| Description | Date | Identifier | |
| Letter to Ferodo Ltd. regarding a planned visit to Chapel-en-le-Frith to compare testing methods. | 7th Jan 1924 | Box 26 \ 4 Scan218 | |
| Letter from Ferodo Limited enclosing a diagram about the coefficient of friction for Ferodo Fibre and Ferodo Bonded Asbestos. | 7th Jan 1924 | Box 26 \ 4 Scan219 | |
| Letter from Ferodo Limited confirming a meeting and lunch arrangement. | 10th Jan 1924 | Box 26 \ 4 Scan220 | |
| Letter from Ferodo Ltd. regarding the postponement of a proposed visit. | 11th Jan 1924 | Box 26 \ 4 Scan221 | |
| Brake linings, comparing Halo and Ferodo materials and their performance when hot. | 15th Jan 1924 | Box 26 \ 4 Scan222 | |
| Hand-drawn exploded diagram of a clutch lining testing rig. | 15th Jul 1923 | Box 26 \ 4 Scan223 | |
| The wrapping and non-wrapping action of rigid brake shoes. | 17th Jan 1924 | Box 26 \ 4 Scan224 | |
| The mechanics and torque of wrapping and non-wrapping brake shoes. | 12th Jul 1923 | Box 26 \ 4 Scan225 | |
| The coefficient of friction and servo pressure for front brakes. | 17th Jan 1924 | Box 26 \ 4 Scan226 | |
| Visit to Chapel-en-le-Frith to discuss brake friction materials and squeaking issues. | 17th Jan 1924 | Box 26 \ 4 Scan227 | |
| Page 2 of an experimental report discussing clutch lining wear, testing methods, and friction coefficients. | 17th Jan 1924 | Box 26 \ 4 Scan228 | |
| Obtaining data from a servo brake. | 22th Jan 1924 | Box 26 \ 4 Scan229 | |
| Series of tests on an E.A.C. servo for a brake testing rig. | 1st Jan 1924 | Box 26 \ 4 Scan230 | |
| Tests to demonstrate the effects of speed and heat on brake linings. | 1st Jan 1924 | Box 26 \ 4 Scan231 | |
| Comparing the horsepower absorbed per square inch of lining on the 40/50 rear wheel foot brakes with that of the servo. | 12th Jul 1923 | Box 26 \ 4 Scan232 | |
| Report attributing excessive servo wear to a lack of cooling facilities causing brake linings to roast. | 18th Nov 1924 | Box 26 \ 4 Scan233 | |
| Performance analysis graphs and diagram for an E.A.C. Servo mechanism. | 18th Nov 1924 | Box 26 \ 4 Scan234 | |
| Study on the effect of high temperatures on the wear and mechanical gain factor of a servo mechanism. | 21th Jan 1929 | Box 26 \ 4 Scan235 | |
| The dispatch and examination of two sets of servo brake liners from test cars. | 23th Jan 1924 | Box 26 \ 4 Scan236 | |
| The despatch of two sets of brake liners for examination. | 23th Jan 1924 | Box 26 \ 4 Scan237 | |
| Servo brake testing, comparing cast iron liners with Ferodo material. | 23th Jan 1924 | Box 26 \ 4 Scan238 | |
| Testing E.A.C. servo brake shoes lined with cast iron. | 1st Jan 1924 | Box 26 \ 4 Scan239 | |
| E.A.C. servo performance, comparing Ferodo and cast iron liners. | 26th Jan 1924 | Box 26 \ 4 Scan240 | |
| Comparing brake performance with latest modified leverage versus standard leverages. | 26th Jan 1924 | Box 26 \ 4 Scan241 | |
| Confirmation of a telegram suggesting a test on rear brakes by removing the non-wrapping shoe. | 29th Jan 1924 | Box 26 \ 4 Scan242 | |
| Tests on brake friction, referencing an attached chart from Ferodo. | 2nd Feb 1924 | Box 26 \ 4 Scan243 | |
| Receipt of 16 sample 'HALO' Metallic Brake Shoes for practical testing. | 30th Jan 1924 | Box 26 \ 4 Scan244 | |
