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I've seen the thread wrap style, and used clamps, but I was wondering what techniques paople use for an action where most are coming off the moldings. Most verticals these days aren't worth a new set of hammers, and I'm exploring repair options.

Thanks

I've had good success using small-size plastic cable ties. You can glue the felt to the molding with CA then put a cable tie round it and pull it tight. Very quick - much faster than wrapping thread. It bites into the felt and doesn't slip off. Trim the end flush, of course. It can be left on permanently, or just long enough for the CA glue to hold. If you email me I can send you pics.

To get optimal results when doing this you want to be able to put some good tension on the felt, stretching it backwards close to where it was originally. If you don't, you can get a noticable difference on the tone with many of the higher partials muffled out...sort of like a needling job that was over done. Although this may not matter much on a piano not worth the price to change out the hammers in the first place, the tighter you get that felt the better it will blend in with the undamaged hammers around it.

I have a clamping device I made out of a large pair of vice grips. I molded 5 different sized forms to the jaws of it using Polymorph, thermo setting plastic. They generally cover a range of hammer sizes from the bass to mid treble. Hammer must be removed from piano to get enough room for it to clamp. I use a small dab of Gorilla glue under the felt, clamp it shut and after it sets, I drill a vertical hole through the back part and wire it for reinforcement just like the factories often do.

This works well for 1 offs but is slow if you have a bunch of them to do.

Hi Dan - I wrap the occasional set of hammers for about 1/3 the charge as a new set of hammers. Here's what they look like when I'm done:

[img:center]http://[/img]

And here's the wrapping in progress for one hammer:

[img:center]http://[/img]

Whenever I do this I always strongly recommend wrapping every hammer, not just the ones coming loose, otherwise there will most likely be continual problems down the road - a lot like replacing broken bridle straps. Might as well do the whole works while you're at it. Chuck

That looks great Mr. Behm. Like some kind of an ethno-art work.

Hi Bojan - Nice to hear from you. Hope things are going well in your end of the world.

The trick in doing these is to use heavy-duty upholstery thread - not just your typical sewing thread. I glue the molding to the felt, then smear a bit of glue on the outside of the hammer over the thread. I've never had one let go after fixing this way.

Obviously, this is not a repair which would be used on a top-end instrument, but for a little Winter spinet or some such piano, it helps keep the piano up and running without the necessity of a repair the owner can't afford. Chuck

Damn you, Chuck, and your amazing attention to detail!

Phil wins...

Un-waxed dental floss, glue,don't leave home without it. In the shop I use stainless safety wire inserted like Steinway NY or "T" wires from BKB Germany.
Cheers

Yet another foot wraps .
If you need to change old pin for junk piano. Don't make it's. There are "foot wraps method" with cardboard

Really, Phil, that's a bit harsh to damn me for showing how to use a bit of thread. I mean, usually when I get damned by somebody it's for something worthwhile, like when I cut in front of them in traffic - very understandable then (I'd do the same thing myself, in fact!)

Actually, I just have fun wrapping hammers this way - reminds me of when I was a kid. My dad - rest in peace - was a band director and made oboe reeds to bring in some extra income. He paid me the princely sum of 10 cents a reed to do the initial wrapping of the cane to the tube using a winder. I enjoyed doing it and got really good at it.

Dad was really the one that taught me that the "devil's in the detail" - that it's your attention to the small things that make a big difference in whether something appears professional or whether it looks amateurish. I always try to keep that attitude in mind when I'm doing piano repair in general and case refinishing in particular.

Anyway, have a nice day, Phil. Don't fall off your bike! Chuck

Chuck, do you use a special kind of thread for this? Have you thought of using white thread instead of black (blends a bit better with the felt)? Not that it looks like a mish mash job, I'm actually quite impressed with the uniformity of how you do this from note to note.

Hi Emmery - No, I hadn't considered using white thread, but that is a good idea - I'll see if it's available. What I use is a heavy duty upholstery thread. You really have to pull hard to break it, unlike ordinary thread which breaks way too easily.

The only trick to my method of wrapping is to start near the tapered ends of the hammer felt with several windings to hold the thread in place then move outward at an angle to about the middle of the hammer. I then double back towards the starting point, ending at the same point as where I began. At this point a double knot is tied:

[img:center]http://[/img]

With the hammer butt secured in the palm of my right hand (see photo) and one end of the thread pulled tight, I use the excess from the other end of the string to make the initial knot. As I said before, I smear a little Titebond over the sides, let it dry a bit, then put the hammer back in the action. Start to finish, it's about a 4 hour job for the entire set.

As I stated before, this repair (obviously) is not intended for a high quality piano, but for a customer on a budget who just doesn't want more and more hammers coming to pieces, it works great. I've never had a hammer come undone once the repair is made. I know other technicians have other methods which work well also - this is just what I do myself. Chuck

Thank you I just learned something today. I am new to piano technology I love the wrapping of the hammers.

By the way Chuck. I can see that eventually, the thread may get in the way of reshaping, assuming one will reshape to the end of the hammers life given the piano is not worth a new set of hammers. But your example looks like the owner is not doing a lot of piano playing.

You might want to fix the thread title - I at first thought you were looking to repair exploding hammers from ffffff playing!