This is a build toy based on the Holborn 6100, a rather unique ecosystem of mainframes, computers and terminals.  

It's not an exact reproduction, but it includes most of the visual highlights.

Parts

There are 11 main parts, these can be broken down to main computer, screen and keyboard:

Main computer (6100)

• body-base
• PSU
• PCB
• subpcb1
• subpcb2

Keyboard:

• base-keyboard-cover
• keyboard

Screen:

• screen-fascia
• screen-main-left
• screen-main-right
• screen-connector

For the 6140 drive:

• drive-cage
• drive-cage-back
• drive (x2)

For the 6500 you can print:

• 6500-keyboard
• 6500-keyboard-top
• 6500-keyboard-bottom
• 6500-drive-cage
• 6500-drive-body (x2)
• 6500-base
• 6500-body-top

You will also need the files for the screen and all the internal parts (PSU, PCB, subpcb1, subpcb2)

I've also included the Autodesk Fusion export if you want to edit it.

The only real tip for printing is make sure everything is as flat as it can be and use a high infill because bits have to snap together.

Happy building