The Extra Measure

We stopped by the finishing department this week and noticed a small, flat, spatula-looking tool on one of our finisher's benches.  We hadn't seen this item before, because we visit our finishers at different stages of the finishing process.  So, we just had to find out -- what exactly is this tool?  Well, it is a device that the finishers use to measure the distance between the edge of the key cup and the top of the pad.  Instead of just putting pads in key cups and letting them "fall where they may," this device allows them to measure the distance, which is known as pad "protrusion," so that all the pads are seated with a standard amount of protrusion.

Now, the measure is a standard, and it is a beginning point in the pad seating process.  As we know very well, the finishers spend a great amount of time shimming the pads so that they are not leaking or unevenly seated ("light" or "heavy" in certain areas).  Finishers also work with this measurement tool to make sure that the pad will touch the top of the tone hole evenly.  This is quite challenging since the key itself comes down on the cup at an angle.  If the measurement is correct all around, the pad will touch evenly.  If it is not correct, the front or back of the pad may touch the tone hole too soon.  Once everything is in place and measured, the finishers will take a feeler gauge to the pad and double-check the seating.  The finisher may need to add additional full or partial shims, though.  So, not every pad will remain exactly the same, but the tool certainly helps guide the finishers and creates a standard measure to work with in the process.

Small tool for measuring pad protrusion (directly to the right of the flute).

Red arrow points to even protrusion.  Yellow arrow helps point out that the keys close at an angle.

Uneven protrusion.  Red arrow points to front of pad -- which is too high.  Yellow arrow points to pad protrusion in the back.

Checking pad seating with a feeler gauge.

Side-by-side example: Pad is too high on the top cup, good on the one below it.

Finished footjoint.  Shims may need to be added even after a pad is measured, so pads may not always have the exact same amount of protrusion.

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!

Gauging the Situation

Checking pads with feeler gauge.

We've seen our flute finishers checking pads with a feeler gauge, but we recently stopped by to see finisher Lindsey McChord, and she was in the process of making a new one.  Why?  How?  Well, we will answer those questions in this post.

Lindsey explained that the feeler gauges actually do wear out -- and rather quickly.  That may seem surprising, but it is because they get a LOT of use here at Powell.  They are used in flute finishing, repair, and even testing.  The gauge is a small piece of mylar attached to a very small stick.  Lindsey says that she can tell when it needs to be replaced because there will be "wear" at the tip.  Also, when the gauge becomes worn, it tends to snag when being used.  Lindsey uses about 2 gauges per flute -- one for the body, and one for the footjoint.  She says that the number can vary depending on the situation.  Also, if the finisher is working on a flute that is almost done, using a new gauge is not a good idea, because it can leave a black line on the pads.

Making a new gauge involves a few steps.  First, finishers will cut a large piece of mylar, which will be used to make several gauges.  It's convenient to keep this large sheet at their bench.  Then, a very small strip is cut from the large piece.  It's important to cut in a very straight line so that there are no bumps or snags in the material.  Cutting the correct width is important and takes practice.  If the piece is too wide, you will not be able to feel leaks as easily.  If the piece is too thin, you may pick up small things that may seem like problems, when in actuality, the pad seating is correct.  The small strip is then curled vertically just a bit to thread it through the cap.  It's good to have it extend just a bit past the bottom of the cap because it will get pushed forward as the stick is inserted.  Once the cap is secured onto the stick, you are done!  The gauge is a simple tool yet extremely important in detecting leaks and seating issues with pads.  It is also not too difficult to make new ones, although as is the case with flute finishing, practice makes perfect!

Cutting a strip from the large piece of mylar.

A straight cut is important to avoid bumps or snags.

Width must be accurate.  Here, Lindsey explains the issues with a piece that is too wide.

Getting ready to put the new strip on!

Curling the strip to thread it through the cap.

Strip in cap.

A bit of the strip should extend past the cap -- it gets pushed as stick is inserted.

Done!