.Approach (from AD-416): Some recently released cultivars have a fragile seed coat that breaks easily during harvesting and gin processing, and contaminates the lint with fragments of seed coat material. Seed coat fragments cause major problems at the textile mill. Because the cultivars are relatively new, there is no current research on their interactions with harvesting and gin processing. Current research will attempt to remove seed coat fragments, and improve fiber quality attributes such as short fiber content and neps, with newly designed lint cleaner grid bars, a newly designed lint cleaner air-knife grid bar, or newly designed pneumatic fractionator in place of the saw-type lint cleaner. ARS brings to the collaboration scientists and research ginning facilities, while Cotton Incorporated brings scientists and fiber test facilities. Both organizations will gain a better understanding of interactions between seed coat fragments and gin processing. It is hoped that this research will provide domestic and international textile mills with a better quality fiber. 3.Progress Report: A study was done to observe how very small amounts of fiber and seed coat fragments (SCFs) reacted after colliding with lint cleaner grid bars. A high-speed video camera recorded the collision. A control and experimental grid bar were used in the study. Results showed that the experimental grid bar was more effective than the control grid bar in removing SCFs. The results of this study were presented at the 2012 Beltwide Cotton Conferences. Another study was done using larger amounts of fiber and SCFs and included six grid bar designs (five experimental and one control) and two types of cotton. The cotton included a common upland cultivar, and a cultivar known to have a fragile seed coat that breaks easily and contaminates lint with SCFs. Fiber tests will determine which grid bar(s) removed the most SCFs. This RCA with Cotton Incorporated is a continuation of research from 2011. This research will be the basis for a future journal publication. Communication between Cotton Incorporated and the ARS PI occurred by telephone and e-mail on a monthly basis, and at industry functions such as the Beltwide Cotton Conferences, the annual meeting of the American Society of Agricultural and Biological Engineers, and various state ginners meetings.