Ron N. and all, > >I'm still waiting for an apology, following my comprehensive reply to >>the company, on this and many other matters in late 1996. Werner >>Husmann are you there? > >Yes, but are you expecting one? An unlikely prospect. > > Interestingly, we have found that the >>optimum drill size, when drilling double flange epoxy fitted pin >>blocks, will be larger than for conventionally assembled pianos. We >>believe this is due to the fitted flanges preventing pin block >>expansion as the pins are driven into the pin block. Where we might >>use a drill size which is 92-94% of the tuning pin diameter for a >>standard pin block, the double flange epoxy fitted blocks typically >>require a drill size of at least 96%. >> >>Ron O > >These numbers would put you in the range appropriate for Delignit. Is that >what you're using? No Ron N, I am not too enthusiastic about Delignit. I realise there are folks out there who speak highly of it, but I just don't care for it. I don't see why we need to smash up the fibres of good wood, only to glue it all back together again. It sort of ends up like the thin lamination Baldwin blocks - with a little too much glue I suspect. We're using planks made from 3 mm thick laminations of solid maple. >Interesting observation, but there is always a price to >pay in confining something made of wood. It strikes me that if the epoxy >bedded double flange installation allows a larger drill size, then the pin >torque levels should necessarily change more from dry to humid seasons than >in a single flange installation, for the same reason that the holes can be >initially bigger with the double flange setup. It's not that you can use a bigger drill size, you actually have to, to prevent the plank from feeling like concrete to tune. We haven't noticed any significant seasonal torque variations to date. While I understand what you're saying about the confining nature of the double flange, it should help to prevent the plank from growing with seasonal changes to upset the unison tuning. At least we won't have the problems associated with poorly fitted planks so common in the single flange fraternity. Makes you wonder why some manufactures waste the metal required to pour the flange in the first place. In many cases, they certainly don't seem to be eager to get the pin block anywhere near it. >I would expect more wood >crush from high humidity with the double flange, and correspondingly lower >torque readings in dry seasons than the single flange installation. >Probably shorter block life too, as a result. Have you noticed anything >along these lines, or have you just gotten into this with the new pianos? I have to tell you that we've only been doing it for three pianos. But we also envelope seal the pin block to smooth out climate transients, and the bushes are glued into the plate to prevent them from turning and bell-mouthing the plank when a string is replaced. While I can see where you're coming from with regard to possible lower summer torque figures, I don't expect it to be a problem. The tuning stability of these pianos so far is proving to be very much superior to anything we've ever put together before. However, the individual-block-system back scale is contributing to stability also. The individual blocks allow for uniform down bearing for each unison group. If a continuous strip is used for bearing adjustment, there will tend to be more down bearing for the right hand shorter back length and less for the left hand longer back length. This has a detrimental effect on tuning stability. Ron O -- Overs Pianos Sydney Australia ________________________ Web site: http://www.overspianos.com.au Email: mailto:ron@overspianos.com.au ________________________
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