MI-250 GO-TO
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RA EXTENSION ADAPTER

  IF YOU MAKE AND USE THIS RA EXTENSION ADAPTER IT IS ABSOLUTELY IMPERATIVE THAT YOU REALIGN THE RA WORM GEAR MESH AFTER INSTALLING THIS ADAPTER. YOU MUST DO THIS IN ALL 4 QUADRANTS WITH A FULL LOAD.  THIS IS BECAUSE THE 2 INCH EXTENSION WILL CHANGE THE WORM GEAR MESH, DUE TO FLEX.  IF YOU DO THE ALIGNMENT OF THE RA AND DEC WORM GEAR MESH CORRECTLY, THERE SHOULD BE NO DAMAGE TO THE BEARING, OR GEARS BY THIS MODIFICATION. 
YOU DO THIS MODIFACTION OF THE DEC ASSEMBLY AT YOUR OWN RISK.  THERE IS NO MANUFACTURE TO GET YOU OUT OF TROUBLE ANYMORE. 

  1. Here are pictures of the adapter I made.  In the top view, the 4 smaller holes are tapped for 1/4-20 threads.  The threads go about 1 inch deep.  These same holes are drilled from the reverse side with a 5/16 drill bit about 1 inch deep, just to the bottom of the threads.
  2. The 4 larger holes are 9/32 holes drilled all the way through, then countersink with a bit large enough to allow the heads of 1/4-20 hex bolts to drop down to the bottom of the countersink. I used 1.5 inch long 1/4-20 hex bolts through these holes to fasten this adapter to the RA Assembly.


  3. The next drawing is not to scale, The hole diameters are given in decimals.

    All the holes are at 2.35 inch radius from center.
    For a true size drawing you will need a DXF program. Here's DXF drawing adapter file. Here is a free DXF viewer Now I started with this drawing from Larry. Saddle Plate Mounting Holes


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