Sheet Material
Tech Cork – Tech Cork is a very firm rubberized composite cork made out of real cork that has been crumbled and then made into a sheet with a binder (i.e. glue). It recovers well after compression.
When to Use: Tech Cork has a good slip to it, so it works well on keys that slide against each other. It is excellent for using under adjustment screws. Since Tech Cork is a harder material, it will make more noise, meaning it is too loud to be used for keys that go straight up and down, and shouldn’t be used on parts of the instrument that touch the body. For other applications, Opti-Kork and Solid Tan synthetic cork are great alternative materials to use. Both are a bit softer and have more give, so they can be used anywhere on the flute.
Quiet Black/ Firm Black – This material is the same material we make our brass instrument valve washers out of.
Opti-Kork / Solid Tan – Opti-Kork and Solid Tan synthetic sheets are technically made of the same material (which we make our waterkey, sax neck and tenon corks from). The only difference between the products is their aesthetic look. The appearance of Solid Tan cork is all one color and when you punch/cut the material it has a smooth cut to it. Opti-Kork is designed to have the appearance of natural cork, so it is speckled and if you cut the material, there might be holes that appear on the edges (just like with natural cork material).
When to Use:
Opti-Kork and Solid Tan are a bit softer and have a bit more give than Tech Cork (but they are still firm materials). Because this material is softer, it can be used anywhere on the flute and even where felt is used at times.
They also have the ability to be a bit adjustable in their thickness when heat is applied. For example, once the material has been compressed, if hot air is held next to (not on) the material, the heat allows the material to expand in size up to (but not past) the original specs.
This material is the only cork sheet that comes with an adhesive back option to it. The adhesive back is great for emergency and quick repairs, however, when working on professional instruments and full servicing, you would want to use contact adhesive, in addition to the adhesive backing, for longer lasting support.
Adhesive/Non Adhesive Backing – Sheets without adhesive can be glued up with contact cement. When working with adhesive backed sheets, you can improve the bond by applying contact cement to the part you are “corking”.
