Anatomy of a Balrog

Mouse over the picture to see a short description of each part of the Balrog. Click on a part for more information. If neither of those things work because you’re using an ancient or crippled web browser, just scroll down the page.

plinth
600 lb machined granite block, approximately 30″ x 30″ x 8″ with an 8″ diameter hole lined with a 1″ stainless steel tube in center-back, was probably a base for a machine of some kind or an optical device
vibration mounts
four large cast iron and rubber motor-mount type bushings (not shown)
stand
100 lb stand on castor wheels made of 1/4″ steel plate (not shown)
note
the plinth, vibration mounts, stand and castor wheels are a single manufactured unit
shelving
MDF bottom and middle shelves with modeling clay and dynamat damping, fitted plywood top shelf (not shown)
sub plinth
8″ diameter 1″ thick aluminum CNC machined sub-plinth bolted to stainless steel liner in 8″ hole (partly visible under the front of the platter)
platter
VPI HW Jr 1″ thick acrylic platter with a 4 lb lead plate epoxied to underside of platter
bearing
VPI HW Jr bearing with Delrin sleeve bearings and a steel thrust plate with a piece of Teflon on top (not visible)
record clamp
two piece acrylic and Delrin VPI clamp
motor housing
lead shot filled plywood box with height, tilt, and offset/tension adjustments
motor
12VDC Maxon model 110191
power
12V 7Ah sealed lead-acid battery (not shown)
pulley
brass pulley from diyaudio group buy
motor controller
Mark Kelly’s DC motor controller
drive belt
spliced mylar tape
tonearm
Rega Moth RB300
tonearm mods
removed VTF spring, rewired with Cardas 33g wire, steel end stub and steel counterweight damped with lead tape
tonearm damping paddle
buss wire hammered into a paddle on one end, paddle bent to damp in horizontal and vertical planes, friction-fit to the tonearm end stub
tonearm damping pot
damping pot filled with oil (see this vinylengine post or image)
VTA adjuster
VPI dual cylinder type for RB300 with grub screws (not visible)
height measurement
12″ digital height gauge (not shown)
armboard
1/2″ aluminum plate
dust cover
permanent, hinged 3/8″ and 1/8″ plywood with constrained layer damping and foam edge seals, painted white inside to reflect light onto turntable
dust cover mount
plywood, piano hinge
dust cover seal
plywood
cartridge
Shelter 901 and metal protector
viewing aid
white paper cardstock reflects light and provides a high contrast background to the stylus when cleaning it
interconnects
Cardas something-or-other bulk cable hard-wired to tonearm leads in the arm pillar (not visible)
cable shielding
3′ long 1″ diameter spiral steel conduit around interconnects
conduit mount
wood, conduit clamp, screws
hour meter
Honeywell LCD hourmeter module controlled by a micro-switch in the tonearm rest (see this screenshot of long gone webpage with the design)
leveling system
2.5 ton car floor jack, carpenter’s levels, shims under wheels (not shown)

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