XB-650i Ram Screw Rebuild Kit Instructions

STEP 1 - Strip down Tool

Remove the following parts to make the XB-650i Tool Body easier to work on:

  • Clamp Arm
  • Clamp Straps
  • Ram Foot
  • Body Window Plug

Ram Screw Retention Parts

It is important to understand how the Ram Screw is retained inside the Tool Body. A full-complement ball bearing is integrated with the Ram Screw as the inner race, and an outer Thrust Bearing Race.  Bearing Balls are inserted and removed through a loading slot machined into the Ram Screw.  A Washer sits below the Bearing Balls, and it is held in place with a spring steel Hog Ring.

STEP 2 (OPTION A) - Cut the Hog Ring

In order to remove the Ram Screw for replacement, the Hog Ring must be removed. There is not sufficient access for retaining ring pliers, but the Hog Ring can be cut with an appropriate grinding bur. A 1/8 shank (Dremel Style) carbide flat cutting cylinder bur with a 1/8" or 3/32" dia. is recommended.

The Hog Ring and Ram Screw are all hardened alloy steel, so a carbide or diamond bur is required (the Washer is just mild steel).  Only the Hog Ring needs to be cut, but to do so all 3 parts will have material removed, which is OK because they will all be discarded when replacing the Ram Screw with the Rebuild Kit.  There should be sufficient access with the window in the Tool Body to make the cut.  

USE CARE not to grind away material on the edge of the Tool Body Window.  Once the Hog Ring is cut, remove the Screw from the Tool Body, and remove the thrust washers and pieces of the Hog Ring.

STEP 2 (OPTION B) - Cut the Ram Screw Hex

The other option to remove the Ram Screw is to cut off the Hex Head of the Ram Screw, if you have the required equipment to do so. An abrasive chop saw, angle grinder, or band saw can be used. The Ram Screw is hardened to HRC 37-45.

It is VERY IMPORTANT to not cut into the top face of the Tool Body. Once the Hex is cut off, remove the Screw from the bottom of the Body.

STEP 3  - Grease the Ram Screw

For all grease operations: White Lithium grease with PTFE additive is used at the factory, but any general purpose bearing grease will work.

Apply grease to the unthreaded shank of the Ram Screw under the hex head, and to the inner Thrust Bearing Race.  Thread the new Ram Nut onto the Ram Screw and apply grease to the ram threads. Drive the Ram Nut down the threads to distribute the grease.  Then apply more grease to the threads and drive the Ram Nut back off.  The threads should be well greased at this point.

STEP 4  - Install the Ram Nut in the Ram Foot

A new Ram Nut is provided with the Rebuild Kit.  Remove and discard the old Ram Nut.  Apply grease surfaces of the Ram Foot as subsequently shown, and install in the Ram Foot as shown.

The Ram Nut can only be installed/removed on the "Long (Maxi) Side" of the Ram Foot. There is an enlarged opening on that side that is just big enough to get the Ram Nut through. The Ram Nut does not have a front or back side.

This is a good time to apply new, fresh grease to the Ram Foot Cavity as well. No more than 0.60 oz (17.6 ml, 3.5 tsp) of grease should be used to refill the Cavity. This will correspond to roughly 24% of the cavity volume being filled with grease. If too much grease is used, excess will squeeze out with the next use, and potentially impair tool function.

STEP 5  - Install the new Ram Screw

Insert the Ram Screw into the Tool Body and install the Thrust Bearing Race as shown.

Use the back end of the Hog Ring Loading Tube (the side that does not have the Hog Ring Mounted) to push and fully seat the Thrust Bearing Race inside the Tool Body.

STEP 6  - Insert the Bearing Balls

Rotate the Ram Screw so that the ball loading slot is facing the window in the Tool Body. Carefully insert the (15x) Bearing Balls into the bearing race slot one at a time; tweezers are the best tool for this task. Push the balls around the raceway and rotate the Ram Screw back and forth to get the balls to move and make room. The grease will help the balls stick to the raceway.

STEP 7  - Insert the Washer

Insert the Washer, using the back side if the Hog Ring Loading Tube to fully seat it against the Thrust Bearing Race.

STEP 8  - Insert the Hog Ring Loading Tube

The Hog Ring is pre-loaded onto a special installation tool that allows you to place it all the way inside of the Tool Body, just under the Washer.

STEP 9  - Push the Hog Ring into the Groove

Keep the Ram Screw Hex firmly seated against the Tool Body, and use a pick or small flat head screw driver to push the Hog Ring off of the Installation Tool and onto the Ram Screw Shaft, just under the groove.  You can rotate the Installation Tube to reveal other areas of the Hog Ring to ease it off of the Tube End.  Once free of the Tube End, firmly push the Hog Ring with the Installation  Tool to seat it into the groove.  It should snap into place very distinctly.

STEP 10  - Reinstall all Parts of the XB-650i

Insert the new Body Window Plug, and re-install the:

  • Ram Foot
  • Clamp Arm
  • Clamp Straps