Hi Ron, Thanks for the detailed instructions. What do you use the short length of 1/8"x3/4" material for? The cable bracket? Are choke cables still readily available? It's been decades now since I had a car with a manual choke. Bicycle brake cables might substitute, if you came up with a knob, which wouldn't be too hard. What do you use to glue the felt to the aluminum? In any case, this seems less flimsy than what I am imagining the Jansen and Schaff alternatives to be (I've seen one or two over the years, though it's a vague memory). I'll consider the alternative of making an aluminum one. As I've been thinking about this, the Steinway upright I am facing probably has the extra thick pressure bar. Maybe a rod that swings won't work because it can't clear the pressure bar. I'll have to look at the piano. The guy just emailed me this morning, to set up a tuning and, by the way, could I install a practice rail. I will temporize, tell him I need to have a look-see first. Fred On Nov 5, 2009, at 9:56 AM, Ron Nossaman wrote: > Fred Sturm wrote: >> A customer has asked me to install a practice rail (muffler >> felt). I haven't done this retrofit before. I see Jansen has one. >> Are there others? Any advice, comments? > > The easiest way I've found is this. Get a 6' length of aluminum bar > stock, about 1/8"x1/2", a short length of about 1/8"x3/4" steel or > aluminum (or a 3/4" length of 1" angle), and an automotive choke > cable. Measure and bend the ends so it will fit into the piano. Trim > the ends as necessary, and drill holes for the pivots. You can drill > a series of spaced holes for the cable wire so you can find the most > workable leverage ratio by trial and error after everything else is > in. The nice thing about aluminum is that you can dogleg it around > the bass overstring offset to keep the felt as close to the string > as possible. Put whatever padding you want on the action brackets. > Install the felt, trim to the right length (depth), and locate the > pivot points with icepicks, or small nails acting as temporaries. > For the pivots, the damper lifter hanger pins (fluted on one end) > driven into the side of the case work great, and the punching won't > fall off the pin and roll under the piano like it does when the pin > is in the muffler rail arms. Adjust the spread of the arms so it > doesn't slop around. Make a bracket for the choke cable, mounted > under the bass end of the keybed. Fit the cable in the bracket and > determine the length of wrap needed. Pull the wire, cut the wrap, > and push the wire back in. The wrap can be held to the case side by > a couple of Dampp-Chaser wire clips, or simply three 1" sheet metal > screws, two on one side, and one in between on the opposite side. > Push the choke knob all the way in, prop the muffler rail up to > clear the hammers, and make a right angle bend in the wire (toward > the treble), a little above the hole where you think you'll want it. > Another right angle bend, about 1/4" past the first, making a "Z", > gives you a connection to the rail. Take the rail out, tip the > treble end up, feed the wire into the appropriate hole in the bass > end, and reinstall the rail. That's it. If the choke cable won't > hold the rail up, kink it gently until it will. > Ron N Regards, Fred Sturm University of New Mexico fssturm at unm.edu
This PTG archive page provided courtesy of Moy Piano Service, LLC