> I'd think it would be just as easy to say that most if not all > plates can easily withstand the pressures of vertical hitches with the > strings "riding high." Maybe someone knows if this was really a design > consideration at Baldwin. Del? Like anything, it depends, and as usual, no one has proposed mindless replacement of standard hitches with vertical without some intelligent consideration behind it - as it's being argued against. This has all been covered before, and is in the archives. First: With the plate and bridge heights accurately set so the strings are in a more reasonable 2-4mm height range on the hitches, or even up to the height of the aliquot the vertical hitch replaced, rather than the 10+ that seems to be assumed, there isn't a huge lot of added torque on the plate. Second: If you rearrange the hitch pattern so they aren't in the original "break here" straight line perforation pattern, you considerably decrease the likelihood of breaking anything. See photos. Third: If you keep the hitches as far from the plate edge as is feasible, you add further safety factor. Fourth: If you have a minimum allowable plate thickness, like, say, 11mm, you won't be installing these things where it's dangerous to do so. Fifth: If you only drill your pilot holes a couple of thousandths of an inch undersized for roll pins, rather than ten, you can drive the pins in easily with a small light hammer rather than mauling the plate with a sledge to install them. Sixth: If you set the string height at 4mm on the pins as you string it, you'll have some positive bearing when you pull the thing up to pitch the first time. You did, after all, determine beforehand where the bridge would end up under bearing load and set the plate height accordingly, right? Remember, you're in (or are) a small rebuilding shop where you're responsible for doing your own thinking, not in a large factory where you're going through the same narrow operation infinitely on autopilot without verification that the prerequisites to your current operation have been met by someone else. So if you pull the soundboard up off the rim, it's safe to blame personal stupidity rather than the vertical hitches. Yes, there is still a chance of plate breakage, just as there is when you restring a piano with no modifications whatsoever. If it's a big concern, don't install vertical hitches. Vertical hitches in the bass alone can improve bass response with a shorter than optimal back scale, and most bass hitch risers are heavy enough to take almost anything you could do to them. Ron N -------------- next part -------------- A non-text attachment was scrubbed... Name: vertical hitches.jpg Type: image/jpeg Size: 72324 bytes Desc: not available Url : https://www.moypiano.com/ptg/pianotech.php/attachments/20080105/767b0806/attachment-0002.jpg -------------- next part -------------- A non-text attachment was scrubbed... Name: original hitches.jpg Type: image/jpeg Size: 73405 bytes Desc: not available Url : https://www.moypiano.com/ptg/pianotech.php/attachments/20080105/767b0806/attachment-0003.jpg
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