Origin Live Building a turntable almost from scratch - Manual (Page 12)

12
Example D Cantilever struts
Post
Carbon fibre rod
Sub-chassis
Plinth
Example C
Rubber bands 1-10 off
Sub-chassis
Plinth
Example A
Rod
Plinth top plate
Sub-chassis
Spring
Example B
Sub-chassis
Cupped insert
(optional)
Plinth
The sub-chassis design is highly critical for performance. Conceptually the ideal solution is a rigid frame of low resonance
supported at a point half way between the arm base and platter spindle (this point is ultimately the centre of force
between the cartridge and bearing). Both the bearing house and arm base should be rigidly decoupled from the sub-
chassis. To achieve this we suggest an open frame of steel angle bar bolted together with Allen bolts - See below (welding
or gluing does not appear to work well). A sheet of aluminium plate cut with a jig-saw is simpler and can be stiffened by
bolting on steel angle bar. Whatever your final design, it is recommended that you decouple the arm and bearing house
by means of plates bolted separately to the main sub-chassis assembly. A bearing plate is supplied with the kit for this
purpose.
25 mm Angle bar Arm board plate
Bearing house plate
If you are using the spring kit please see “Diagram of support bolts and spring arrangement” in the section describing the
Ultra kit assembly. This shows how the springs are fitted and seat into a sub-chassis.
Main Bearing attachment
The main bearing is attached as shown in diagram below or in a similar manner.
Bearing House
Plinth
De-coupling brass washer
Nut
Bearing plate
Hole 1.5” Dia or larger