The Bagpipe Society

G.L.O.P. -- the Great Linseed Oil Project of 2015 (Or Pouring Oil on Troubled Turners)

If procrastination really is the thief of time then I must be a sort of temporal Great Train Robber. It’s not that I have fewer or less interesting good ideas than the next man, but it seems to take me an eternity to actually make them happen. It was thus with the Great Linseed oil Project of 2015. I had known for years that various of my colleagues used impregnation systems to drive oil deep into the wood of their instruments. Julian Goodacre’s website describes how he lovingly uses pressure, vacuum and heat to soak his instruments with linseed oil, and on a visit to Sean Jones’ workshop a few years ago I had seen his vacuum impregnation cylinder looking not unlike the centre console of Dr Who’s Tardis. It was clearly the way to go, and I was going to go there.

Oiling wind instruments serves two main purposes. It can provide a durable and attractive surface finish which will improve with age and re-oiling. More importantly, it seals the bore and improves the tone. All wood has a fibrous texture (very noticeable with maple, for example, less so with box or blackwood) and even the sharpest reamer will not leave a perfect finish inside the bore. The effect of the resulting minute irregularities is to induce turbulence in the air stream and this is perceived acoustically as a sound which is flat in pitch and lacking in higher partials – lacking brilliance and “zing”. Oiling the bore increases the pitch and enlivens the tone. As the oil dries, the effect reduces, but the oiled bore will always sound better than the unoiled, and a judicious application of oil can work wonders on a tired chanter. I have a mental image of the parched wood fibres thirstily sucking up the golden oil, swelling to bursting point and putting their final seal of approval on the maker’s careful work (of course, you can do much the same thing with Superglue, but the poetry, the poetry…).

To get a good external finish, multiple coats are needed. This is time-consuming and can occasionally be tricky if, for example, the oil doesn’t dry as expected. How satisfying then to do the whole thing in one process, immersing the components in oil, applying a vacuum and watching while the wood bubbles and boils as if deep-fried, and the nourishing oil is drawn deep inside.

Slowly, the necessary parts were assembled. A small but efficient vacuum pump came off Ebay, as did tubing and taps. I wanted to be able to see what was happening, but Perspex tube of the right size proved harder to obtain. I make shawms as well as bagpipes, so I wanted something wide enough to take a tenor shawm bell, and deep enough to take the stem. Eventually I found a plastics supplier who could help, and even offered a choice of thicknesses, 3 or 5mm. Ever thrifty, I went for 3mm.

You can see where this is going can’t you?

I decided to use a mixture of boiled linseed oil and pure turpentine. I could have used Danish oil, but I wanted to offset the slightly hi-tech impregnation system with a more traditional recipe. Boiled linseed dries much more quickly than the raw stuff, but is rather sticky and viscous. Pure turps would thin it down nicely and add its delicious aroma to the finished instrument. The tube was large, so several litres of both ingredients were needed. I solvent welded the tube to its base, with silicone to reinforce. At the top, I made a neoprene gasket and fitted an airtight tap. The plan was to wind the vacuum up, then close the tap and leave the whole thing to fizz and bubble away for 20 minutes or so. The first attempt was impressive; a cloud of vapour formed above the oil as the turps began to boil off, and a few seconds later streams of bubbles were pouring off the components and the oil was bubbling up the tube very satisfyingly. I closed the airtight tap and the thing calmed down enough for me to realise that there was a tiny stream of bubbles emerging from the bottom seal; a pinprick leak. But I had shown that it worked, and the treated components were fine. It was a few days before I was ready to run it again, and I laboriously drained it down and re-made the seal. No leak this time, but the mist of solvent appeared again, and the bubbling started. I decided I would try to get the bubbles up almost to the top of the tube before shutting off the tap, and so I was watching closely when, with a report like a cannon going off, the whole bloody thing imploded.

With incredible speed and completeness, the workshop and everything in it was engulfed in a tsunami of linseed oil. A tidal wave of the stuff hit the (low) ceiling while great jagged shards of Perspex ricocheted off the walls and windows. In the silence that followed I realised that, mercifully, I was unhurt but had mysteriously entered a bizarre parallel universe based entirely on linseed oil, an oilyverse. Linseed oil rain dripped down my back. Through the oil-dimmed windows I had a vision of a linseed Niagara with linseed pterodactyls wheeling overhead. Could there be life based entirely on oil? In a flash of oleaginous insight, I understood at last where Nigel Farrage came from. I turned off the vacuum pump and returned to consensual reality.

Clean up - how to? Newspaper, and lots of it. I left the workshop and walked through the house, leaving a trail of oily footprints, to the later annoyance of the formidable Mrs Parr. I trudged down to the corner shop. “Gawd” exclaimed the hoodied youth behind the counter, “what happened to you? And what’s that smell?” I opened my mouth to explain but no words came, so I shut it again before I made a fool of myself. A bigger fool. “How many copies of the Sun have you got?” I asked, when the power of articulate speech returned. “Dunno -I’ll have a look- fifteen” “I’ll take the lot” I said masterfully, proffering oily coins. Back in the workshop, I began to cover everything with Rupert Murdoch’s finest. Everyone knows that newspaper goes clear when oily, but when really soaked in oil the images and print almost vanish, becoming wraith-like and insubstantial. I murmured a silent prayer that the Page 3 girls were better clad now - the image of those nipples, receding into the oilyverse like the grin of the Cheshire Cat, would have been too much for me.

The G.L.O.P. has left its mark, literally and figuratively. An expensive diamond honing plate is probably ruined, coated in a stubborn varnish of dried oil. I recently spent 90 minutes cleaning up a hand plane whose thread had become locked with oily gunge. And the smell still lingers. But the project was a worthwhile one, and I will return to it, with heavier duty Perspex, a pressure gauge and a new awareness of just how deeply Nature abhors a vacuum.