Hola bialka:

Dos anotaciones: Sobre los bloques de RL ese diseño del LINK ya no son los mejores, puedes buscar en google "jassaf,coldcopper" son de mi autoria .

Y sobre la eficiencia de los tornillos ACME encontré lo siguiente (en ingles) que difiere del 90%:
wikipedia: Low friction in ball screws yields high mechanical efficiency compared to alternatives. A typical ball screw may be 90 percent efficient, versus 50 percent efficiency of an Acme lead screw of equal size. The higher cost of ball screws may thus be offset by lower power requirements for the same net performance.

Un fabricante de tornillos (ROTON) le da menos eficiencia: Mechanical efficiencies for Acme lead screws range from 20% - 40% depending upon the lead angle, coefficient of friction and nut material. Plastic acme nuts offer approximately 10% - 20% better efficiency than bronze acme nuts because of their lower coefficient of friction when running against steel screws.

Salu2
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