1. #1
    I bought this several years ago to increase the speed on my benchtop mill high enough to use single flute V-bit carbide engraving cutters for marking vernier wheel graduations on a job, when I'd finished the job I put it on a shelf and forgot about it.
    Last year I came across it again and for no really good reason decided to pull the chuck off - it came off but so did the taper it mounted to, scrapping the output shaft! Back on the shelf it went.
    Last week I noticed it again and stripped it to find that the centre shaft was mainly 10mm with a 6mm section for the floating top bearing and a ground "race" in the middle for the speed increaser ball drive to engage.
    Yesterday my latest order of 4 ER11 Collet chucks on 10mm shafts arrived and a plan sort of came together, this morning I spent an hour turning, grinding, polishing and reassembling with the result in the photos.


    I need to check runout with an indicator but it was imperceptible when running in at 200 to 2500 rpm input mounted in a 30mm ER40 collet in the lathe,

    - Nick
    Last edited by magicniner; 27-04-2014 at 07:32 PM.

  2. #2
    How did it get on ?

  3. #3
    It works really well, thanks Lee.
    It's nice to be able to push 1mm endmills through steel and aluminium at a manageable manual feedrate instead of having the mill in top gear with the motor screaming and still worry about breaking tools.
    Next time I strip it down I'll measure it all up and create a solid model, it ought to be an easier build and more durable than the geared speed increasers for which plans are available,

  4. The Following User Says Thank You to magicniner For This Useful Post:

Similar Threads

  1. Safe Z Speed
    By dudz in forum Artsoft Mach
    Replies: 23
    Last Post: 24-05-2014, 04:08 PM
  2. HSM Advisor - High Speed Machining feed & speed calculator
    By magicniner in forum CAD & CAM Software
    Replies: 2
    Last Post: 20-01-2014, 12:57 PM
  3. Speed control
    By Saracen in forum Spindles & Drive Motors
    Replies: 2
    Last Post: 29-12-2012, 02:18 PM
  4. Adjusting speed with vfd
    By motoxy in forum Spindles & Drive Motors
    Replies: 8
    Last Post: 24-09-2012, 04:07 PM
  5. Top speed failing after a bit
    By Robin Hewitt in forum Machine Discussion
    Replies: 6
    Last Post: 12-11-2011, 12:46 PM


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts