Damper Guides

Wetting the Old Cloth for Removal

 The damper guides were the next on the agenda.

Damper guides are simply wooden strips which are screwed into the very front of the soundboard.  They have a series of small holes drilled into them which is padded with bushing cloth.  The damper wires (which make up part of the actual damper - I haven't got onto this stage yet in the blog) pass through these holes, which space the dampers correctly to their corresponding strings.

Pulling New Bushing Cloth Through The Holes

Similar to the centre pins which act as joints on a piano, the bushing cloth in these guide rails can sometimes get worn, causing excessive sideways motion of the damper, or can swell due to changes in humidity and grip onto the wire, stopping the movement of the damper.  Both of these faults can cause poor damping.

The old cloth is therefore removed, and new cloth inserted as shown by the pictures opposite.

Glued, Pulled Through, then Trimmed

 As well as this, I also cleaned the wood as best as I could as it looked very grubby, and these guide rails are seen easily once the piano is complete.  On this piano, aesthetics has not been budgeted for, but things like this would look really unsightly to me if I left them how they were when came out the piano

Checking the Wire Passes Correctly

Damper Lift

Damper Lift Before Work

 For those that don't know, the purpose of the Dampers on a piano is to stop the strings ringing once a note has been played.  On a grand, you can see the dampers on the top of the strings when the lid is up. They sit on the strings themselves, a look like a row of shiney black objects, with a white fluffy felt underneath which is in contact to the strings.

These dampers are connected to wires, which run vertically down into the piano itself, to a mechanism called the damper lift.  It is this mechanism I restored next.

This Should Be Swinging!

 The lift comprises of two wooden planks topped with felt, on which are the wooden parts which the dampers' wires are inserted.  I have pictured one to the left on the photo "this should be swinging."  I have given it this dubious title because, as the photo suggests, the joint on these had completely siezed up.  It was a wonder the dampers were working at all!  You can just make out on the photo two little red dots.  These dots are a little tiny metal pin, which is surrounded by red cloth.  These act as the hinges for most joints in a piano action.  There should be a little resistance in them, but nowhere near the amount to make this photo possible!  This is a common problem in piano's where the notes are sticking, or are sluggish.  The red felt has expanded, probably due to changes in humidity, and is gripping onto the pin, causing unwanted friction.  Plus, the pin may have corroded with age.  All the pins in this piano action will be changed.  Doing the math, there are several hundred of these joints in a piano action.  This will take some time!

Punching Out the Old Pin

 First of all, all the old worn out pins will be removed, by pushing them old with a specialist tool.  A new pin size needs to then be selected.  This pin size is quite critical for making sure the action will work properly, and there are several things that the technician needs to consider before selecting the correct size which I will not go into detail here.  However, I will say that the original size of pin needs to be changed, due to wear and tear over the years changing the shape of the hole, and the process of pushing out the old pin.

One Centre Pin

Checking the Friction with a Gauge

Cutting Off the Excess Pin

 Once a pin size is selected, the red felt is reamed out to the precise size needed to accommodate the new pin and generate the perfect amount of friction vs. free play.  (I forgot to take a photo of reaming the felt.)
The pin is then lubricated (some technicians use hair grease for this!  It works surprisingly well actually...) and then is inserted into the part, being very careful not to accidentally push out the red felt.  After this, the friction is tested with a gauge to make sure all is well, and then the protuding end of the pin is snipped off.  The job is complete!

Also on the damper lifters, there are little pieces of green felt on the nose of each.  All this felt was removed and replaced as it had become worn and uneven.  On the damper lift main wooden plank too, the felt had become worn, and wouldnt have eliminated the noise of the damper lifts as they returned back to position fully.  This was replaced by new felt, which was ironed first.

Ironing certain felt is quite useful in piano actions.  Once the piano is assembled, the felt will "bed in" and compress as it takes the weight of the part it is pressing against.  Ironing the felt before applying it to the parts compressses the felt before it goes onto the part and therefore reduces the need for further regulation after the piano is complete..  After that, it was a case of screwing on all the parts back together again and the job was complete!  Looking good, and fully operational damper lift!

Ironing the New Felt

Cutting Felt to Correct Size

Damper Lifters Complete!

 One other note I should make on this post which may be brought to attention in later posts too.  I am using quite poor terminology in a lot of these posts.  For example, the correct name for the "red felt" is bushing cloth, and the pins are called centre pins, etc..  However, to keep things simple for those readers who know less about pianos than others, I am trying to keep things visual rather than technical.  So to my piano tuning buddies reading this, apologies if I refer to something as a "swingy thing" or "red bit"... after all, this is only a blog for interests sake... not as an actual restoration guide!!

