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Association News

Association News EVENING MEETING company had conducted parallel tests using two departments, one utilising manual methods and the other CAD. The result An evening meeting look place at Caxton Hall on the 11th was a saving in costs of 41 % by the use of CAD. March. Commencing promptly at 7 p.m., the proceedings took The Chairman Mr. Wilson thanked the speakers and invited the form of a debate on "Is There an Advantage of Using CAD those in favour of conventional artwork to put their case to the When Applied to PCB Artwork". meeting. Three speakers spoke for the motion, namely: Mr. J. Scarlett, in excellent form as always and in humorous Mr. B. S. Cheek Plessey vein, mentioned that conventional methods of artwork prepara­ Mr. E. Carpanini Contraves tion were unaffected by such things as power cuts! This much Mr. R. A. Merrion I.T.T. had been proved during industry's three-day week. With three speakers against the motion, namely: As far as he was concerned there was no involvement with Mr. J. Scarlett Exacta Circuits expensive computer maintenance. Furthermore, he considered Mr. J. B. Walker Nevin he was most fortunate in having a design team worthy of their Mr. N. Eilbeck Kodak salt, and emphasised the importance of teamwork—a factor often missing in a CAD environment. The Session was ably chaired by Mr. G. C. Wilson. Mr. Scarlett said he was a little sceptical about the savings The case for the motion was opened by Mr. B. S. Cheek who claimed by the advocates of CAD. Experience had shown that it spoke of his company's experience in the use of CAD. Mention is possible to reduce the turn-round time for the preparation of was made of the fact that the saving in time when compared to conventional artwork to fourteen days providing—as stated manual design varied from 30% to 60%, the latter saving being previously—efficient teamwork is prevalent. There is an addi­ evident in the use of American systems. CAD helped con­ tional bonus in so much that good manual designers continue siderably to eliminate problem areas such as track layout and to learn. Another point to be considered is that although it is affected documents. true that CAD affords excellent attention to detail the overall Mr. Cheek highlighted many of the other parameters which mental picture tends to be poor. he considered to be advantageous, such as accuracy, i.e., A major factor against CAD is that its use often results in a registration marks maintained to a very high degree in the more expensive end product, i.e., the pcb brought about by the order of 0.010. mortality rate experienced by board manufacturers in producing Preparation of NC tapes for subsequent drilling operations very narrow conductor widths and unrealistic hole-to-land becomes a relatively simple matter, since the co-ordinates are ratios, causing breakout after drilling. The minimising of costs programmed from the CAD artwork. Mr. Cheek went on to should be the prime function of a design. How many designers mention that recruitment of drafting labour was always con­ programme in totally unrealistic tolerances—virtually un­ sidered to be difficult and he believed that it was of further obtainable for reasons that the materials used are in themselves advantage that the level of skills required for CAD program­ unstable? Whereas a good manual designer would carry this ming was somewhat lower than that required for manual factor uppermost in his mind. preparation, and consequently more readily recruited. Finally, one should consider that with manual design there is One further point to be considered was that of the general greater flexibility whether one be designing for one off or one level of confidence in the end result. thousand off. The next speaker in favour of CAD was Mr. R. A. Merrion The case for manual design continued to be supported by the who supported his views with a series of film slides which served next speaker, Mr. J. B. Walker, who described in detail— to illustrate the various examples of his company's approach to assisted by slides—a possible alternative manual system. His CAD. Many aspects of the planning programme were illus­ company markets a proprietary plan which, in his opinion, when trated, such as a Coding Example showing Code Circuit Diagram implemented offered distinct advantages. The use of an accurate and the use of punch cards. A further slide illustrated the 1-1 grid utilising twenty or so common patterns greatly helps facilities CAD offered— to reduce alignment errors. It is possible to either delete parts Automatic Design of the positive circuit pattern with a sharp instrument, or by Discreet Components using a negative pattern, print out the unwanted parts of the Test Points circuit. User Restrictions The final speaker on behalf of manual design was Mr. N. Tracking Options Eilbeck who gave an interesting talk, again supported by slides, Another slide served to illustrate Programme Capacity, on the merits of the two-colour taping system which, in his showing the maximum peb size at 256 mm x 256 mm; maximum opinion, greatly aided registration in the preparation of manually DIP 84 (14 or 16 pin); maximum connectors—165 and maxi­ prepared double-sided artwork. Mr. Eilbeck covered all the mum nets—256. important parameters of the system such as colour contrast, Many aspects were covered by Mr. Merrion including one film stability, safe lighting, process latitudes. He went on to give very interesting comparison between CAD and manual facilities, a practical demonstration of an eradication technique used for taking a typical peb layout with a density of 55 DIP. modifying film masters. This concluded the case for manual The labour content using conventional methods was in the design, and the chairman Mr. G. C. Wilson invited members of order of ninety hours plus a tape time of twenty-two hours, the audience to question the speakers. adding up to twenty working days. Using CAD the times were Various aspects of both CAD and manual design were claimed to be drastically reduced with: covered in this period of questioning, with each speaker defend­ Labour 20 hours ing his point of view. The Chairman then invited the audience Computer time at 2.5 hours to vote for and against the motion in the customary manner by Drafting machine time at 3 hours a show of hands. The motion was carried with two-thirds of the audience agreeing that CAD can offer advantages when applied which meant that the resultant artwork was turned round in an to pcb artwork. After a vote of thanks the Chairman closed the average time of ten days. meeting. Two additional benefits to those already covered by the Previous speaker were mentioned as cost stability and standard manufacturing information. ANNUAL SYMPOSIUM The third and last speaker on behalf of CAD was Mr. E. The Annual Symposium will take place at Brunei University, Carpanini who endorsed most of the previous speakers remarks Uxbridge, Middlesex, on the 11th June. At the time of going and strengthened the case by drawing attention to such advan­ to press the programme had not yet been finalised but all tages as Digitising with the use of a small computer and flexibility members will be notified individually by the Secretary. Non- of coupling. Various options, he said, were available such as members wishing to attend are requested to contact the Editor down plotters, flat bed plotters, photo plotters and scribing of this Journal for further information. machines. On the cost side, Mr. Carpanini claimed that his http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Circuit World Emerald Publishing

