There are two forms of tone hole manufacture, namely ‘Drawn’ and ‘Soldered’ tone holes.  The former is found on all student instruments, mid range instruments and some hand made instruments (e.g. Jack Moore).  The latter is used almost exclusively in hand made flutes.

‘Drawn’ holes are created by a tool which pulls the main body tubing up in a cylinder at right angles.  This is then trimmed and then the ‘sharp edge’ is rolled back on itself to create the top of the tone hole, upon which the key pad will create the air seal for that note.

Soldered tone holes are actually produced from a separate tube of material.  The maker cuts the tube into rings and then shapes one side to fit the curve of the body tubing and makes the other side flat.  The flute maker then cuts holes in the main body tube and solders this ‘ring’ to the tube.

The accepted advantages of soldered over drawn holes are that the soldered tone holes don’t cause thinning of the body tubing, are flatter on top and, therefore, make a better seal for padding.  In practice it is difficult to say whether these advantages really have enough effect to base a purchasing decision on them.