Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum What is it with Steinway Agraffes?

It is easy assuming you can use a larger one, if not the same thread than the one used to repair spark plugs...

Never had to do so, probably another method exists.

For over twenty years I replaced 3-4 Steinway agraffes per year without any problems. Then around four years ago, all within a month, I had three in a row that needed to be drilled out. I haven't gotten a call for one since then and at this point don't even know where my agraffe stock is. I'm sure they're somewhere.

One easy way to remove the threaded shank from a plate hole is to employ a reverse direction drill bit in a reversible variable speed drill. Center punch the shank and "thread" the shank up out of the hole. The bit will "bite" into the brass and lock to it.

Easy outs just expand the brass so much that the shank locks into the plate hole threads-so I don't use them. The bit diameter should be just below the shank diameter. I was taught this method by Bill Smith who is a member of my Seattle Chapter of PTG.

What amaze me is that one can buy reverse direction drill bits.
What are they intended for ?

If you have to figure it out....

Fank you, but I don't

They are for drilling left-handed holes, of course!

I thought lefty drill bits were for battery powered drills that are stuck in reverse...

Thanks. I found some. I'm going to try to get a gunsmith to round the chamfer a bit.

Greetings,
I burnish all the interior holes of agraffes. I do this with a piece of bass string which has been rolled between two files to slightly roughen it, then swedged sufficiently enough be larger than the agraffe holes. I clip the string off so that the swedging is right at the end of the piece and then, with a 10 or 12 inch length of this wire chucked in an electric drill, spin this swedged part in the agraffe. I guide the wire in by hand and push it slightly in while I give it a spin. It doesn't take any appreciable amount of material off, but it does smooth the bearing surface of the agraffe. I rarely get a false termination out of them, this way.
Regards,

Olek,
I use a regular twist bit that is the diameter of the existing outer chamfer. You must re-grind the angle on the tip so as to leave the two cutting faces more like a scraper than a screw. This way the bit will not want to thread itself into the soft brass. Machinist's here call it "nubbing" the bit off. You still have the same angle to the profile of the point but remove the "chisel" relief from both faces.

Then I set up my drill press and adjust the stop depth to leave the string contact point in the center at about 1mm or a little less after I chamfer from both sides. I don't measure it I just eyeball it with a magnifying glass, and I do the entire set of agraffes this way. Usually you need a bigger size bit for the singles and bi-chord.

Thank you Ed,

if you had some pics of the modified bit ...

I also (I told you yet) would be very interested to hear a "before / after" and to see the aspect of capos and agraffes after 10 years.

Not that I do not trust you, even for you it would be good to have pics.

I believe that the agraffe I use are relatively well machined, I'll make a few pictures tomorrow, may be they are not in need of that modifictaion.

The trouble with agrafes is the "crack" when there is wear and a kink in them , after 15-20 years. Fine tuning is really not easy then.

About agraffe noises, this is really exceptional, in my experience. Only with really worn out instruments, that need to be repaired anyway.

Best regards

Pianotek in the USA sells them

Once the agraffes are chamfered properly they will provide good service with no end point in sight. The crack you refer to is a sign that the string contact point is now so broad that the string will not move smoothly through the hole because it must be bent anew by the tuning process. At some level it is probably buzzing slightly.

The string holes in agraffes are not correct. I have tried to get Klinke to make me an order of agraffes to my specifications. They will not take the order even if I offer to pay in advance for their minimum order. I assume they think the way they do it is perfect and I should just be happy with that! It is so disrespectful of professionalism. Oh Well!