Our definition for the Mechanical Phase is that everything that turns or moves under power now does so. This includes driving the whole machine from our DC power supply.

The nature of this project was that nothing appears to happen on site at Bletchley Park and then suddenly all the previously manufactured sub assemblies are brought together and fitted over a short period of time. This was the case with the Letchworth Enigmas, Vertical and Horizontal shafts etc. These were all fitted and commissioned in less than two weeks during April 2002. It says a great deal about the quality and dedication of the team that virtually no problem  was found during this phase of construction.

We are were now able to demonstrate the following sequence


1 Run the motor up to half speed
2 Engage the clutch which results in all 37 top drum shafts rotating
3 Increase the speed to full
4 Engage the carries and see both the middle 37 drum shafts and the bottom 37 (slow) shafts operate in ‘ripple down’ mode
5 We then simulate a ‘stop’ where the carries are stopped. We cannot at this stage mark the position of the top drums because the relay system was not installed
6 The machine drops to half speed
7 The clutch is disengaged and the top drums locked. At this stage the clutch was disengaged at an arbitrary position. When the Stop-Start unit and relay system was operational the machine stopped back at the same point where the original ‘stop’ was detected



Below is a close up of the front of the machine. The most obvious missing items are the commutators. Also the Start and Stop switches have yet to be fitted at the bottom right of this view

The rear of the machine is the more mechanically interesting part of the machine.

Compare this with the original

Look at rear of machine

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