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• The weekly telecon was held with ORNL again this past Monday.  Reiersen reviewed progress against our current top-down schedule. 
• Gettelfinger reviewed the results of the preliminary screening of high friction surfaces (PPT, XLS).  His conclusions were as follows:

  G10-on-SS and SS-on-SS both exhibited a low COF (<0.25)

  "Light" versus "Standard" nickel binder made no change (COF=0.53)

  CTD540 was marginally better than Stycast (COF=0.51 versus 0.46) and easier to use

  Larger (12 mil) diamonds marginally better than smaller diamonds (COF=0.56 versus 0.51) but may make dimensional control more difficult

  CTD540 appeared marginally better than the nickel binder (COF=0.56 versus 0.53 with 12 mil diamonds).  The diamond coated surface appeared unchanged in the post-mortem for the nickel binder.  The diamond particles appeared loose in the post-mortem for the CTD540 binder.  The relative permeability in the nickel binder was 1.7-1.9.

  Depositing the diamond coating on a 4mil grit blasted sheet of SS with a nickel binder provided marginally better performance (0.55 versus 0.53) than the same coating applied to the thicker bar.

  Future screening tests with focus on using CTD540 (no permeability issues) and smaller (6mil) diamonds (easier for dimensional control).  The configuration issue of using a separate high COF SS gasket or depositing the high COF material directly on the shim needs to be addressed.  The shear strength of a glass-epoxy joint will also be addressed in the next round of testing.

• Paul Fogarty presented a concept for measuring the eccentricity of a stud in a hole.  A gage measures the minimum wall thickness of the bushing.  Once known,  a 2" G11CR bushing can be put in a lathe and taken down to the correct OD.  It would be fitted by press fitting or gluing.  The concept was very well received.  He later went out to the test cell to try it out on the actual coils with the FPA technicians.
• Len Myatt provided an update on the shear loads in the bolted joint using a nonlinear model with friction.  He concluded that with modest friction, shear loads on the bolts would be low except for a few holes where a high coefficient of friction would be required to prevent motion.  When friction is present, the shear loads take the stiffer friction path.
• The PDR for the bolted joint has been postponed.  A meeting will be held on Friday to [1] adopt a design methodology and design criteria for the bolted joint based on HM Fan's paper which was circulated for review; [2] determine what additional bolts will be added and where high COF shims will be installed on the inner leg; [3] establish a reference bolted joint geometry which is consistent with tool grip needs for pre-tensioning the bolted joint and providing UT testing to ascertain the preload; and [4] establishing the material properties to be used in evaluating bolted joint performance. .  These things must be done prior to assessing the worst-case shear loads and evaluating bolted joint performance which would be reviewed at the PDR.  The PDR is expected to be held in two weeks around February 14.
• Drawings are needed to prepare the Stellalloy specimens for the bolted joint tension and shear tests.  The Stellalloy specimens will be cut from the prototype winding form.  ORNL (Williamson) agreed to generate the drawings.

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