One other thing that has made me think of too.  Anyone out there reading this who is thinking "hey, this doesnt seem to bad, I might go and rebuild my dads prized Steinway"  please, for the love of God, DONT!  There are copious amounts of figures and calculations I havent included in the blog, and different bits and bobs which I am neglecting to blog about because they wouldn't be particularly interesting to read about.  All of which are crucial to making a piano work.  Not only that, but every piano, even those made by the same manufacturer, are assembled differently.  This process alters from piano to piano depending on the design and condition of the instrument.

If you restore a piano based on these blog entries YOU WILL WRECK YOUR PIANO!

You have been warned.

New (Red) Felt on the Damper Lift Rail

The Restored Damper Lift

Soundboard Repairs

Without The Iron Frame

 Now that the iron frame has been removed from the piano, I was able to get started on repairing the soundboard and the notorious split.

As the photos show, there was quite a bit of dust and dirt on the board itself (there usually is on grand soundboards, being so exposed) but this was soon removed.

 

Dirt and Water Damage

After Cleaning

View Of Split in Soundboard

Two More Splits in the Bass Bridge

Opening The Split

Shim Glued and Inserted Into Split

Shim Flattened and Old Varnish Removed

Once the soundboard had been cleaned, two more splits showed up in the bass bridge.  It was impossible to see these when the iron frame was in place, as it completely covered them up.

Seeing these splits, I felt even more certain than ever that this was the cause of the buzzing sound which had been the biggest problem with the piano in the first place.

The next step was then to open the splits up more.  This is done so that the chances of the split getting larger by itself are all but eliminated, but also to make the split a uniform depth and width, so that we can insert strips of wedge-shaped wood, called shims, which fill in the split.

There is a special tool especially for this very process.  The shimming tool is basically a sharp spike cut in the same shape as the wooden shims, so that a technician can open the split to the exact shape of the shims which will be inserted.

The shim is then cut to the correct length, the edges shaped to fit the end of the split, and then is glued into place.

Once the glue is dry, the shim (a lot of which is still proud of the soundboard) is planed down level with the soundboard.  Abrasive paper finishes the job and gets the shim to blend in as accurately as possible with the rest of the soundboard.

The whole process of repairing the split inevitably takes off some of the old polish from the soundboard, so whenever a split is repaired, the soundboard needs to be repolished.  As is clear from the photo to the left which shows the shimming tool in action however, the old polish on the soundboard had become crazed with age anyway, so repolishing would have been recommended anyway at this point, even without splits.

The majority of the old polish is removed by scraping it off with a blade shaped for the purpose.  What remains is then removed by various different coursenesses of abrasive paper.  The varnish is removed from the bridges too.  Once flat, any small marks are filled with woodfiller, grain filler is then applied and the board is ready to be sprayed/repolished.

Repolishing the Challen soundboard will have to wait for several weeks as there is already a large Bechstein concert grand in the spray room which needs to be completed before another piano can be moved in.  In the meantime, I decided to begin the action work and key restoration 

Dismantling begins

After a long time getting other projects sorted, the Challen can now be properly started!

Removing the dampers

 I always like this part of the rebuild process.  It seems quite theraputic to be taking a piano apart every so often, rather than the painstaking process of putting everything together just so.

Even so, there is somewhat of an artform, even at this stage of the process!  The photos show several stages which most rebuild projects go through which I work on.

First, the dampers are unscrewed from the damperlift mechanism behind the keyboard, and can then be removed.

Bass String Rubbing

 Next, we measure the bass strings by doing a wax rubbing with a sheet of thick paper.  We also push the paper over the hitch-pins, bridge-pins and agraffes.  This rubbing will then get sent to a bass-string manufacturer who can accurately create a bespoke set of strings specifically calculated for the piano, to give the best possible tone from the instrument in the lower octaves.

Strings Removed

  
Once this is done, the strings can then be removed from the piano.  This is done gradually at first, reducing the tension throughout the piano evenly, so as to avoid putting too much pressure on any part of the frame and soundboard.  The strings are then mostly recycled, apart from one or two of the bass strings, which are sent to the string manufacturer as references in his calculations.

Measuring The String Lengths

As for the treble strings (ie, any strings which are just plain steel, not copper covered,) the length of each these is measured carefully.  We use this measurement to calculate the gauge of wire to replace on each note. (Notes near the top of the piano require a thinner gauge of wire from those further down.)  Thickness of wire is measured to within a small fraction of a millimetre.

Measuring Downbearing

Another thing we do at this stage is measure the downbearing of the piano.  Downbearing is a term which refers to the fact that, when the strings run along the length of the piano, they pass over a bridge (seen in the picture marked Measuring Downbearing, on the left), and this bridge should be slightly higher than the contact points of the string on either side.  On some pianos, this downbearing can disappear and need adjusting.  Running a piece of ordinary string is a good way to test this.  The Challen had no real issues.  Downbearing was still present, and little differences in the balance can be adjusted out later.

