In this case I used the displacement method, depress the key 6 mm, measure the hammer rise and divide. You can do it the other way too but I find this to be much quicker. You can simply insert a piece of veneer under one key punching to test it, remove some punchings to relevel the key and test. Very fast. A very careful measuring of up and down weights also can be done but I find that it can be difficult to determine exactly when the key begins to move or how fast and to where the hammer should return in order to accurately determine the UW. UW and DW measurements can very easily by a gram or two and that will throw off your R measurements. If you survey an entire action you will see that the calculated R can be all over the place and you inevitably have to take an average. The dip/rise method is more reliable, at least for me, and much faster. To others who have responded about capstan moving I have certainly done that as well but can’t (at this point) see a really good reason to do one over the other. There may, in fact, be reasons why the veneer method is better should the resulting convergence lines by better or should you not wish to change the capstan wippen cushion contact point for whatever reason. Also, the veneer method is easily reversible. In this case the capstan was already positioned pretty far forward onto the wippen cushion such that a 3 or 4 mm move might well have put it onto the wood. I could have covered the entire heel with felt (or moved it I suppose) but this seemed to be a lot faster and put the action almost exactly where I wanted it. Both methods are fine but I’ve done this on several actions now and I’m beginning to prefer it to moving capstans when possible. There are certainly times when a capstan move is preferable either because it creates better lines or when a new wippen has a heel location such that a repositioning of the capstan is necessary. David Love www.davidlovepianos.com From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of Barbara Richmond Sent: Sunday, June 26, 2011 9:05 PM To: pianotech at ptg.org Subject: Re: [pianotech] Touchweight: Re: half punching & figuring FW Thanks, David. So, what I've wondered is, how you calculate the FWs when using the veneer strip. Do you make all your changes to the action--including the veneer strip--regulate and then take the final down and up weights, enter them into the spreadsheet and then do the calculation? Or something else? Thanks, again. Barbara Richmond, RPT near Peoria, IL where a big thunderstorm is on the way and I'll have to unplug the computer soon...... _____ From: "David Love" <davidlovepianos at comcast.net> To: pianotech at ptg.org, "ptg touchweightne" <ptg_touchweightne at egroups.ptg.org> Sent: Sunday, June 26, 2011 9:43:06 PM Subject: [pianotech] Touchweight: Re: half punching & figuring FW Follow up for Barbara Richmond, somewhere near Peoria: Tried uploading these to the new "higher logic" website but alas, no go (still waiting for those Vulcan consultants to arrive apparently). So I'm posting it here on the old list where it's much simpler and works. @&#*#$(&%*$()$. I hope you see it here. I've copied the new website even though I have no idea how it will come through there. Anyway, this is a picture(s) of the veneer method of lowering the action ratio without moving capstans. It works very well and drops the ratio by about .6. I just did this on an 1970's Teflon Steinway L where I was replacing the action. Switched to 17 mm knuckles but still had a 6.0 ratio (hammer displacement method). Doing this dropped it nicely to about 5.4. (6 mm dip moved the hammer 36 mm on the original (6.0) and 32.5 once the veneer was in place (5.41). Thin veneer (it's probably .025" thick) is cut into strips about 1/8" wide and glued in place behind (in this case since I'm lowering the ratio). In this case I replaced the punchings with thinner ones which I prefer and might be required in some cases. Much easier than moving the capstan and it works quite well. Can also be done in place of changing the shank or knuckle where a lower of the ratio is needed but you're not changing parts or only changing hammers and don't want to alter the hammer weight necessarily. Takes a few hours with all the regulation stuff. Perhaps you are already familiar with the method. David Love www.davidlovepianos.com -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20110627/dca9821d/attachment.htm>
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