Today is Monday March 3, my target completion date for this instrument. It's not a date I chose arbitrarily. I have a rehearsal for a show on my schedule at 6:00 this evening, and I need to play english horn. I was stressing about it overnight, because I don't see how I'll be able to pad the lower joint and make all the necessary adjustments by that time in order to be able to play it. The weather gods have been good to me, though, and the school that's putting on the show is closed today because of snow, which means tonight's rehearsal is postponed to Thursday. Add to that the fact that work opened late, and I had all morning to work on the lower joint. I corked all the keys, re faced the tone holes again using what I'd learned from the upper joint (they turned out great!) and faced and glued all the pads.
You may recall that cork pads, because they have almost no compression,need a perfectly flat and smooth tone hole surface to interact with. That also means that the pads themselves need to be flat. They come pretty flat from the manufacturer, but I always reface them by sanding with 600 grit sandpaper on a bench anvil in a figure 8 pattern. That ensures a flat and defect-free surface. It also allows you to thin out a pad if it's too thick for a particular key.
Since cork pads come as disks with no relief on the back, it's necessary to bevel the back of the pad. That way you can shift it around in the pad during leveling, and the glue behind it will have somewhere to go. I bevel pads by simply running a razor blade around the back.
Next the pads get glued in to their key cups. The pads should fit neatly in the key cups so they can't shift from side to side, but they shouldn't be tight at all. A pad that's too tight will be difficult to move during leveling, making it nearly impossible to make the minute adjustments necessary to get a perfect level. If a pad is too tight, I glue the back of it to a screw or nail with a flat top, put that in my bench motor, and spin it while sanding a little bit off the sides. They get glued in with George's Glue (pictured), which isn't the only adhesive you can use, but it seems to be the
preferred choice of most techs for installing
cork pads because it's very sticky and thick. A thick glue is better for
allowing very small adjustments, whereas a runny glue would be more
prone to shift around after you've leveled the pad. I check pad level
with a pad slick that's .0005" in thickness, so the pads have to be
level with the tone hole to within that tolerance. With the pads and corks on, it was time to go to work, so I had to stop for a while so I could get paid to fix other people's instruments. It's a pretty great gig, right?
When I resumed later in the day, I started by replacing some broken springs, installing keys, making final adjustments to key fitting, and leveling pads. The leveling actually went pretty smoothly, owing to all the prep work I'd done on the pads and tone holes. By the time I had all the pads in, though, I was pretty wiped out and done for the day, so I called it quits. The lower joint had a few more issues than the upper joint did, especially with those broken springs, so I kept getting sidetracked by little problems. Tomorrow I'll need to take some time out of work and hopefully finish up. And by "hopefully finish up" I mean that I ABSOLUTELY HAVE TO FINISH THIS THING TOMORROW. There's another rehearsal for the show scheduled for tomorrow night at 6:00, so come hell or high water this english horn will be able to produce some kind of sound within in the next 24 hours.
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