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Cutting A Gear On A Sincere Lathe


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On 10/2/2017 at 9:04 AM, vinn3 said:

good show.  indexing and cutting (hobing).  vin

hmmm, it's not really what hobbing is.  A hob has the profile cut in a helix along its body and both the work and cutter rotate.   The rotation is coordinated, ie keyed together, either through a gear train or electronically (encoder and servo).  The above video is form cutting.  For some technical reasons I don't see hobbing would have the same advantages in horology it does in other mechanics

You need a special machine to hob, either a hobbing machine or a universal horizontal mill with the table can be swung over to match the helix angle of the hob.  

 

Edited by measuretwice
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