<HTML> <HEAD> <TITLE>Re: [CAUT] M & H model 50</TITLE> </HEAD> <BODY> Aaron= ,     I had bobbling hammers on a Yamaha P22 which only h= appened with the pedal down.  It turned out to be the damper pedal adju= sting wing nut on the trap lever.   When the pedal was down, the t= he dampers could be moved a slight amount by the key.   In very li= ght playing a pianist felt resistance when the spoons hit the damper levers = and that would effectively be the bottom of key travel, consequently bobblin= g hammers.  Regulating it so no movement of dampers could be seen with = pedal held down solved it. -Mike Jorgensen On 2/1/06 12:55 PM, "Vincent Mrykalo" <v.mrykalo@utah.edu> = wrote: <BLOCKQUOTE>Aaron, A thicker but(t) felt will do it for you. On Jan 30, 2006, at 5:58 PM, Aaron Bousel wrote: <BLOCKQUOTE> Hi all,  I sent this about a week ago and got no response, so I thought I'd tr= y again.  Thanks to all who have responded to this. UMass is on winter break un= til a week from Monday and after that I'll have a chance to get back to that= piano (private customer). In response to what I've read so far:  I will of course recheck the regulation, but I don't think that's the= issue. The bobbling happens on a very soft blow when, I suspect, the key do= esn't even go all the way down, so more key dip won't help. I'll check the p= rofile of the butt "leather" to see if a thicker butt felt will al= low better escapement without allowing the jack to skip out too easily.  To go bac! k to why eturn springs as a solution: On a very soft, inco= mplete, blow the hammer is thrown at the string just as the jack hits let-of= f. The hammer then rebounds from the string but since the key has not been f= ully depressed when the hammer rebounds from the string (as someone said, it= could be .005" short of complete travel and that could make the differ= ence) it hits the jack and rebounds off of it. If there is no resistance in = the pinning, and the hammer springs are weak, it will just bounce off the ja= ck, back onto the string, back onto the jack, back onto the string, until it= runs out of energy.  There was one part of my question no one answered. That was about goo= d quality flange bushing cloth. I haven't had to buy any for quite a while s= o I was wondering about a good source. Also, since we had the discussion abo= ut glues; does anyone use anything but hot hide glue for rebushing flanges?<= BR>  And just a bit off topic: My email program (Eudora) monitors incoming= mail for ! questiona nguage, and alerts me by marking such incoming mail wi= th one or more chili pepper icons in my inbox. Several of the posts on this = topic arrived with "chilis" and it took me a while to figure that = the program didn't like all this talk of "butts".  I'm also looking forward to checking out Don's info on the sticker to= ngue position.  (Butts and tongues--what is this list coming to?)  Aaron       <BLOCKQUOTE> <BLOCKQUOTE>There is a Mason & Hamlin upright model 50 (vintage= 1975) I service and at the last tuning the owner was complaining about bobb= ling hammers. The hammer pinning is very loose. I played around with the not= e that was bothering her the most and through a combination of repinning and= strengthening the hammer return spring was able to all but eliminate the pr= oblem. The piano is in good regulation. Here's the issue: The action is real= ly poorly made. 1975 was not e! xactly th n repinning the one I did, I could= see that the flange bushing cloth was poor quality. It would be wonderful t= o replace the whole action, but that's not going to happen. Does anyone know= if it's possible to get replacement hammer flanges? These flanges are diffe= rent from the generic ones sold by piano supply houses. If that's not possib= le, I have to go with rebushing what's there. Any recommendations on a good = source of flange bushing cloth? I know M&H are making these again. Anyon= e know if the action design is the same?  thanks,  Aaron   ------------------------------------------  Aaron Bousel  Registered Piano Technician, Piano Technicians Guild   abousel@comcast.net  (413) 253-3846 (voice & fax) </BLOCKQUOTE>     ----------------! --------- on Bousel  Registered Piano Technician, Piano Technicians Guild   abousel@comcast.net  (413) 253-3846 (voice & fax)       ------------------------------------------  Aaron Bousel   abousel@comcast.net  (413) 253-3544 (voice)  (413) 253-3846 (voice & fax) </BLOCKQUOTE></BLOCKQUOTE> </BLOCKQUOTE> </BODY> </HTML>