I am restoring a Deckel GK2 (older version of the GK21) that I have had for several years but have not used much. Originally it would have had a single speed 1750 rpm motor with max spindle speed of 9500 rpm. A prior owner had replaced the motor with a 3500rpm motor (therefore max speed of 19000 rpm). I am thinking of installing a new motor with VFD control to give me up to 20,000 rpm. The GK21 has a two-speed motor and was designed for 20,000 rpm. The spindles look identical. Although the GK21 manual states 20,000 rpm, it also refers to a "finish milling spindle". I don't see any other spindles on the market. The one sold by Franz Singer looks like mine and has the same pulley diameter (57mm) as mine.
Question #1: Are there separate high-speed spindles for the GK2 / GK21 machines or does the terminology in the GK21 manual refer to the cutter/ machining operation?
Question #2: Is anyone else out there running the standard GK2 spindle at 20,000 rpm?
Question #1: Are there separate high-speed spindles for the GK2 / GK21 machines or does the terminology in the GK21 manual refer to the cutter/ machining operation?
Question #2: Is anyone else out there running the standard GK2 spindle at 20,000 rpm?