A Clean "Swipe"

Yellow arrow points to black line on pad.

In our recent post on making feeler gauges, we learned that newer gauges can leave a black line on a pad.  If you didn't have a chance to read that post, you can find it at http://www.flutebuilder.com/2013/06/gauging-situation.html.

So, what is the remedy for pads with these unsightly lines?  Would they need to be replaced?  Well, luckily, no!  The line is just a cosmetic issue, and it can be removed with some light cleaning solution.  We revisited flute finisher Lindsey McChord when she was cleaning this line from a pad.  She basically cuts a square piece of cloth and adds some of the cleaning solution to the cloth.  She then places the cloth between the pad and tone hole.  She presses the key down lightly and pulls the cloth out.  She mentioned that it's important to press very lightly, because too much pressure could rip the pad as the cloth is pulled out from the closed key.  As the cloth is pulled out, the cleaning solution cleans the pad (removing the black line) and the top of the tone hole as well.

This particular step of cleaning the pad is used to remedy sticky pads as well.  In the case of a sticky pad, the pad could be sticking due to some accumulation of unwanted particles on the pad, on the tone hole, or on both.  In the flute finishing process, pad cleaning takes place at two different times.  First, the pads are cleaned when the flute is sent over for initial testing.  After testing, there may be adjustments that are made -- and with every adjustment, the finisher checks the pads with the feeler gauge.  So, after all final adjustments are made, and the flute is ready to be shipped, the pads are cleaned once again.  This will assure that the flute is delivered in pristine mechanical and cosmetic condition -- without any black lines!

Getting ready to cut a small square of cloth.

Cleaning solution

Cloth between pad and tone hole, pressing key lightly.

Cloth is pulled out.

Really cleaned that pad!

Wooden Flute Tone Holes -- and More

If you've looked closely at the tone holes on a wooden flute, you may have noticed that they look a bit different from tone holes on metal flutes.  At Powell, metal flutes have either drawn or soldered tone holes, but those choices are not possible with a wooden flute body.  After all, with wood, you wouldn't have the option to solder something onto the body or "pull" the hole up from the body.  No, wood is definitely not as flexible as metal.  So, how exactly are the tone holes formed on the wooden flute?  Are there other differences in how the holes are covered by the keys?

The answer is rather simple, actually.  It's all about subtracting material and sculpting the wood.  With a wooden flute, the tone hole is cut out of the body in a process that is referred to as "milling." However, after the tone hole is milled, more material around the hole must be removed to allow clearance for the key cup.  Since it is a wooden body, you are actually carving or sculpting the wood to create the convex shape around the tone hole.  The tone hole itself has a flat edge, so the key mechanism functions exactly the same as it does on a metal flute.  The key cups and pads are exactly the same size and shape as those on a metal flute -- and they cover the hole exactly the same way as they would with a metal flute. 

But what about the rest of the body?  Is it the same thickness as metal?  Obviously, no.  A wooden flute body is thicker than a metal flute body.  The wood has to be thicker so it doesn't crack.  However, the inner bore diameter of a wooden flute is exactly the same as the inner bore of a wooden flute.  So, there are some differences with the wooden flute but many more similarities. 

Wooden flute bodies before and after tone holes are cut.

Close-up on the tone holes (notice carved covex shape around hole for key clearance)

Final assembly with keys in place.