The Oily Rag - British Saloon Car Club

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Renewal Form If it’s time for you to renew your membership in the BSCCOC, here’s a handy dandy ready to go form for you to fill out! If you don’t want to cut up your Oily Rag, you can use a separate piece of paper. Name _________________________________________________________ Address________________________________________________________ City/Town ______________________________________________________ Province/State and Country ________________________________________ Postal/Zip Code _________________________________________________ Email address __________________________________________________ All renewals should be sent to: Roger Tipple, xxxx xxxxxxx xxx, xxxxxxxxxx, xx xxx xxx Questions? email xxxxxx@xxxxxx.xxx Make cheque payable to BSCCOC Make/Model/Year of your British Vehicle(s)___________________________________________________________ PLEASE CHECK ONE: I wish to receive the Oily Rag newsletter by: _______snail mail ________ .pdf file ********************************************************************************************** BRITISH SALOON CAR CLUB OF CANADA REGALIA Quantity Item Colour Cost Total Baseball Hat (Beige, Black, Blue) $10.00 (Mailing for hats) $7.50 License Plate Surround (2 for $5.00) $3.00 Windshield Sticker $1.50 Fridge Magnet $3.00 Total Name: _________________________________________________________ Address: _________________________________________________________ _________________________________________________________ _________________________________________________________ _________________________________________________________ _________________________________________________________ _________________________________________________________ Tel. No.: _________________________________________________________ Note: Prices include all taxes Prices subject to change without notice xxxxxxxxxxxxxx NEW: Note: For shirt orders please place your order directly with KDC Ventures There is no charge for the club regalia but additional embroidery will cost more The options are; go to their web site at www.logoranger.com or call toll free to 1-888-250-4917, fax toll free 1-888-700-7555 To order Regalia only (not renawals) Make cheque payable to : BSCCoC Send to: Anne Koopman xxxx xxxxxxxxx xxx xxxxx, xxxxxxxxxxxxx, xx xxx xxx Tel. (XXX) XXX-XXXX email: xxxxxx@xxxxxx.xxx
“No Noise Is Good Noise” Part One The vehicle NVH (Noise Vibration & Harshness) engineer has four physical properties available to him to reduce/control noise & vibration within a vehicle. - Vibration or panel damping - Noise barriers - Noise absorption - Active cancellation Over my four or so decades in the industry available materials & manufacturing technologies have changed significantly. To a degree, driven by various factors, they have gone full circle. In the sixties available processes and materials resulted in only fairly lightweight products being available to function as either noise barriers or absorbers. At this time available vibration damping materials were applied by spraying. Whilst noise absorbing materials have remained lightweight noise barrier systems have transitioned from lightweight, through increasingly heavy, moulded, components to today’s dual density, significantly lighter, moulded products. The amount of text required to effectively cover this subject is felt to be too much for a single newsletter edition. Therefore the plan is to serialise into three or four editions. 1. Vibration or panel damping materials. These materials are applied directly to the body sheet metal prior to painting; they are heat cured and bond intimately to the steel. Often, in older vehicles, those applied in sheet form, bridged the swages in the sheet steel resulting in holes in the material. The intention was that the material melted to conform to the actual shape of the steel. Such materials are said to be ‘visco-elastic’ they resist the vibrational behaviour of the vibrating sheet steel, converting what is essentially vertical vibration into horizontal movement within the material. Such shear energy is converted into heat via friction as mineral elements rub together. Damping materials are most effective against truly resonant behaviour that is where the panel is freely resonant & not being forced into vibration by surrounding stiff structure. It is all a question of the available correction force. As stated earlier original damping materials were sprayed onto the vehicle body, generally these materials were manufactured from waste paint products their effect being more about added mass than high performance vibration damping. There are two ways to control a vibrating system, introduce damping or add mass; in those early days it was more likely to be the added mass effect. At Triumph the introduction of the front wheel drive Triumph 1300 lead to a lot of work to obtain a material with increased performance to treat the front wheel housings. Spraying of materials in those days was hit or miss being manually applied. Obviously the ultimate test of the material was in its effect upon the vehicles interior noise & vibration levels (vibration can & does cause noise) However less costly testing was required to test material performance as new iterations were developed. In the UK a British Standard procedure was adopted, BSAU125-1965, which utilised a test bar nominally 24” x 2” x1/4”thick. This was of a specific steel type it having been determined that when supported on knife edges at its nodal points (zero vibration) it resonated at 100Hz when struck a sharp blow. Electronic equipment was used to determine the rate at which the vibration resulting from the blow decayed. Comparison is always made with an untreated bar. For convenience, as most electronic measuring equipment utilised Decibels as a unit of quantity, the results obtained were expressed in dB’s/second. The higher the reading the better the material. Interestingly the NA industry also utilised a thick steel plate to determine damping materials performance, the so called Geiger Plate Method. The plate used was thinner than the UK one, probably 1/8” and much larger in area, probably 18” square. This plate was supported on; I think three sharp points, again at nodal points. Both the UK & US methods tested at around 100Hz, most vehicle damping problems occurring at low frequencies The world industry standard today is the Oberst Methodology developed in Germany. Unlike the UK & US methods Oberst utilises strips of body gauge steel in a fixture. The system relies upon electronic excitation to vibrate the test steel. It is therefore capable of determining performance at a range of frequencies. The test stand can also be installed in a small climatic chamber which allows for the automatic testing over a range of temperatures. As with most materials damping materials change their state with temperature, it is important to determine the full range of performance Materials & application techniques have both evolved significantly. Much lighter weight, high damping efficiency materials have been developed which can be applied as flat die cut sheets or very accurately sprayed with robots thereby meeting the demands of high performance with lightweight. Detailed dynamic analysis of body structures enables us to accurately determine both where & how much material is required to alleviate/cure problems thereby increasing occupant comfort. Adding a stiff layer to the upper surface of the material serves to “constrain” that surface. This focuses all of the energy into the core of the material. Such Constrained Layer Systems may have a simple aluminum layer or a stiff cardboard as the constraining layer. Being less flexible they are more difficult to apply in end use as ideally they require a flat surface, which few vehicles have. We, as end users of the vehicle, can make little use of such visco-elastic materials because of the requirement of intimate contact with the sheet metal. However we can make use of another effect, “inter-face frictional effect”. That is a material laid upon a vibrating panel will resist the movement of the panel to a degree, dependent upon the material & its weight. Thus fibre batts laid onto your cars panels will have a positive effect on vehicle noise. Gluing negates the effect As we will see later in the discussion fibre products have additional beneficial effects. Tony Hughes, aka NVH ONE
Page 1 and 2: The Oily Rag July 2008 Issue 82 And
Page 3 and 4: BRITISH SALOON CAR CLUB OF CANADA 2
Page 5 and 6: A Place of Fame in the Movies - and
Page 7 and 8: Car ‘C’ - RUST - Check the rear
Page 9 and 10: Counties Counters Cambridge... Club
Page 11 and 12: looked like a car show. For those f
Page 13 and 14: Latter in the Metro programme he dr
Page 15 and 16: Amsterdam - well what can I say, it
Page 17 and 18: Mini - 1961 Austin Countryman: 850c
Page 19 and 20: A Mini Marvel by Bob DeShane It was
Page 21 and 22: Raiders of the Lost Wreck Compiled
Page 23 and 24: Sunbeam - 1948 Sunbeam Talbot: need
Page 25 and 26: The Mechanics, Toronto, ON, 416-233
Page 27 and 28: W O L S E L E Y By Norm Kear Anyone
Page 29: The View from Burlington By Tony Fo

The Oily Rag - British Saloon Car Club

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