Feathers, grading

This mode of grading is used on feathers- It is believed by the writer to be used in the dry treatment of mica. The only plant of this kind of any importance is said to use it but details of the means employed cannot be obtained. Ground mica is used in the manufacture of wall papers, lubricants, fancy paints, molded blocks for electrical insulation. About eight sizes of ground mica are made ranging from 10 mesh to bran mica. 

Ten grams 0.1 g of the representative down or feather sample is placed into a 21 plastic jar. One liter of distilled or de-ionized water (grade 3) is added and the jar is closed with a watertight lid. It is then shaken at least 10-15 times by hand to ensure... 

Higher strengths and better workability may be obtained if all material passing the No. 50 sieve is screened out. The more fines, the less aggregate may be blended in with the epoxy resin. Where it is desired to fill shallow spalled areas, a relatively fine sand of uniform grading may be used, particularly, where feather-edging is to be done. 

Calendering Partially crosslinked grades of NBR are usually used. A minor fraction improves surface smoothness and reduces edge feathering, enabling higher... 

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