Removing the Wrest-Pins

After this, the wrest pins which are used to tune the strings were removed.  Several of these are measured to get their correct diameter, as we will need to put new, slightly larger pins back into the piano when it is restrung.

Following this, the bolts and screws which hold the frame in the piano are taken out.  It is common practice to put the screws in a piece of cardboard, as this helps to relocate them in their correct position later.

Taking the Bolts Out

Finally, the frame can then be lifted out of the piano!  This is another moment I like about the whole procedure; as it means you finally can get access to the soundboard underneath.  I'm hoping this to be the next entry in the blog, and will be able to talk about what we are doing to restore this important part of the piano to great condition.

The Frame Is Strapped Up To The Hoist

Lifting The Frame Out

The Iron Frame

 

Resprayed!

The grand arrived back in the workshop a couple of days ago and is looking wonderful.  I was not able to take many photos, due to the location of the piano and also the fact that the main lid, the fall and several other parts are wrapped up to protect them from damage in a very busy and active workshop environment.  I didn't want to risk any scuffs for the sake of a few photos.  However, you can see the difference in quality below.  Both are of the bass side of the piano.  Both were taken in the same lighting conditions.  Great stuff!  Very pleased with how well the characteristics of the wood have come back out again.

Before

After

Here, too is a photo of the piano as a "whole", excluding its lid, fall, and keys.

The piano is looking fantastic!  Now it is time for the complicated and time-consuming part... the internal parts of the piano.  This is what will take up the vast majority of time and patience.

Unfortunately, we cannot start on it straight away.  Before this piano came in, I had already started to rebuild and restore a Bechstein model V piano, and this needs to be completed before I can turn my concentration onto the Challen.  This Bechstein, along with the fact that I still have a very active tuning round that I need to keep on top of, means that it will be several weeks before I can make this project a priority.  As soon as I can however, expect lots more blog entries to be coming in.  Will be posting a video of the piano being played once completed, hopefully being performed by an up and coming pianist, before it sets back off down to Islington!

The Challen Mini Grand

Recently, I've been asked to restore an old Challen, mid 1930's mini grand piano.

This particular job is a little special, as it has a lot of sentimental value as well as huge professional potential to be used on a regular basis by a dance school in London, so I thought it might be a good idea to keep a diary-style blog to record the rebuild process. 

First time using blogger, so hoping that future posts might be a little better laid out.

A couple of months ago I was contacted by one of my regular customers, who works for a dance school in London, asking if it would be possible to arrange for me to go and check out an old grand.  It had fallen into disrepair in recent times, but if restorable would then be donated to the school by the current owners, who wanted the piano to go to a good home.

Due to a busy schedule and bad traffic on the day of the valuation, I didn't actually manage to get round to see the piano until later in the evening.  By this time, the sun had set and the daylight was slowly dwindling away.  Any other time, this would not have been an issue, but in this particular case, I had to move quite quickly - the piano was in a room which had had all the furniture removed... including the light fittings!

Challen Grand

  My initial glance over the piano was quite promising.  The casework had seen better days, and the internal parts were very dusty, but that was mostly superficial.  I tested the wrestplank in several areas, and it seemed to be stable.  In fact, on playing the piano, it still had a fairly decent tuning in it, for saying that it hadn't been tuned on a regular basis in recent times.  The strings were beginning to rust, however, and a few pins around the centre were definitely not as tight as they should be.  Already, I was thinking it needed restringing.

Damaged Top

 The ivory keys all seemed to be unchipped and reasonably coloured.  The action was in need of serious regulating, but otherwise played and gave the impression that the piano would be a decent instrument once restored.

The biggest cause for concern was a single large split, which ran along the length of the soundboard.  A split soundboard can cause many problems; a loss of tonal quality, buzzing and rattling being common problems. 

The Varnish was faded and crazed

 With the light now nearly completely gone, I'd made my decision to suggest a rebuild, and rang the customer to see what they wanted to do, and was delighted when I got the go-ahead to arrange for a rebuild. 

The last obstacle was for me to get the piano into a workshop suitable for such a task!  I have access to a room in London which is used often for the restoration of pianos, but for a job this extensive, I needed somewhere with all the necessary tools for the work in question.

Enter Mr Phil Taylor, of Phil Taylor Pianos.  His climate controlled, fully equipped workshop in Nottingham is custom built for this type of work, and was my first thought once I realised the extent of the task ahead.

Keys

Within a few weeks, the piano was in its new temporary home in Blidworth, Nottinghamshire, where I took the photos I have included in this blog.  The next step was to get the piano resprayed, which is the focus of the next blog in the series.

Strings showing water-damaged soundboard underneath

Another vuew of the mucky strings and soundboard