| Secret memo discussing the cause of 'brake jaggers' (judder), raising objections to a theory, and suggesting further tests. | 30th Jan 1924 | Box 26 \ 4 Scan245 | |
| Page two of a document discussing the requirements for a damping device. | 2nd Feb 1924 | Box 26 \ 4 Scan246 | |
| Internal memorandum requesting an order for 4 Friction Discs from Messrs. Ferodo Ltd. | 2nd Feb 1924 | Box 26 \ 4 Scan247 | |
| Letter from Ferodo Limited discussing the properties and application of Ferodo Fibre friction material. | 18th Feb 1924 | Box 26 \ 4 Scan248 | |
| Issues and potential improvements for clutch and servo linings. | 19th Feb 1924 | Box 26 \ 4 Scan249 | |
| The co-efficient of static friction of brake shoes. | 19th Feb 1924 | Box 26 \ 4 Scan250 | |
| Brake and servo friction materials and issues with unequal pressure distribution from the equaliser. | 2nd Feb 1924 | Box 26 \ 4 Scan251 | |
| Drawing for an E.A.C. clutch modification, changing the driven disc material from steel to ferodo. | 22th Feb 1924 | Box 26 \ 4 Scan252 | |
| Mr. Royce's suggestions for improving braking by modifying brake shoe design and length. | 27th Feb 1924 | Box 26 \ 4 Scan253 | |
| Continued memo discussing results from designs and semi-flexible steel shoes. | 27th Feb 1924 | Box 26 \ 4 Scan254 | |
| Mechanical gain, friction, and potential issues in a new slow-speed servo for braking schemes. | 27th Feb 1924 | Box 26 \ 4 Scan255 | |
| Continued memo suggesting a test method for tying two plates together using pins underneath the ferodo plates. | 15th Feb 1924 | Box 26 \ 4 Scan256 | |
| Letter to Messrs. Ferodo Ltd. regarding an order for friction discs made from Ferodo Fibre. | 15th Feb 1924 | Box 26 \ 4 Scan257 | |
| Graph showing the average coefficient of friction and temperature rise of Ferodo bonded asbestos lining over time. | 8th May 1925 | Box 26 \ 4 Scan258 | |
| Page with handwritten calculations and an office date stamp. | 8th May 1925 | Box 26 \ 4 Scan259 | |
| Instructing the Drawing Office to change the material for servo disc facings from Ferodo to Halo. | 5th Jun 1924 | Box 26 \ 4 Scan260 | |
| Request for a report on 40/50 Brake Shoe Liners supplied by 'Scandinavia' Belting Ltd. | 25th Jun 1924 | Box 26 \ 4 Scan261 | |
| Letter from the Asbestos Brake Lining Association regarding a centralized clearing house for brake and clutch specifications. | 6th Oct 1924 | Box 26 \ 4 Scan262 | |
| Data request form for brake lining and clutch facing specifications from the Asbestos Brake Lining Association. | 6th Oct 1924 | Box 26 \ 4 Scan263 | |
| Data request form from the Asbestos Brake Lining Association for brake lining and clutch facing specifications. | 21th Oct 1924 | Box 26 \ 4 Scan264 | |
| High scrap rates for Slipper Drive Friction Discs and a proposal to test a new material. | 21th Oct 1924 | Box 26 \ 4 Scan265 | |
| Receiving brake shoe linings made from Brasbestos material for experimental purposes on the 20-HP chassis. | 20th Nov 1924 | Box 26 \ 4 Scan266 | |
| Improved form of brake lining from Creswell of Bradford with a coefficient of friction of .45. | 6th May 1925 | Box 26 \ 4 Scan267 | |
| Internal order request for half a dozen Ferodo Discs to drawing G.52141. | 22th May 1925 | Box 26 \ 4 Scan268 | |
| Letter from British Belting & Asbestos Ltd concerning clutch and brake lining performance data. | 10th Jul 1925 | Box 26 \ 4 Scan269 | |
