| Description | Date | Identifier | |
| Letter to J.W. Roberts Ltd regarding the treatment of a car body with asbestos for soundproofing. | 27th Feb 1933 | Box 138 \ 1 scan0064 | |
| Letter from J.W. Roberts Ltd. regarding a demonstration of their asbestos spray equipment and the treatment of an experimental body. | 2nd Mar 1933 | Box 138 \ 1 scan0065 | |
| Invitation to a demonstration for a process of spraying 'Limpet' asbestos fibre onto a car body. | 2nd Mar 1933 | Box 138 \ 1 scan0066 | |
| Demonstration and trial of the 'Limpet Process' on car bodies. | 3rd Mar 1933 | Box 138 \ 1 scan0067 | |
| Scheduling of Limpet treatment for a black coupe. | 6th Mar 1933 | Box 138 \ 1 scan0068 | |
| Confirming attendance at a demonstration concerning Limpet Asbestos on vehicle 104-MY. | 6th Mar 1933 | Box 138 \ 1 scan0069 | |
| Confirming attendance at a demonstration for Limpet Asbestos at Barker's Works. | 7th Mar 1933 | Box 138 \ 1 scan0070 | |
| Suggesting weighing a car before and after the application of 'Limpet' Asbestos to determine the added weight. | 13th Mar 1933 | Box 138 \ 1 scan0071 | |
| Letter from an asbestos manufacturer discussing the use of sprayed asbestos to reduce sound vibration ('booming') in car body panels. | 13th Mar 1933 | Box 138 \ 1 scan0072 | |
| Letter from J. W. Roberts Ltd. suggesting a method to stiffen a panel by raising the pitch and using spray and batons. | 13th Mar 1933 | Box 138 \ 1 scan0073 | |
| Reporting the 21 lbs. weight increase on chassis 104-MY due to the application of sprayed 'Limpet' asbestos. | 14th Mar 1933 | Box 138 \ 1 scan0074 | |
| The arrangement for spraying a vehicle interior with 'Limpet' asbestos. | 24th Apr 1933 | Box 138 \ 1 scan0075 | |
| Calculation of the effect of Dural connecting rods on the crankshaft critical speed for a Bentley. | 25th Oct 1933 | Box 138 \ 1 scan0076 | |
| Requesting tests on high-speed roughness for a six-cylinder engine by fitting balance weights. | 14th Nov 1933 | Box 138 \ 1 scan0077 | |
| Misunderstandings of 100% balance in four-bearing crankshafts. | 21th Nov 1933 | Box 138 \ 1 scan0078 | |
| List of balance calculations for centre and end units. | 21th Nov 1933 | Box 138 \ 1 scan0079 | |
| Blueprint of an engine crankshaft with multiple views and dimensional annotations. | 4th Dec 1933 | Box 138 \ 1 scan0080 | |
| Modification and testing of Dural connecting rods for a crankshaft with shorter crankpins. | 4th Dec 1933 | Box 138 \ 1 scan0081 | |
| 'CORTEX' anti-vibration material samples received from the Atmo Rubber & Chemical Co. | 6th Dec 1933 | Box 138 \ 1 scan0082 | |
| The performance and testing of a new Bentley crankshaft damper and spring drive. | 13th Dec 1933 | Box 138 \ 1 scan0083 | |
| Testing different spring and damper settings to reduce oscillation and rattle. | 13th Dec 1933 | Box 138 \ 1 scan0084 | |
| Test report on spring drive damping, critical oscillation, and gear rattle. | 13th Dec 1933 | Box 138 \ 1 scan0085 | |
| Crankpin lubrication methods for car and aero engines. | 15th Jan 1934 | Box 138 \ 1 scan0086 | |
| Considerations for engine component lubrication and design modifications. | 15th Jan 1934 | Box 138 \ 1 scan0087 | |
| Describing an instrument for measuring and comparing noise levels in car bodies. | 3rd May 1934 | Box 138 \ 1 scan0088 | |
| New portable noise measuring apparatus from the Standard Telephones & Cables Ltd. | 1st Mar 1934 | Box 138 \ 1 scan0089 | |
