Selecta Acoustic Gramophone
(No. 10017)
Project Duration: 40 hours
Date: 1927-1929
Dimensions: L: 410mm W:290mm H:60mm
Materials: wood, brass, steel, motor, velvet, chrome, pot metal, embossed textile
Object Description:
The gramophone was manufactured by a smaller company named Selecta Records, which took part in an influx of acoustic gramophone production between the early 1920s and the early 1930s. Due to its pattern and design, this particular model was likely manufactured between 1927 and 1929. The purpose of the acoustic gramophone is to play sounds such as recordings or music for the listener. The piece was a novelty form of entertainment when it was released, and the portable acoustic gramophone gave way to the ability to take music with oneself wherever they desired.
Condition:
Exterior - The object is structurally sound and intact overall. There is a slight lifting of the coated canvas material along the proper-right side of the case. There is evidence of wood-boring pests along the proper-right side of the lid. Approximately 20 small, circular holes can be seen, reaching up to 1 mm in diameter.
Opaque, dry paint flakes that are white in colour are scattered across the surface of the case. They are superficial and have not been absorbed into the coated canvas. Light abrasions are present on portions of the lid, with the upper proper-right of the case having the most damage to the canvas. These abrasions have removed part of the coating from the canvas, exposing the natural textile beneath.
All metal surfaces are slightly tarnished, having lost their lustre due to extended exposure to humidity and oxygen. The hardware on the exterior is somewhat misaligned, precisely the proper-left clasp on the front of the case. In order to close the case, the hinge and clasp have to warp positions slightly. On the lower proper- right corner of the lid, a single screw is missing.
Interior - Intact and stable. The location of where the swivel joint was once placed remains a vibrant blue. One finishing washer is missing from the screw in the upper proper-left of the case. The turntable on the interior is composed of a ferrous metal that has corroded underneath the wrapped navy velvet textile. The velvet has begun to degrade and is thin and delicate near the edges and at the rust exposed locations.
The winding key is intact, though the wooden handle is worn, likely from use. All additional needles present are corroded. On the underside of the interior, the motor appears intact with visible dust and oil residue from previous lubrication in decades past. The motor is unwound and safe to dismantle for cleaning. The tonearm and soundbox are structurally sound; however, the base of the rear swivel joint, which attaches to the case, is composed of pot metal and has degraded over time. Much of the pot metal is heavily fragmented and warped.
Cleaning:
All surfaces were first cleaned using soft bristle brushes and a netted vacuum, including the velvet turntable.
All coated textile on the object was wet cleaned with 50/50 acetone and deionised water using cotton swabs.
The tarnished nickel-plated metal fittings on the interior and exterior were cleaned with white spirit using fine copper wool.
To aid in restoring the functionality of the motor, it was disassembled and cleaned to remove excess, aged lubricant. The motor was first unwound for safety purposes; then, all components were removed from the base and individually cleaned with ethanol using cotton swabs. Once thoroughly cleaned, the motor was reassembled, then the bushings were oiled with 3-in- 1 multipurpose oil (low viscosity mineral oil).
Stabilisation:
Consolidation was completed on multiple surfaces of the object to prevent further degradation. The fraying fibres on the exterior of the case were consolidated using Klucel G concentration 2% w/v in ethanol and a 00 brush.
Once detached, the turntable was cleaned with white spirit using a brass bristle brush. When all corrosion was cleaned and no more came off with the bristle bristle brush, it was consolidated with three layers of tannic acid (2.5% w/v in deionised water) and set to fully dry.
A lining adhesive was created between the velvet and the turntable by creating a film of Japanese tissue impregnated with a 50/50 mixture of Lascaux 303 and 498.
Once dry, the film was placed between the turntable and the velvet. The velvet was heat-set to the turntable using a tacking iron.
Loss Compensation:
In order to create the replicated rear swivel joint, the most significant fragments were reassembled as closely as possible, and all notable dimensions were taken. The screw locations were notated from the panel inside the case. The threaded collar provided the interior dimensions of the rear swivel joint that the deteriorated fragments could not. Using these measurements, the first version of the design was made in Computer Aided Design (CAD) in full first. The piece was then 3-D printed (white polylactic acid (PLA) 3-D filament) at the Institute of Making and test fit in the case. When fitted to the object, the interior diameter was too small and needed to be widened so that the component sat flush with the panel. The original components were measured again, and three notches were also added to the interior to hold the tonearm in an upright, locked position.
The design was adjusted in CAD to accommodate the necessary material and was printed shortly after. Additionally, to accommodate the possibility of a brass component being made by turning on a lathe and machining on a milling machine, the threading of the original threaded collar was measured using a thread gauge. The threading was determined to be a 26 TPI Cycle thread.
The third design of the piece was mostly successful, however, adjustments had to be made to position the needle accurately and adequately hold the base section of the tonearm in place. The tonearm base was reassessed in terms of its functionality, as aspects of its design were deemed integral but not previously recognised as so. In re-evaluating the component and speaking with a gramophone specialist, it was determined that the original design of the rear swivel joint had taller walls to hold the tonearm and a slightly tighter clearance to aid in stability of the tonearm.
A final brass version was turned on a lathe and created to fit the piece.