Association News

Circuit World , Volume 1 (3): 1 – Feb 1, 1975

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Publisher
Emerald Publishing
Copyright
Copyright © Emerald Group Publishing Limited
ISSN
0305-6120
DOI
10.1108/eb043521
Publisher site
See Article on Publisher Site

Abstract

EVENING MEETING company had conducted parallel tests using two departments, one utilising manual methods and the other CAD. The result An evening meeting look place at Caxton Hall on the 11th was a saving in costs of 41 % by the use of CAD. March. Commencing promptly at 7 p.m., the proceedings took The Chairman Mr. Wilson thanked the speakers and invited the form of a debate on "Is There an Advantage of Using CAD those in favour of conventional artwork to put their case to the When Applied to PCB Artwork". meeting. Three speakers spoke for the motion, namely: Mr. J. Scarlett, in excellent form as always and in humorous Mr. B. S. Cheek Plessey vein, mentioned that conventional methods of artwork prepara­ Mr. E. Carpanini Contraves tion were unaffected by such things as power cuts! This much Mr. R. A. Merrion I.T.T. had been proved during industry's three-day week. With three speakers against the motion, namely: As far as he was concerned there was no involvement with Mr. J. Scarlett Exacta Circuits expensive computer maintenance. Furthermore, he considered Mr. J. B. Walker Nevin he was most fortunate in having a design team worthy of their Mr. N. Eilbeck Kodak salt, and emphasised the importance of teamwork—a factor often missing in a CAD environment. The Session was ably chaired by Mr. G. C. Wilson. Mr. Scarlett said he was a little sceptical about the savings The case for the motion was opened by Mr. B. S. Cheek who claimed by the advocates of CAD. Experience had shown that it spoke of his company's experience in the use of CAD. Mention is possible to reduce the turn-round time for the preparation of was made of the fact that the saving in time when compared to conventional artwork to fourteen days providing—as stated manual design varied from 30% to 60%, the latter saving being previously—efficient teamwork is prevalent. There is an addi­ evident in the use of American systems. CAD helped con­ tional bonus in so much that good manual designers continue siderably to eliminate problem areas such as track layout and to learn. Another point to be considered is that although it is affected documents. true that CAD affords excellent attention to detail the overall Mr. Cheek highlighted many of the other parameters which mental picture tends to be poor. he considered to be advantageous, such as accuracy, i.e., A major factor against CAD is that its use often results in a registration marks maintained to a very high degree in the more expensive end product, i.e., the pcb brought about by the order of 0.010. mortality rate experienced by board manufacturers in producing Preparation of NC tapes for subsequent drilling operations very narrow conductor widths and unrealistic hole-to-land becomes a relatively simple matter, since the co-ordinates are ratios, causing breakout after drilling. The minimising of costs programmed from the CAD artwork. Mr. Cheek went on to should be the prime function of a design. How many designers mention that recruitment of drafting labour was always con­ programme in totally unrealistic tolerances—virtually un­ sidered to be difficult and he believed that it was of further obtainable for reasons that the materials used are in themselves advantage that the level of skills required for CAD program­ unstable? Whereas a good manual designer would carry this ming was somewhat lower than that required for manual factor uppermost in his mind. preparation, and consequently more readily recruited. Finally, one should consider that with manual design there is One further point to be considered was that of the general greater flexibility whether one be designing for one off or one level