| Arranging a demonstration of a portable acoustic meter to measure car body noise. | 7th May 1934 | Box 138 \ 1 scan0090 | |
| Experiments conducted with a Standard Telephone Co. Acoustic Meter to measure noise from various sources. | 14th May 1934 | Box 138 \ 1 scan0091 | |
| Loan of an instrument for measuring noise in motorcar bodies. | 14th May 1934 | Box 138 \ 1 scan0092 | |
| Different materials and methods for sound damping and heat insulation in car bodies. | 18th May 1934 | Box 138 \ 1 scan0093 | |
| Page discussing soundproofing treatments for airliners used by Imperial Airways and Luft-Hansa Co. | 18th May 1934 | Box 138 \ 1 scan0094 | |
| Tests to eliminate excessive headlamp vibration on Bentley vehicles. | 25th May 1934 | Box 138 \ 1 scan0095 | |
| Modifications to lamp pillar fittings to reduce vibration and 'whipping' on various car models. | 25th May 1934 | Box 138 \ 1 scan0096 | |
| Tests to eliminate excessive headlamp vibration on specific Bentley models. | 25th May 1934 | Box 138 \ 1 scan0097 | |
| Tests to stiffen lamp fittings by adding a cross member and stays, comparing results on different chassis. | 25th May 1934 | Box 138 \ 1 scan0098 | |
| Properties and potential applications of Kautex, an anti-vibration and insulation jointing material. | 25th May 1934 | Box 138 \ 1 scan0099 | |
| Letter from Standard Telephones & Cables Ltd. confirming the delivery and price of a Noise Meter. | 28th May 1934 | Box 138 \ 1 scan0100 | |
| Customer complaints about Bentley headlamp vibration, its cause, and potential solutions. | 31th May 1934 | Box 138 \ 1 scan0101 | |
| Tests using an acoustic noise meter to measure noise intensity in works areas and motor cars. | 15th Jun 1934 | Box 138 \ 1 scan0102 | |
| Report comparing vehicle noise levels and assessing the usefulness of the measurement instrument. | 15th Jun 1934 | Box 138 \ 1 scan0103 | |
| Graph of acoustic noise meter readings comparing Bentley and Terraplane cars with various ambient noise levels. | 16th Jun 1934 | Box 138 \ 1 scan0104 | |
| Internal memorandum requesting copies of a report about an acoustic meter for a noise analysis. | 18th Jun 1934 | Box 138 \ 1 scan0105 | |
| Acoustic Noise Meter, confirming the dispatch of extra copies of a previous memo. | 20th Jun 1934 | Box 138 \ 1 scan0106 | |
| Explaining the principles of noise measurement, the decibel unit, and its relation to sound intensity. | 3rd Jul 1934 | Box 138 \ 1 scan0107 | |
| Decibel calculations for sound intensity and car noise analysis. | 15th Jun 1934 | Box 138 \ 1 scan0108 | |
| Acoustic noise meter readings taken in various locations at the works and inside a Bentley and an Essex Terraplane Six. | 15th Jun 1934 | Box 138 \ 1 scan0109 | |
| Report comparing vehicle noise levels for a Bentley and a Terraplane, and evaluating the noise measurement instrument used. | 15th Jun 1934 | Box 138 \ 1 scan0110 | |
| Graph of acoustic noise meter readings comparing a Bentley 16.B.IV and a Terraplane Six at various speeds. | 25th Jun 1934 | Box 138 \ 1 scan0111 | |
| Acoustic noise meter tests conducted in various locations at the works and in two motor cars. | 15th Jun 1934 | Box 138 \ 1 scan0112 | |
| Comparison of noise levels between a Bentley and a Terraplane, with an assessment on the usefulness of the measuring instrument. | 15th Jun 1934 | Box 138 \ 1 scan0113 | |
| Graph comparing acoustic noise meter readings for a Bentley 1B IV and a Terraplane Six against speed, with reference noise levels for various locations. | 26th Jun 1934 | Box 138 \ 1 scan0114 | |
