Pads and adhesives

[moondaddy]

Trying to put pads on an old Conn sterling flute. I think some of the tone holes have a little warpage so it's been tough going. Using a feeler gauge and little arcs of shims. How much can seating a pad with dampening and key clamps make up for not getting it perfect with the shims? Also, not related to screw-in pads, but what are french cement and amber and clear stick shellac made of?
Thanks

[pied_piper]

Pad seating is somewhat dependent upon the type of felt in the pads. Needle felt or pressed felt is denser and much more resistant to taking an impression, if any at all. Woven felt pads are somewhat softer, less dense, and will take an impression. Most manufacturers use woven felt pads on student and some intermediate flutes, because they require less work to get complete coverage. Needle felt pads are usually used on the upper end flutes since more hand assembly and fitting is required. Ferrees Tools has some more info and hints that you may find helpful: http://www.ferreestools.com/pads_flute.htm

So, try dampening the pads and clamping them down until dry. If they are woven felt, they will take an impression. If not, then you'll have to do more shim work, key leveling, or tone hole leveling to get complete coverage.

I don't know the composition of french pad cement, but shellac is obtained from an insect secretion that is harvested from tree bark where the insects nest. Wikipedia has a lot more info: http://en.wikipedia.org/wiki/Shellac

[moondaddy]

Thanks a lot for the links. Are both amber and clear shellacs made from the insect secretions or are either or both synthetic?

[pied_piper]

The Wikipedia entry indicates that the insects diet (the type of tree sap they consume) influences the color (orange or blonde). It also says "Orange shellac is bleached with sodium hypochlorite solution to form white shellac and also is produced in wax-containing and wax-free form."