Organs of distinction  JohnPage, Organ Builder



Restoration of the ex-Irvin's Marenghi

Main chest

This is a conventional bar-chest containing 94 channels, three of them large ones for register ventils. There were splits in the table (the chest's top board) So I pegged them where they crossed the bars beneath to prevent wind running from one note to another, and the splits themselves were filled with a sawdust compound. With the pallet-box and calico removed I could see that glue meant for sealing it had lifted in spectacular fashion. Also, five repaired splits ( done in situ a few years ago - keyhole surgery) became clearly visible.

The liberal use of hide glue for sealing the chest had been disastrous. This type of glue, if applied too thickly, shrinks in dry atmosphere, and can come away from the wood. I spent several hours pulling it away from pipe-holes where it had lifted, and then spent several more hours brushing a patent "white" water-based glue (not PVA) into the cracks, and down into each channel. This wasn't wood glue, being designed for fabrics, and it doesn't dry completely, remaining somewhat flexible. It combines with the original hide glue, softening it so the result is a fully-sealed chest which remains sealed when moving in an inevitably changing climate. I call this glue "good-stuff", for obvious reasons.

This work was done with the chest sitting on top of the up-turned case inside the lorry. The idea was to keep it from the worst of the weather. Instead it suffered from the lorry's inadequacies, and more splits appeared after a sunny spell. These had to be treated as above. This was an early warning sign that all was not well with the lorry, and that something needed to be done to prevent further problems later on. I moved the chest to the shed (very "open" without doors), and sent a disclaimer to Graham Atkinson together with an urgent request to get something done about the lorry before more damage was caused. This was ignored, apart from a statement that this lorry had been prepared in a hurry. In fact, he had acquired the organ in August 2002 (unless it really was owned by Ian Cottam after all), and didn't deliver it to me until September 2003 - plenty of time to get a lorry fully prepared and insulated. A further seven months separated the tipping-up of the main case, and its setting upright again. The case could have easily been removed completely and stored in the shed, leaving the lorry free for essential work.

The holes left after mounting screws had been removed from the table were found to be rather worn and were very likely to allow the screws to strip the threads when re-assembling the organ. So all these holes were plugged, following which I lightly planed the entire surface of the table, and the bar side of the chest. The table was then treated with shellac, rubbed in "french polishing" style.

Then came the tedious task of testing the channels for air-tightness. This entailed covering the entire bar side of the chest with masking tape, and similarly covering all pipe holes on the table. Then, uncovering a hole on the each channel in turn, blowing hard into it while noting if the tape covering the neighbouring channels moved. Only then was I satisfied the chest was secure, and all masking tape was removed.

The channels now needed to be covered with calico. This was done using my special "good-stuff". Then it was sealed using a mixture of good-stuff and poster paint. Any further movement of the timber would have to be severe before any splits would occur again in the covering (although the table itself would still be vulnerable). Now the previously cleaned and leathered pallets could be fitted using combination squares for accuracy. These pallets needed to be guided with dress-making pins - always stainless-steel, and angled slightly outwards to prevent the pallets jamming between them.

Attention was then turned to the pallet-box - the wind chamber mounted below the chest, containing the pallets and their springs. This was cleaned out of all loose glue-sealer, which was re-done with shellac. A new gasket surface was applied, and the spring mounting rail installed. In my workshop at home I had made new phosphor-bronze springs, so now they could be fitted to the rail. Tension could be adjusted later.

The chest and pallet box were then re-united. The original face-board was re-used, after cleaning and lining with bedding leather. I lined-in the original stamped notation strip with black ink for ease in recognizing what the various channels do, and re-applied this to the chest just above the face-board.

Now it was ready to be re-installed into the case. However, the case needed a good coat of white paint over the entire inside, after de-greasing it where the Irvins had been over-zealous with the oil can. Once installed, it was connected to the trunking below. All open wind-holes were then blocked with bits of rag so testing on the wind could be done without losing pressure.

One of the home jobs had been the renewing of all the main pushrods (called "stickers" in the trade), fitted with new exhaust pallets. These were carefully set to be of identical length so final adjustment of the puff-board later would be made easier.

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