| The limitations of an Acoustic Meter for measuring car noises, particularly low-frequency vibrations. | 1st Aug 1934 | Box 138 \ 1 scan0115 | |
| Table of noise level (db) test results for a 25 HP Barker Standardised Enclosed Limousine under various conditions. | 21th Feb 1935 | Box 138 \ 1 scan0116 | |
| Floorboard and dashboard insulation tests on a Bentley car to reduce engine noise and boom. | 21th Feb 1935 | Box 138 \ 1 scan0117 | |
| Request to borrow a car to inspect recent alterations made to the floorboard and dashboard insulation. | 22th Feb 1935 | Box 138 \ 1 scan0118 | |
| Analysis of floorboard and dashboard insulation results from a Bentley 1 for use on the Spectre model. | 23th Feb 1935 | Box 138 \ 1 scan0119 | |
| Difficulties of fitting floorboard and dashboard insulation to a specific car and proposing to use a standard Bentley for the test instead. | 25th Feb 1935 | Box 138 \ 1 scan0120 | |
| The availability of an experimental car for floorboard and dashboard insulation tests. | 27th Feb 1935 | Box 138 \ 1 scan0121 | |
| Agreed-upon methods and materials for vehicle noise insulation. | 27th Feb 1935 | Box 138 \ 1 scan0122 | |
| Specifications for lining and noise insulation for various car body parts, including the boot and scuttle for a Spectre model. | 27th Feb 1935 | Box 138 \ 1 scan0123 | |
| Tests on a Park Ward Bentley body to investigate and resolve sources of wind noise. | 28th Feb 1936 | Box 138 \ 1 scan0124 | |
| Tests to reduce noise from front door edges, gaps, and hinges at various speeds. | 28th Feb 1935 | Box 138 \ 1 scan0125 | |
| Wind noise reduction tests for front ventilating windows at speeds of 50 mph and upwards. | 28th Feb 1935 | Box 138 \ 1 scan0126 | |
| Noise insulation proposals for the No. 5 Spectre and their potential application to other chassis. | 28th Feb 1935 | Box 138 \ 1 scan0127 | |
| Three further points for the noise insulation of Spectre 3 bodies. | 6th Mar 1935 | Box 138 \ 1 scan0128 | |
| Wind noise tests for a Park Ward Bentley body, detailing sealing issues with the roof and doors. | 7th Mar 1935 | Box 138 \ 1 scan0129 | |
| Technical note discussing the design and noise considerations for front ventilating windows on Spectre models. | 7th Mar 1935 | Box 138 \ 1 scan0130 | |
| Request for the manufacture of one dozen lengthened petrol taps and unions for the noise insulation of Bentley Trials cars. | 11th Mar 1935 | Box 138 \ 1 scan0131 | |
| Suggestions and tests for curing wind noises on a Park Ward Body Bentley, identifying the sun roof as a major source. | 12th Mar 1935 | Box 138 \ 1 scan0132 | |
| Test report on fixing severe wind noise from a Spectre II's sun roof, with recommendations for other models. | 18th Mar 1935 | Box 138 \ 1 scan0133 | |
| Confirming arrangements for coachbuilder Barkers to apply a newly developed insulation scheme to the 99-SK Trials Continental chassis. | 15th Mar 1935 | Box 138 \ 1 scan0134 | |
| Arrangement and execution of noise insulation jobs on several vehicles. | 16th Mar 1935 | Box 138 \ 1 scan0135 | |
| Experiments and methods for noise insulation in Bentley cars using felt. | 14th Mar 1935 | Box 138 \ 1 scan0136 | |
| List of specifications for insulating and lining various parts of a car's interior to reduce noise. | 14th Mar 1935 | Box 138 \ 1 scan0137 | |
| Use of a Barker-bodied Phantom for a noise insulation job and commending Wyman's report. | 16th Mar 1935 | Box 138 \ 1 scan0138 | |
