With the past 18 months, two conditions have been discovered that can lead to loose jack screw connections when mating to the Gemini series Drive I/O connector. The symptom is that the jackscrew may push all the way into the threaded receptacle rather than tightening down via the threads.
First, somewhere around Fall of 2012, our connector supplier has brought a new production plant on-line and the connectors out of this facility tend to be slightly larger diameter holes, though still within tolerance specs for the hole sizes (which are M2.6 diameter).
Second, roughly 18 months ago our primary cable vendor for most of the Gemini family cable accessories incorrectly replaced the original M2.6 diameter jackscrew with M2.5 diameter jackscrews.
The M2.5 is the wrong size screw for the standard Gemini Drive I/O connector, which is an M2.6 diameter threaded hole. However, in many cases the M2.5 size will work ok in tightening down the connector due to tolerancing in the connector threaded holes and the cable's jackscrews.
In the worst case scenario, with a connector having slightly larger diameter holes with the undersized M2.5 size jackscrews the threads do not engage with one or both of the jackscrews. The threaded holes on the connector itself have been found to be within tolerance in these cases, but on the high side and not as forgiving of the incorrect M2.5 size jackscrews.
For all Gemini series cable accessories, Parker-EMN has redesigned these cables to make use of a machined jackscrew of the appropriate M2.6 size. The design is based on the jackscrews originally found in the GFB-KIT accessory with the jackscrew barrels extended to make finger tightening more feasible (these are also now used in the GFB-KIT as well).
In the event you have a Parker Gemini cable and Drive I/O connector combination that do not tighten down, the Applications Department can send out replacement jackscrews (P/N 51-018062-01) for you to replace in the cable assembly in the field. (Applications Engineering # 800-358-9068)
Note - the FAQ does not apply to the GC-50 or GC-SDA prototyping accessories.
glh Feb 2013