Brian May Red Special Replica Build Part 41: Electronic Components Assembly

Over several years beginning in July 2013, I sought and obtained the same vintage electronic components in new old stock (NOS) condition that are fitted to Brian May’s Red Special, namely a set of six Jeanrenaud DPDT (double pole, double throw) parallel slide switches, several Bulgin/Radio Spares 1/4″ jack sockets and TCC Metalmite CP33N paper-in-oil (PIO) capacitors.

I bought 100 Bourns PDB181-GTR02-254A2 audio (logarithmic) taper potentiometers in September 2014 for my 3/4 scale ‘1975’ Brian May Red Special project, individually tested them with a Peak Atlas LCR45 meter and matched them into pairs with a tight tolerance band (1 to 2 kΩ) and sourced the same military specification silver plated barb cone lock PTFE insulated terminal posts from Aerco Ltd Nigel used on the original guitar. French electronics enthusiast and Deacy amp expert Manuel Angelini of kindly supplied the Jeanrenaud switches and replica brown cotton wire sleeving. I describe in parts 8 through 12 how I designed and made the switch frame and potentiometer/capacitor plate from 3/64″ (1.2 mm) thick aluminium sheet.

I wished to make an authentic replica and derive some personal satisfaction from knowing that the guitar will be right ‘under the hood’. Therefore, to do proper justice to all these components, I asked electronics guru Nigel Knight of Knight Audio Technologies to wire them up for me in a facsimile of Brian May’s Red Special guitar. He agreed and carried out the work in December 2017 to his usual exemplary standard as you can see from the attached pictures. I neglected to advise him how I wanted the jack socket wired up to fit the rebate I designed to replicate the original so I will need to move the unsleeved wire onto the top lug of the barrel.

I obtained a selection of vintage Bulgin/Radio Spares jack sockets and a selection of TCC Metalmite CP33N capacitors. Nigel selected a cosmetically clean one, cut the ends off, removed the inner material, inserted a modern Vishay MKT1813 polyester capacitor which measured very similar to the original Red Special in 2013 and closed up the ends to make a pastiche in the same manner as Gibson’s replica historic spec bumblebee capacitors.

Nigel fitted a pair of potentiometers that I measured at 237 kΩ at 20°C; I understand that the ones fitted to Brian May’s original Red Special were at the higher end of the original nominal 220 kΩ tolerance which corresponds to the lower end of the tolerance of these modern nominally 250 kΩ Bourns items. Nigel also supplied the stainless steel potentiometer extenders which he used to sell as part of a kit including matched Bourns potentiometers.

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Part 42: Making a Veneer Scoring Tool
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Part 40: Neck Assembly Preparation