A handful of nice precision element makers photos I found:
Apollo 14 Docking Ring
Image by jurvetson
Milled from a solid block of titanium, with twelve docking latches, it is a marvel of precision design and style in the era ahead of CAD/CAM.
The Smithsonian believed this was the CM docking ring from Apollo 14 Command Module, and had paperwork to help that. I feel it is the sister unit, a big structural engineering element utilised for ground testing to try to recreate the series of docking failures seasoned early in the Apollo 14 mission with the probe that was brought back (normally the docking probe would be left behind). Hence the Apollo 14 label on the base and description at the Bonhams’ auction:
NASA’s choice to fly Apollo missions employing a lunar orbit rendezvous approach necessary the improvement of a method to join, separate, then rejoin two spacecraft. This system also had to let astronauts to move internally between the Command and Lunar Modules. The flight configuration selected was an effect system consisting of a probe situated at the forward end of the Command Module (CM) and a funnel-kind drogue located at the prime of the Lunar Module (LM). The CM’s probe was mounted to the docking ring, which provided a point of structural integrity for the two docked cars as soon as the probe was removed. Removal of the probe produced a tunnel so the crew could travel between the docked cars. A series of latches about the docking ring locked the cars collectively. The tip of the probe had a set of 3 modest capture latches which had been developed to hold the vehicles with each other lengthy adequate that the bigger docking ring latches could be engaged.
Just right after the Saturn V’s third stage sent Apollo 14 on its planned trajectory toward the moon, Shepard along with astronauts Edgar Mitchell and Stuart Roosa seasoned difficulty docking the CSM to the LM. 5 attempts were created but the docking probe capture latches never engaged to secure the two cars together. This could have scrubbed for the second time in a row a lunar landing mission. With the failure of Apollo 13 due to a Service Module oxygen tank explosion, a scrub of the Apollo 14 lunar landing would most definitely have offered ammunition to these in Congress lobbying for an early termination of the Apollo Plan.
Soon after practically two hours of delays and on the sixth try, with Roosa holding the CSM tight with the LM for many seconds, the latches lastly engaged. The crew then activated the series of larger latches mounted along the docking ring to receive a "hard dock" configuration. Though they had been ultimately docked, Mission Manage and the crew’s concern shifted to the possibility that the program could fail when it was most necessary, the redocking of the LM Ascent Stage following Shepard and Mitchell’s return from the moon. If this happened the crew could be forced into performing a space walk in order to return to the CSM. The lunar rocks and scientific data may well have to be abandoned in the LM pending the precise situations of a possible lunar orbit docking problem. The probe was completely inspected by the crew throughout the coast period to the moon and they sent detailed verbal descriptions plus television pictures to Mission Control. Because the probe now showed standard operation of the capture mechanism, NASA created the selection to proceed with the planned mission.
The redocking while in lunar orbit was fully normal. The docking probe (usually jettisoned with the LM) was returned to earth for inspection and evaluation.
NASA and spacecraft manufacturer North American Rockwell performed an exhaustive series of tests to the docking system. All elements (probe, latches, docking ring) had been tested "in location" with the recovered Apollo 14 CM, then each was removed for a series of combined and person tests. The docking method dilemma was a major reason the docking ring was removed and never ever re-installed into the Apollo 14 CM. Post-flight evaluation of tv, motion image film, accelerometer info, and reaction control system thruster activity indicated that probe-to-drogue get in touch with conditions were as expected for all docking attempts. The probe’s capture latches should have worked on every of the 1st 5 docking attempts. A plunger-variety component in the capture latch failed to reach a forward or locked position most likely due to some kind of foreign debris or contamination. A change in the size of the plunger due to temperature was an added possibility. Internal harm to the capture-latch mechanism was ruled out as the cause because the program functioned correctly in all subsequent operations following the sixth docking try and throughout post flight testing. The debris or contamination most probably became dislodged following the fifth docking try, enabling the system to operate effectively from that point. NASA and Rockwell created the decision to supply a protective cover on the tip of the probe to prevent contamination during future flights.
Throughout the tests, the ring was shipped between a variety of NASA and contractor facilities through a 39 by 39 by 12 inch wood transit case which is integrated with the ring. The ring itself has a series of inspection stamps and ID numbers that study: "MDR 408699, V36-316250-9, 06361-B009522, MR 361588, DEC 9 1968, V36 316250 31, ASSEM, FEB 18 1969, 06361A015194." A separate 6 by 3 inch yellow "Temporary Parts Removal Tag" repeats many of these numbers and has the added hand-written information of: "TPS 112, REM #103, Docking Ring, S/C 110, 2/14/72."
Included are copies of documents listing the NASA artifact number (2243) getting from Command Module (S/C # 110) for the transfer to the National Air and Space Museum (NASM) and deascession papers from NASM.
The Apollo 14 docking ring is the single biggest and heaviest piece of lunar spacecraft structural gear ever to be provided to private hands. The flown CM docking ring, the twin of this one particular, remained with the ascent stage of the Lunar Module Antares when it was jettisoned. Antares was then deliberately crashed into the moon’s surface to simulate a "moonquake."