399 coating process: the surface roughness does not influenc e the quality of the coating adhesion significantly  but the electropolishing treatment redu ces the endurable revolutions in pin-to-disc test down to 20 to 30%  of the un-electropolished samples.   Influence of proper run-in on friction / torque 

Molybdenum disulphide is to an extremely high degree hygroscopic. While exposed to ambient atmosphere / humidity it absorbs water and binds it molecularly. Thereby the coating changes its  microscopic structure and friction increases. This pr ocess is not completely reversible by drying MoS 2 in  vacuum but mechanical pressure by performing a run-in has to be applied in order to get over this initial peak torque in the gearbox and ball bearings. Howeve r, evacuating throughout the weekend resulted in  better torque value instead of evacuating only over night; a proper run-in even increased the torque  margins.  This effect is not unknown in the technical world but it turned out that many exper ts are of very different  opinion how to deal with an MoS 2-coated actuator and that good communication with all suppliers was  necessary in order to sensitize every employee to this issue. 

Conclusions and Lessons Learned   The first flight model with the MoS 2 dry lubrication and Vespel SP1 bushing has successfully been  implemented into the Flight Model RMA. The RMA ha s performed its acceptance program and is currently  mounted onto the NIRSpec optical bench. Though the full qualification program at the end of 2009 is not yet finished we are confident of having supplied an actuator that will safely provide the required functionality throughout the lifet ime of the NIRSpec instrument.   During the very short time frame of the execution of this development program (7 months), we have  learned a lot both about development programmatic as well as about material and lubrication technologies. Some key lessons learned shall be outlined here - some of them not really new   Programmatic lesson learned:

1. Do not change too many technical parameters at the same time; it may be impossible to identify the  reason for both improvement and deterioration!   2. Postponing tests and planning to combine them with other tests due to programmatic reasons can  become a shortsighted decision. Both technical and programmatic reasons might eliminate the  possibility to perform the particular test at a later time. Certain measurement results can be generated only at one specific time and once this time fr ame is closed, the opportunity for measurement might  be missed forever.   3. Ensure that your suppliers are fully aware about the full story and their contribution to the  development success. This is a key success factor to  ensure that the suppliers provide their utmost  technical capabilities and are extremely flexible on necessary modification which are normal in such a development program. Access to the supplier's expertise can only be acquired if they feel as part of the team and do understand what the final applicati on of their contributed part is. As an example  Gysin (gear box) should be mentioned as they su cceeded to provide a gear teeth surface quality far  beyond their standard industrial needs by prope r setting of the standard machinery.     4. A success-oriented approach initially has the char m that it could save time and money but always  contains a high risk of failure with doubling the cost  at the end as the work has to be done twice. We  must confess that we had good luck that the sele cted combination of materials for the FM1 was the  right choice as this combination was found to be t he best as result of the pre-QM life test. In many  other development programs similar results could not be achieved.   Technical lessons learned:

1. MoS 2 lubrication might be seen as a state of the art dry lubrication. We lear ned that the processes  applied to the materials prior to coating do have a re levant influence on the sputtering process. Even  the sequence of processes seems to be of importance.  The initial loss of sections of dry lubricant on  NASA/CP-2010-216272