| Arrangements for noise insulation on two cars (GLG-5 and GAE-19) and requesting parts for the dashboards. | 20th Mar 1935 | Box 138 \ 1 scan0139 | |
| Specifications for noise insulation on the 3rd Spectre model. | 20th Mar 1935 | Box 138 \ 1 scan0140 | |
| Proposal for noise insulation features for the 3rd Spectre 3 S.I. (32EX) car. | 18th Mar 1935 | Box 138 \ 1 scan0141 | |
| Specifications for car body components, focusing on flooring, roofing, and noise/draught prevention. | 18th Mar 1935 | Box 138 \ 1 scan0142 | |
| Noise insulation trials on the 3rd Spectre, focusing on the effectiveness of a material named 'Silento'. | 22th Mar 1935 | Box 138 \ 1 scan0143 | |
| Use of 'Silento' as a waterproof noise insulation material for the 3rd Spectre. | 23th Mar 1935 | Box 138 \ 1 scan0144 | |
| The implementation of a body isolation scheme as a standard feature on three car models. | 25th Mar 1935 | Box 138 \ 1 scan0145 | |
| Use of Bestobell Asbestos Blanket and other materials for noise insulation, focusing on water absorption issues. | 26th Mar 1935 | Box 138 \ 1 scan0146 | |
| The noise and heat insulating properties of asbestos and cork for vehicle body and dash lining. | 26th Mar 1935 | Box 138 \ 1 scan0147 | |
| Request to cost a job for the 'Isolation of Body Scheme' and to check the prices being charged by coachbuilders. | 27th Mar 1935 | Box 138 \ 1 scan0148 | |
| Standardisation of design modifications for body noise isolation. | 28th Mar 1935 | Box 138 \ 1 scan0149 | |
| The cost of a one-off body isolation scheme for a standardised Bentley Saloon. | 29th Mar 1935 | Box 138 \ 1 scan0150 | |
| Letter from Vol-Crepe Limited regarding making and sending light samples for testing and requesting confirmation of material weight. | 29th Mar 1935 | Box 138 \ 1 scan0151 | |
| Letter to Vol-Crepe Limited confirming the weight of 1/2 inch felt material. | 1st Apr 1935 | Box 138 \ 1 scan0152 | |
| Arranging a visit to Park Ward's to inspect a noise insulation scheme and experimental car body. | 1st Apr 1935 | Box 138 \ 1 scan0153 | |
| Arranging a meeting at Park Ward to test drive some cars. | 2nd Apr 1935 | Box 138 \ 1 scan0154 | |
| Design modifications for noise isolation of the car body and expressing nervousness about smaller coachbuilders. | 2nd Apr 1935 | Box 138 \ 1 scan0155 | |
| Official order be placed with The British Goodrich Rubber Co. Ltd. for a supply of rubber. | 9th Apr 1935 | Box 138 \ 1 scan0156 | |
| Letter from coachbuilder Park Ward regarding the prohibitive cost of Balsam-Wool insulation from supplier Gliksten. | 9th Apr 1935 | Box 138 \ 1 scan0157 | |
| Letter from Gliksten Doors Ltd to Park Ward & Co Ltd discussing insulating materials for motor cars. | 5th Apr 1935 | Box 138 \ 1 scan0158 | |
| Letter from Gliksten Doors Limited providing a price list for passenger car insulation material. | 10th Apr 1935 | Box 138 \ 1 scan0159 | |
| Letter from Vol-Crepe Limited regarding the dispatch of Brown Vola-Felt material samples for testing. | 10th Apr 1935 | Box 138 \ 1 scan0160 | |
| Requesting an official order be passed to a supplier for one sheet of black fibre. | 11th Apr 1935 | Box 138 \ 1 scan0161 | |
| Noise insulation job and arranging a demonstration of recent experimental work. | 11th Apr 1935 | Box 138 \ 1 scan0162 | |
| Noise insulation methods for car bodies by addressing floorboards, dashboards, and scuttles. | 11th Apr 1935 | Box 138 \ 1 scan0163 | |
| | | | |