of confidence in the end result. thousand off. The next speaker in favour of CAD was Mr. R. A. Merrion The case for manual design continued to be supported by the who supported his views with a series of film slides which served next speaker, Mr. J. B. Walker, who described in detail— to illustrate the various examples of his company's approach to assisted by slides—a possible alternative manual system. His CAD. Many aspects of the planning programme were illus­ company markets a proprietary plan which, in his opinion, when trated, such as a Coding Example showing Code Circuit Diagram implemented offered distinct advantages. The use of an accurate and the use of punch cards. A further slide illustrated the 1-1 grid utilising twenty or so common patterns greatly helps facilities CAD offered— to reduce alignment errors. It is possible to either delete parts Automatic Design of the positive circuit pattern with a sharp instrument, or by Discreet Components using a negative pattern, print out the unwanted parts of the Test Points circuit. User Restrictions The final speaker on behalf of manual design was Mr. N. Tracking Options Eilbeck who gave an interesting talk, again supported by slides, Another slide served to illustrate Programme Capacity, on the merits of the two-colour taping system which, in his showing the maximum peb size at 256 mm x 256 mm; maximum opinion, greatly aided registration in the preparation of manually DIP 84 (14 or 16 pin); maximum connectors—165 and maxi­ prepared double-sided artwork. Mr. Eilbeck covered all the mum nets—256. important parameters of the system such as colour contrast, Many aspects were covered by Mr. Merrion including one film stability, safe lighting, process latitudes. He went on to give very interesting comparison between CAD and manual facilities, a practical demonstration of an eradication technique used for taking a typical peb layout with a density of 55 DIP. modifying film masters. This concluded the case for manual The labour content using conventional methods was in the design, and the chairman Mr. G. C. Wilson invited members of order of ninety hours plus a tape time of twenty-two hours, the audience to question the speakers. adding up to twenty working days. Using CAD the times were Various aspects of both CAD and manual design were claimed to be drastically reduced with: covered in this period of questioning, with each speaker defend­ Labour 20 hours ing his point of view. The Chairman then invited the audience Computer time at 2.5 hours to vote for and against the motion in the customary manner by Drafting machine time at 3 hours a show of hands. The motion was carried with two-thirds of the audience agreeing that CAD can offer advantages when applied which meant that the resultant artwork was turned round in an to pcb artwork. After a vote of thanks the Chairman closed the average time of ten days. meeting. Two additional benefits to those already covered by the Previous speaker were mentioned as cost stability and standard manufacturing information. ANNUAL SYMPOSIUM The third and last speaker on behalf of CAD was Mr. E. The Annual Symposium will take place at Brunei University, Carpanini who endorsed most of the previous speakers remarks Uxbridge, Middlesex, on the 11th June. At the time of going and strengthened the case by drawing attention to such advan­ to press the programme had not yet been finalised but all tages as Digitising with the use of a small computer and flexibility members will be notified individually by the Secretary. Non- of coupling. Various options, he said, were available such as members wishing to attend are requested to contact the Editor down plotters, flat bed plotters, photo plotters and scribing of this Journal for further information. machines. On the cost side, Mr. Carpanini claimed that his

Journal

Circuit WorldEmerald Publishing

Published: Feb 1, 1975

There are no references for this article.