The incredible shrinking harp

When my replica of the Queen Mary harp was new, Keith Sanger suggested to me that I should measure it repeatedly over time, to see if and how much it changed shape and size over the years.

The idea is to get some idea of how reliable the measurements we take of the old harps in the museums are, and how much the old harps might have changed shape from when they were new to how we see them now.

I went to Belfast to meet Davy Patton and get the harp on 1st April 2007, and so yesterday was marked in my diary to measure the harp again.

I did not measure it as often as I had originally intended and there were gaps in my spreadsheet. I also gave up on the idea of taking measurements of all the wooden components, because it was obvious to me that the error and ambiguity of hand-measurements was greater than the change over time. But I thought that measuring string lengths was worthwhile and so I have kept doing this. I decided that the numbers were interesting enough to make a chart to show you.

My chart shows the most shrinkage happening in the first day or so after stringing and bringing the harp to tension (the 3rd April 2007 measurements were with the harp unstrung as delivered). I am sorry now that I did not re-measure between 7th May 2007 and 9th August 2015, because there was clearly some movement and shrinkage over that time period, and it would be nice to know when. I took the harp to Natalie Surina in March 2015 to have the inside carved out, and it was pulled apart at that time.

You can see from the chart that the harp has continued to shrink since August 2015. The high treble strings have not changed, but the belly of the soundboard has pulled up (not surprising after being thinned a lot). But the lowest bass strings have also kept shrinking more than the margin of error. I estimate all measurements here +/-1mm.

The next date in my spreadsheet is 1st April 2030. Check back then for an update!

Vermilion

Karen Loomis discovered the presence of mercury in the red pigment on the Queen Mary harp, when she did X-ray fluorescence analysis in 2010. This pretty much confirms that the pigment is vermilion, a mercury sulphide compound.

Karen reported that only the pigment on the curved body of the fish on the forepillar indicated mercury; the pigment on the flat panels of the forepillar contained no mercury. A rendering of the CT-scan data printed in her Galpin Society Journal article (vol LXV, 2012, p.166) shows high-density spots in the crevaces between the interlace of the fish shoulders, and also around the fish eye.

As soon as Karen told me about this I thought of re-painting my replica. Continue reading Vermilion

Restringing the Queen Mary harp

I realised it would be somewhat hypocritical of me to recommend my new Trinity College & Queen Mary harp stringing and tuning schedule, with na comhluighe (the sisters) at middle c, if I didn’t put it onto my replica of the Queen Mary harp.

So, last Sunday’s work was to remove all of the old silver trebles and gold basses, and put on the new brass trebles and silver basses according to the new scheme.

Continue reading Restringing the Queen Mary harp

Quill shim

In Karen Loomis’s PhD thesis (volume 3, p.379-380) she prints two photographs of a shim from tuning pin hole no.23 on the Queen Mary harp. One shows the shim extracted; it is made from a split section of a feather quill.

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This photo shows how pin no.29 was going into the neck far too far, because its hole was too big.

On my replica, pins 29 and 30 have needed shimming for some years now. I had originally tried paper, and subsequently sheet brass, but I was inspired by this discovery, to pull the pins and try quill shims.

Continue reading Quill shim

Opening up the harp

I have been thinking for a few years now about the shape of the inside of my harp, in light of the new information we have from Karen Loomis’s PhD research at the University of Edinburgh.

When I commissioned the harp from Davy Patton in 2006-7, the thing we were most lacking was info about the inside – the shapes of the joints, and the profile and thickness of the soundbox. Basically, we had to make a lot of educated guesses.

Since then, we have the CT-scans and other technical studies of the Queen Mary harp that Karen has been working on, and many of our guesses have turned out to be pleasingly correct, such as our choice of timber – willow for the soundbox, and a bent limb for the pillar – but we were quite wrong in our decisions on how to shape the soundbox interior.

Luckily, we had erred very much on the side of leaving the wood too thick, so last week I took the harp to Natalie Surina, of Ériú Harps in Oughterard, Connemara, for her to cut a lot of wood from inside the soundbox.

Continue reading Opening up the harp

A495/370

Last night one of my gold strings popped. It was the f below na comhluighe, one of the original strings I put on the harp when it was brand new in 2007, half-hard 18 carat gold from Blundells in London.

Seeing as one of the higher gold strings had gone, I have taken the chance to redo the stringing and tuning. I took off the two gold strings above the one that went, and replaced all three with silver (the upper na comhluighe with one of my own dust-strings). And I tuned the harp to a new pitch standard of approximately A495/370.

Continue reading A495/370

Making silver harp strings

I have been making silver harp strings for five years. I buy in stock silver wire and draw it down to the size required, which makes it hard as well as thin.

Today I managed to take wire-making to a whole new level. I took 5 years worth of filings and silver dust, and melted them down into a little ingot which I forged into a rod, and drew down into wire. Starting with a pile of dust I finished with a piece of 0.48mm silver wire, about 32cm long.

Unfortunately there was a flaw in the wire exactly half way along, and of course it snapped there almost as soon as I started threading it into the harp.

Using a thin metal toggle I had just enough to put one half onto the highest string of my Queen Mary harp replica. It came right up to pitch and sounds great.  Here it is, wound round one of the new iron split tuning pins:

I stopped annealing it at about 2mm diameter so I rekon on this being about 75% reduction – or “extra hard”. It was pretty brittle trying to wind the toggle, which I presume is from the minute flaws and inclusions from my casting, compared to the very pure metal that is produced by the big industrial producers we usually source wire from.

Now I need to repeat the process with more scrap, trying to produce a longer and thicker finished wire…

“Like medieval clockwork” – copying the missing Queen Mary harp iron tuning pins.

When I was commissioning my replica of the Queen Mary harp in 2006, I paid attention to the 30th tuning pin, which is obviously a later addition, shorter, made of iron, split end, different drive, and off the main row. This pin is now missing but I made a copy of it based on descriptions and old photos. I made the 29 brass pins with their scores on their shafts copying the museum photo of the 21 pins now in the harp, and for the 8 missing pins I made the same design of brass pins without scores.

If I had been more on the ball back then I would have noticed that those same old photos and descriptions I used for the 30th pins, also show the missing 8 from the main row, and those missing 8 are plain iron not decorated brass, and 5 of them have split ends.

So today’s project was to make 8 handmade iron pins, and install them in the harp. The contrast of the iron and brass pins is subtle but interesting in appearance, reminding me of my initial reaction to the handmade decorated pins: “like medieval clockwork”.

I broke the lowest gold B string taking it off but there was enough spare to rewind the toggle and reuse it. The string had thinned where it went over the pin – presumably a gradual process over seven years since I fitted it in 2007.