>To: pianotech@ptg.org >From: Roger Jolly <baldyam@sk.sympatico.ca> >Subject: Re: V-Pro discussion > >. How is the density different? >>Richard, if they are both cast iron how can one be more dense? >> >>Ed Tomlinson >> >Hi Ed, > The V process is NOT true grey cast iron, quite a quantity of addatives are put into the mix to facilitate the high speed cooling. I also was at the plant for 10 days this spring, and asked specifically about the mix, the reply was, it's a company secret. >The differences in ductility are significant. The sand cast area where the CF3 - S4 -S6 and one vertical model, (not availiable in the US ) had the usual 10% scrap failure rate that you would find at the Kelly foundry. >Yamaha has a marketing story problem with this issue. At the plant when closely questioned, they admitted that the sand pour was the superior product but too expensive when applying their tight engineering tolerences. >Consistency of plates has been a continuous problem within the industry for over 100yrs. the V process over came many of the problems. In a production system it is the lesser of two evils. >Because of the consistencies of V process, it helps the rest of the piano assembly to becomes more consistent. >Yamaha's quality consistency is definitely one of the best, the service support to consumers and techs is an industry model. >Regards roger > Roger Jolly Baldwin Yamaha Piano Centre Saskatoon and Regina Saskatchewan, Canada. 306-665-0213 Fax 652-0505
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