Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum M & H - WNG Repetition Install Issue

Start with the hammer strike angle. If the hammers are pitched forwards and hitting squarely, then you're stuck with the height. If they are under striking, you'll need to lower the top action to improve the strike and regulation; there will also be an improvement to the tone, especially in the treble.

If you decide to lower the top action be mindful of a slight alteration of the strike point. The strike point will move slightly forwards as you lower the center height and you might need to relocate the action further in, mostly at the treble end. Another option would have been to relocate the top action back but you are already at the front of the cushion.

What is the Key Ratio? Is the jack clearing the knuckle sufficiently or being pushed into the stop felt?

On one action, the top action was so mispositioned that I need to elevate the front by 7 mm and the rear by 4 mm. This rotated the hammers back and caused them to hit the belly rail in the last treble section, so I needed to rehang those. The action regulated perfectly and touch weight returned to an acceptable level.

Thought that I would update those who were helping me sort out this issue.......

I started out by checking the hammer to string relationship and found that the hammers were in fact pitched forward to be square, so lowering the stack wasn't going to be an option.
The good news is that my HCH was actually 2 mm lower (150 mm) than I initially thought. Certainly pays to measure and re-measure and re-measure!

One thing that I didn't mention was that I had hung a set of Ari Isaac's hammers on this piano this past fall. They were considerably heaver than the old set, and I was experiencing heavy down weight (65 - 67 grams), which I was hoping to deal with at the same time.

I ended up moving the whippen rail forward and upward, which brought the spread down to 112.5mm from 114.3 mm, and the HCH-WCH differential down to 84mm from 86mm. This adjustment gave me a good jack to knuckle alignment. The old whippens, which appeared to be the originals, had a flange centre pin to jack centre pin measurement of 100 mm, as opposed to the 99 mm WNG's.

I then moved the capstans forward and moved the heels to mate up. My down weight is now 51 - 54 grams, and the heel-capstan contact point is under the magic line at rest. The heels had to move out to their most forward slot.

I was concerned about the lack of after touch, but once I got to regulating, things came together quite nicely. My dip rides between 10 - 10.2 mm and my blow distance averages around 45.5 mm......and the drop screws started coming up. They are still on the low side, but not as they were.

I'm very happy with the results....the combination of these hammers and this set of repetitions has brought this piano to life...I'm quite excited to start recording, which was what I was hoping for when I bought this then very timid instrument last spring.

My thanks to those that helped me puzzle this out...I've learnt an incredible amount reading through the archives of this forum, including discovering the WNG repetitions and Ari's hammers. I live in a fairly remote location in northern Canada, and one has to pretty much fend for one's self up here.

Next will be sorting out some false beats in the treble section!

I posted this snippet of a test recording of this instrument in another forum yesterday....thought some of you may be interested in hearing where it all landed.

https://soundcloud.com/wayne-kelso/m-h-bb

Wayne, that's a fascinating rebuild story. Could you post some pictures of your newly-worked WNG action, please? I would love to see how that turned out.

Thanks.

Hi Steve,

Happy to post a few pics....


Out with the old....these appeared to be the originals, but I'm not sure.



In addition to having to remove material from the whippen rail for clearance, I also had to grind a few of the brackets.



Hanging the new repetitions....



One of the first issues was that there was inadequate clearance between the hammer tails and the helper spring extensions. H & M advised to remove wood from the tails or lob off the extensions..



I chose the latter......



The capstan alignment was also bad......note the let-off buttons on either side of the bracket. That is where they needed to be prior to fooling with the geometry.



The alignment after moving both the capstans (to improve downweight) and the heels......