Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum wurzen felt on bluthner grand.

Hello, i'm setting up a new action on a Bluthner grand, and am thinking about using Renner hammers with wurzen felt, rather than VFG.

Just wondering if anybody tried these hammers on a Bluthner?

They sounded great on the Steinway B i just finished!

Thanks.

I haven’t tried the Wurzen AA’s on a Blüthner yet but plan to next month.

Blüthner hammers are cut differently than other hammers; make sure you get the correct set specifically cut for Blüthner.

The vast majority of Renner hammers are made with felt from Wurzen; this has been the case for some years, as I understand it.

Thanks for the replies.

Yes, i meant to say wieckhart special..i was under the impression that traditionally,Bluthner uses VFG felt? I think it was something Andre oorebeek told me.

Dan, how do you mean?-Bass chamfered,tales shaped etc?-I'm replacing the patent action with a new renner action design and new keyboard,so the boring scale is totally different too.
I always use the hammers designed for Bluthners without any problems, but just curious!

That is the slicing , AND the boring that are totally different from other brands.

I would ask the factory where to find the best heads.

Using standard bored/sliced hammers make a change in tone toward a more "standard" piano, it is also not ideal for backchecks, but you may need to change them.

describe the Bluethner hammers :
They are all bored with zero angle (straight in the molding)

The strings angles is directly followed by the way the hammer set is sliced after pressing.

some shaping on the sides of the wood is also due, but there are some advantages to that shape, perfectly lining tails for instance, and also it is easy to file the hammers gang style.

If the hammers have been well sliced/bored, you will see them lining.

I dont know about felt quality used (they dot say, but say it is done for them), but you may wish to consider using the one they have I rarely have seen hammers that produced as strong rebound before needling and that need not so much voicing.
(the voicing is also not usual, partially due to the excellent quality of the heads)

may be the heads are "soft pressed", anyway no hardness, for the ones I have seen, incredible warm and strong rebound, needing no much pre voicing

I once ordered a set of hammers from the factory, and they were sent directly from Abel.

The patent action is quite unique and works beautifully when setup correctly. Why do you want to replace it with a standard action? In case you may not be aware, Jurgen (Supply) sells all the parts you'd need to do a factory-level restoration, including vellum for the damper underlevers.

Yes they make the heads , the felt is in question, really an excellent felt...

I received mine from the factory. I would suggest to really provide the hammer center and string's plane height section by section, as a "standard" bore is Ok up to 3 mm height inconsistency at the string's level, burt Bluethner may really show some very large distances there (I have seen 225 mm for the plain strings )

at some point a trade of between too tall hammers (above 48-50mm) and too much overcentering (above 3-4 mm) is to be defined.

A new action have no problem with 55mm long hammers until it is heavily played, then the centers really suffer I would avoid that as much as possible.
(I had to change the whole shank and hammer assembly on a less than 10 years old grand - Hoffman made by Petrof) due to the extra long hammer producing too much flex and waving of the Renner shank.

I agree. With the proper parts -- i.e., leathers, felts, hammers, etc. -- these are quite nice actions. They are not the same as the modern, and blandly ubiquitous, Renner style actions, but that is their beauty. Much more suitable to the original piano.

ddf

Thanks everyone, lots of useful info Isaac, thanks for that.

Do Abel do other felts except VFG then?-I always use Abel Bluthner heads, but have often found them to be too bright and hard. Which is the reason i was interested in trying other options..

Yes, i quite like the Bluthner patent actions too, but i work for a company, and so have to do what the customer/manager wants. I just do what i'm told!

Issac, i've found a good compromise with no over centring, and still maintaining good geometry on the magic line. Not sure it would work with a 225 string height though!-Thats high!..This one is around 212-214 on the steels.

Hi Abel uses the same felt than Renner on demand , different Wurzen qualities etc

Overcentering (overblow) is a feature that allow to play FFF without the "electrical shock" under the fingers. it sort of adbsorb some extra hardness on the impact.

Good feature (widely used , Bluethner use 91 92° on the shank so there is some)
That 1° on the shank is a minimum.

Overcentering is also allowing the hammer to impact the strings (slanted>2-3° in high treble) at 90° and that , makes something about the tone crispness, in my experience.

ALso because it allows to have less tall hammers. WHenever possible I like to avoid more than 48 mm (215 is yet enormous, when you will notice 196 mm on most modern grands)

Then, measuring, evaluating and deciding for bore is a 3D job, and all but easy to realize, one may need a top notch gig (I simply leave a tendency, and adjust with the reamer before dry mounting, the models being more important than the rest.

If one look at the backside of a grand hammer set it can be often noticed that there is some bend that side. Only allowing the hammers to line at the strike line level..

I sometime try to reproduce the strike line shape under the shank, at last for the samples, but a good line under the strings (elastic thread) is OK

I am unsure AA is still produced. This have to be verified...

Weickert special possibly is replacing it (with a higher cost too)

I think that at various times, Blüthner has had their hammers made in different ways, just like other piano companies.

The one Bluthner patent action piano I played was one of the most responsive pianos I've ever seen, so I wouldn't change it either, unless there was a very good reason to.

Like i said, i'm just doing what i've been asked to do.

Thanks Isaac.
Are you saying it would be better to shorten the bore and rake the hammers to 92 degrees?
So if my bore is 50mm, you would go for 48mm with a 92 degree rake angle instead?
(And...how do you do the degree symbol!?)

Use MS word doc> insert>symbols. Then cut/ paste and you're done. Here is a whole bunch of them for you…
92⁰ 91 ⁰ 90 ⁰ 89 ⁰ 88⁰ 87 ⁰86 ⁰ on and on…..

° is shift-option-8 on a Macintosh.

it is

º is shift-option-m on my mac. But I have a french keyboard so.....