| Requesting that two other cars being built are fitted with the newly approved 'India' servo parts for testing. | 14th Jul 1925 | Box 26 \ 4 Scan270 | |
| Covering letter forwarding correspondence from John G. Cloke regarding brake blocks used on Sunbeams. | 16th Jul 1925 | Box 26 \ 4 Scan271 | |
| Letter proposing a new 'antithermal' friction material for brake blocks and clutch inserts. | 14th Jul 1925 | Box 26 \ 4 Scan272 | |
| Letter discussing a soft yielding antithermal pad for friction applications. | 8th Jul 1925 | Box 26 \ 4 Scan273 | |
| Proposed response to a J.G. Cloke regarding an unsolicited 'Antithermal Material' sample. | 8th Jul 1925 | Box 26 \ 4 Scan274 | |
| Ferodo Ltd's materials for main clutches and servo clutches. | 21th Sep 1925 | Box 26 \ 4 Scan275 | |
| Drilling difficulties with Ferobestos non-squeaking brake liners supplied by Ferodo Ltd. | 25th Sep 1925 | Box 26 \ 4 Scan276 | |
| Efficiency of servos and the recommended method for measuring it. | 16th Nov 1925 | Box 26 \ 4 Scan277 | |
| Comparison of the coefficient of friction over time for mild steel on cast iron versus 'Halo' asbestos brake lining. | 19th Feb 1926 | Box 26 \ 4 Scan278 | |
| Letter from Ferodo Limited discussing collan oil as a dressing for asbestos brake linings and the causes of brake squealing. | 19th Feb 1926 | Box 26 \ 4 Scan279 | |
| Letter from Ferodo Limited discussing brake lining noise, glazing, and performance comparisons. | 19th Feb 1926 | Box 26 \ 4 Scan280 | |
| Comparison of the coefficient of friction over a 10-minute period for 'Mintex' flexible brake lining versus Cast Iron on Cast Iron. | 21th Jan 1926 | Box 26 \ 4 Scan281 | |
| Letter to Ferodo Ltd. confirming a thorough test on 'Ferobestos' impregnated with oil compounds for its anti-squeaking properties. | 21th Jan 1926 | Box 26 \ 4 Scan282 | |
| The despatch of Ferobestos brake linings to Messrs. Ferodo. | 2nd Feb 1926 | Box 26 \ 4 Scan283 | |
| Letter to Ferodo regarding the testing of 'Ferobestos' brake lining and issues with brake squeaks. | 12th Feb 1926 | Box 26 \ 4 Scan284 | |
| Experiment with 'Perlit' brake shoe material. | 1st Mar 1926 | Box 26 \ 4 Scan285 | |
| Advertisement for 'Fibrent' pure asbestos brake linings, friction linings, super motor jointing and asbestos millboard. | 1st Mar 1926 | Box 26 \ 4 Scan286 | |
| Advertisement and price list for 'Fibrent' asbestos brake linings. | 1st Mar 1926 | Box 26 \ 4 Scan287 | |
| Advertisement for Fibrent asbestos brake lining by British Fibro Asbestos Products, Ltd. | 13th Mar 1926 | Box 26 \ 4 Scan288 | |
| Letter chasing up a promised delivery of brake lining, stated to be free from squeaking tendencies, from Messrs. Ferodo. | 13th Mar 1926 | Box 26 \ 4 Scan289 | |
| Letter from Ferodo Limited concerning a delay in supplying experimental brake linings and a reference to Colan oil. | 16th Mar 1926 | Box 26 \ 4 Scan290 | |
| Letter to Ferodo Ltd. regarding the supply and testing of oil impregnated and bonded asbestos brake linings. | 12th Apr 1926 | Box 26 \ 4 Scan291 | |
| Letter from Ferodo Limited regarding an omission of parts for 20 HP and 40/50 HP cars in a consignment of experimental brake linings. | 15th Apr 1926 | Box 26 \ 4 Scan292 | |
| Experiments with brake linings and lubricants to overcome squeaking front brakes. | 17th Apr 1926 | Box 26 \ 4 Scan293 | |
