Dear Fellow Mouthpiece Refacers,

I'm wondering what approach others have taken when opening up a 
mouthpiece tip - whether you start at the break and work towards the 
tip, or open up the tip first, and then work on the curve moving 
towards the table.

I've been working on a Meyer tenor mouthpiece that had an uneven and 
concave table. After flattening the table, I needed to open up the 
tip. It just seemed natural to start at the break of the facing and 
work towards the tip. But I wondered if this is how others approach 
this.

What if the table was fine, and the facing length was just right, but 
you wanted to open up the tip - how would you approach it?

Thabnks again,
Peter

Below:

Peter Rawlings wrote:

>  Dear Fellow Mouthpiece Refacers,
>
> I'm wondering what approach others have taken when opening up a
> mouthpiece tip - whether you start at the break and work towards the
> tip, or open up the tip first, and then work on the curve moving
> towards the table.

I start back at the "break", and work the whole facing.

> I've been working on a Meyer tenor mouthpiece that had an uneven and
> concave table. After flattening the table, I needed to open up the
> tip. It just seemed natural to start at the break of the facing and
> work towards the tip. But I wondered if this is how others approach
> this.

Yes, but usually you don't want to lengthen the facing.  Flattening the
table will result in shortening the facing, with an abrupt change at the
curve, not quite the smooth tangent that should be there.  So, the break
must be reworked.

> What if the table was fine, and the facing length was just right, but
> you wanted to open up the tip - how would you approach it?

Then I would start my work about 8-10 mm away from the "break" and work
on toward the tip.  The differences in the curve as measured by the
.0015" and .010" feelers, withe various tip openings and a fixed facing
length, that those two smallest feelers will measure the same.  There is
usually about 5 mm difference between the .0015" and .010" measurement.

It is as you move out to the .014" (an extra one supplied in the
Madison/Winslow kit), .024", and larger, that there will be more
difference between tip openings, each feeler measuring a slightly longer
distance from the tip with a larger tip.  And the larger the feeler
(closer to the tip) the more there will be a difference in various tip
openings.

Do this as an experiment...  Draw, on a large sheet of paper turned
sideways, a straight line  near the bottom edge using a ruler, and on
the left side, another line at right angles to that line.

The bottom horizontal line represents the plane of the table of the
mouthpiece, the vertical line the beginning of the facing.

Center on the verticle line, a round object, a can from the pantry, so
that it is centered on the vertical line, and just touching the
horizontal line.  This would correspond to a curve for a wide tip
opening.

Then use a larger can to draw another curve, and a saucer, then a plate.

You will notice the curves, as they come in at at tangent to the
horizontal line, are all touching, for a short distance, they are
inseparable visually.  And the farther from the vertical line, the
greater the separation.

Now, our tip openings are not varying anywhere near this, and we are
making measurements much closer to the vertical line, the break.

Paul