Gamet bearings preload

[Dave123]

Does anyone know how you can measure / quantify the amount of preload on a spindle bearing for a Colchester Master 2500?

Upon disassembly there are in place 12 coil springs, which apply the preload to the bearing.

I am assuming this is the correct number of springs? as there are holes drilled for 24 springs, a spring installed in every second hole

I have sent a request for advice to Colchester and Gamet, so far no response.

Dave

 

[Joe Gwinn]

Does anyone know how you can measure / quantify the amount of preload on a spindle bearing for a Colchester Master 2500?

Upon disassembly there are in place 12 coil springs, which apply the preload to the bearing.

I've heard 12 as well, but this one gets from the assembly drawings for the lathe in question.

I am assuming this is the correct number of springs? as there are holes drilled for 24 springs, a spring installed in every second hole

Same assembly may be used for two different things.

Gamet will have had a thick applications manual on how to design spindles, and the preload (in pounds) will be specified (or computed) there. It isn't super critical, but there must be a reasonable preload.

Nor are Gamet bearings magic. The thick application manuals from current makers of spindle bearings will do in a pinch, with adaptions.