| Instructing stores to send two clutch plates to Ferodo Ltd. to have friction material die-pressed onto them. | 20th Apr 1926 | Box 26 \ 4 Scan294 | |
| Letter to Ferodo Ltd. regarding the development and testing of clutch plates with moulded friction fabric for 40/50 HP and 20 HP cars. | 20th Apr 1926 | Box 26 \ 4 Scan295 | |
| Letter from Ferodo Limited concerning the materials and production of special clutch discs. | 23th Apr 1926 | Box 26 \ 4 Scan296 | |
| Testing of new Ferodo Bonded Asbestos brake linings for models 11-G-11 and 12-EX. | 27th Apr 1926 | Box 26 \ 4 Scan297 | |
| Letter to Ferodo Ltd. requesting the co-efficient of friction and wearing qualities for newly received anti-squeaking brake linings. | 27th Apr 1926 | Box 26 \ 4 Scan298 | |
| Letter from Ferodo Limited detailing the coefficient of friction and wear characteristics of an experimental brake lining. | 29th Apr 1926 | Box 26 \ 4 Scan299 | |
| Letter to Messrs. Ferodo Ltd. regarding the delivery status of 40/50 HP clutch plates. | 29th Apr 1926 | Box 26 \ 4 Scan300 | |
| Letter from Ferodo Limited regarding a delay in the preparation of experimental clutch plates. | 1st May 1926 | Box 26 \ 4 Scan301 | |
| Decision to replace the 20 HP dynamo pinion brake component with a new die-pressed Ferobestos part. | 7th May 1926 | Box 26 \ 4 Scan302 | |
| Letter to Ferodo Ltd. regarding experiments with anti-squeaking brake lining and clutch plate materials. | 19th May 1926 | Box 26 \ 4 Scan303 | |
| Request to dispatch a 40/50 HP Clutch Plate to Messrs. Ferodo Ltd. | 19th May 1926 | Box 26 \ 4 Scan304 | |
| Letter from Ferodo Limited agreeing to supply brake linings and discussing the manufacturing of a clutch plate. | 25th May 1926 | Box 26 \ 4 Scan305 | |
| Issues with an experimental 12-EX clutch and potential friction materials. | 31th May 1926 | Box 26 \ 4 Scan306 | |
| Letter from Ferodo Limited concerning the forwarding of a 20HP Clutch Disc for testing. | 4th Jun 1926 | Box 26 \ 4 Scan307 | |
| Letter from Ferodo Limited regarding the completion and dispatch of 40/50 HP Clutch Plates. | 4th Jun 1926 | Box 26 \ 4 Scan308 | |
| Order confirmation from Ferodo Limited for steel clutch discs lined with friction material. | 5th Jun 1926 | Box 26 \ 4 Scan309 | |
| Advice note from Ferodo Limited for lined steel discs. | 5th Jun 1926 | Box 26 \ 4 Scan310 | |
| Performance concerns for a new Ferodo brake material related to heat, moisture, and rusting of the brake drums. | 10th Jun 1926 | Box 26 \ 4 Scan311 | |
| Letter to Ferodo Ltd. regarding the testing of oil-impregnated brake and clutch linings. | 16th Jun 1926 | Box 26 \ 4 Scan312 | |
| Proposal from supplier Morgan, Crossley & Co. for their TENOID asbestos brake linings, claimed to be superior to Ferodo. | 9th Nov 1926 | Box 26 \ 4 Scan313 | |
| Technical memorandum discussing the issue of squeaking brakes and potential solutions. | 19th Nov 1926 | Box 26 \ 4 Scan314 | |
| Letter to Morgan, Crossley & Co. Ltd. acknowledging receipt of information on brake linings, which is being returned. | 14th Dec 1926 | Box 26 \ 4 Scan315 | |
| Modifying brake shoes to eliminate squeaks on the 40/50 HP lightened axle. | 15th Dec 1926 | Box 26 \ 4 Scan316 | |
| Ongoing testing of brake components, including duralumin shoes, drum dampers and brake straps. | 15th Dec 1926 | Box 26 \ 4 Scan317 | |
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