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Part 3- Grinding Spindle



 (Message from the author: This is a continuous article intended to be updated by myself as new and better information is compiled. Any comments or additions for my article, please contact This email address is being protected from spambots. You need JavaScript enabled to view it.. If your information can be of help to these articles, I will include the information and your name. If you do not want your information or name included let me know. James Long)

 Getting Started:

For the first test I removed the wheel guard and drive belt, plugged it in and turned on the motor, the motor ran quiet and smoothly. I turned the grinding wheel spindle by hand and it was smooth so I put the belt on and tested the rotation of the spindle under power, it runs smoothly. (Replace the drive belt. These old belts have been sitting on the shelf and are dried and hard. Replacement belts can be purchased from Grainger, part #1KLV9).

Started- 12/11/14

Grinding Wheel Spindle (Spindle):


·        The spindle allows mounting and rotation of cutting wheels of various types.

·        The feed knob allows the user to feed the grinding wheel in or out while maintaining the position of the Indexing Head.

·        The wheel can be extended out if the Index Head is hitting the Wheel Guard.



 ·        Total travel of the spindle quill in and out is .350”.

 ·        Wheel arbor diameter .750”

 ·        Wheel Arbor Thread diameter .708” (18mm)

 ·        The thread pitch is somewhere between 24 & 26 TPI (SAE) or between .9 & 1.0 Metric?

 ·       The micrometer dials are divided in metric increments. One complete revolution  of the Spindle Dial is 1.0 mm. The collar of the dial includes a .005” marking, it is not the same distance as the standard marks on the collar and most likely should read .0005”. (Photo #002)

 ·      The lost motion in the screw was about .004”.

 ·      Tightening the Spindle Lock Knob moves the spindle about .002”.

 ·        I made a 4” diameter Aluminum Disk to mount as a testing tool to check the squareness of the spindle to the Main Axle. I found the main axle to be 2.5 degrees “out of square” from the spindle.

 ·        Replaced the Key-way Travel Set Screw and Dial Lock Screws.

 ·        Made replacement spindle lock pin.

 ·        Chased Rotational Lock Pin Hole Thread (mm 10- 1.5) and made a screw-cap to keep the hole covered.



Removing the Spindle:

 ·        Remove the plastic cover and swing the Index Head out of the way.

·      (Photo #003) Loosen the 6-1mm set screw allowing you to remove the End Knob, remove the Micrometer Collar. (Photo #004)



 ·      Using a 5mm hex wrench to remove the 10-1.5mm Spindle Travel Set Screw on the top of the machine (see photo #001). Loosen the Spindle Lock Screw and pull the Spindle out from the grinding wheel end.                  (Photo #005)








Good news, looking inside the casting you can see a lot of Cast Iron supporting the spindle head.

(Photo #006- #007). This is a good time to blow out the inside of the casting.


·       My Spindle did not travel inward enough to allow the Spindle Rotational Locking Pin to properly drop in place and lock the Spindle for changing the grinding wheel. I milled the Travel Control Slot .090” longer. A new Travel Set Screw will have to be made to match the new, cleaned-up slot. (Take care not to machine off more than is needed as this will allow the Spindle to travel beyond its bearing surface.)(Photo #009).



     While the spindle was centered on the mill I drilled a shallow witness mark to help in alignment on re-installation. (Photo #008 - #012)






 ·        Clean, inspect and put the Spindle back into position.

 ·       After replacing the Spindle, the knob was binding at one spot on the dial. After a painfully long trial and error I discovered that the casting was not parallel the the grinding wheel arbor. This caused the Collar to tilt and bind when tightened. This was adjusted by shimming the knob collar (on mine it needed .010” (Photo #011).


     After discussing the problem with machinist friend Bernie, he said, “back up the dial with a felt washer, tighten and adjust until the the collar does not bind.”







 ·      To remove the backlash play from the spindle, I made a part to hold a spring tension against the screw.(Photo #010)





 ·     The screw and spindle are lubricated with Super Lube Grease and re-assembled.








Terminology of parts Disclaimer:

Several names of the parts have been taken from the Deckel Catalog; to insure you the reader, will always know what part I am referring to. I have applied the identification of parts from other machines, catalogs and some I created for a clear description of the parts function, (eg. Top Slide Tool Holder).