12" Schick Armboard Specifications

PLAN View: You draw an arc (305mm) and find where on the arc to drill: verify clearances of the counterweight section as it pivots; clearance within a dust cover during play and/or at least when the arm is parked, dust cover in place.

Height: the max height when the arm is fully raised under the dust cover (my blackbird base needed a 3/8" t spacer to lift it up high enough due to the JVC TT81’s height above the plinth, luckily the top of the gimbal just fits).

BELOW, consider below deck, for any fastening part needed (Acos Lustre GST-801 and Micro Seiki 505 have very heavy large diameter under-weight fasteners) and clearance for any tool that might need to be inserted, what direction does the cable connect, leave clearance for the cable to bend ..... (Technics EPA-BP500 is a special sideways connector that includes a unique ground pin).

Cable Length, you may want some slack so you can lift the arm-board up enough while the cable is still connected at both ends, disconnect it above the plinth without needing to disturb/move/lift the plinth or the other end of the cable. Then you don’t need to fit your hand/arm below for any reason, which effects the clearances/feet/isolator choices.

I just read about Audio Technica AT616 feet which are both adjustable height and isolation type. I like the feet on my friend’s Luxman PD-444.

For me, the failsafe method is to have the blank board made and fitted to the TT.  Then using a gauge of whatever kind that fits over the spindle, measure the distance from the centerline of the spindle to the centerline of where you want a hole drilled in the armboard to accommodate your tonearm. Then remove the armboard with the point located, for example on a piece of masking tape fixed to the mounting board surface before measurement, and send it to the machinist for drilling the proper size hole. It's analogous to what a good body shop does when fitting a panel to a car.