SHEAFFER VAC FILL REPLACEMENT SEAL SEATING TOOL (RZ Tool)

The RZ Tool comes with the metal tool and 5 O-rings + 5 soluble plastic washers. Packs of 10 O-rings/washers available for purchase. 
The steps for replacement are as follows:

1) Remove the old seal which consists of a hard plastic washer over a toroidal felt packing that is about 3/32" thick. This is done by using a ¼" drill bit and going no more than ¼" deep (lest you punch-out through the back of the barrel) and then using a bent 90 degree probe (the D13 micro probe is ideal for this) and/or a ¼" reamer to clean the cavity out to make room for the new seal. Be very careful how deep you go so as not to come through the back of the barrel. Insert your drill bit into the barrel before you start and use a thin strip of masking tape placed ¼" above where the bit comes out of the open end of the barrel so you know the limits of how far in you can drill into the back end seal. And don't go that far in right away; go maybe half that far and work with the pick and reamer to get the old seal out and get a good, cleaned out cavity down there for the new seal. If you're good (and lucky) sometimes you can pop the hard plastic cover off the seal, pull it out, and fish the felt out all in one or two pieces. The JL droplight with its tiny LED is ideal for internal inspection during this process. If available, install our RZ-B drill guide into the open end of the pen barrel.

2) Place an O-ring on the end of the RZ tool with the thinner diameter and push the assembly into the cavity you've just made in the back (seal) end of the barrel. Pull the RZ tool out and verify with the drop light that the O-ring is flatly seated at the end of the barrel and that it is centered and is not turned sideways.

3) Now you place a white soluble plastic washer on the other end of the RZ tool that has the larger of the two end diameters. This fit is looser than that with the O-ring, so you may have to hold the pen barrel vertically and insert the assembly upwards into the barrel. Push the tool with the plastic washer on it into the barrel on top of the O-ring, turn the whole assembly over so the seal end of the barrel is down and pull the tool out. Again use the light to verify that the plastic washer is flat, centered, and not sideways.

4) Holding the barrel with the open side facing vertically up. Use a pipette to put one or 2 drops of acetone on top of the O-ring / white soluble plastic washer (butyrate)/ pen seal cavity sandwhich. Maintaining this vertical position, set the barrel aside, in something like a knock-out block and let it dry out overnight. You should think about doing the acetone work outdoors as it isn't healthy to breathe.

5) To get the pen's plunger shaft through the new seal the first time, you may need to put a dollop of silicone grease on the tip of the shaft before forcing it through.

6) It should be mentioned that there is a tool available (D9, an improved version of an old Sheaffer tool) with a wooden handle and a shaft the same diameter as the Vac Fil shaft with a dimple on the end. Insert the dimple end of the D9 shaft into the outer hole in the barrel that the threaded shaft will eventually come through from the inside. This is intended to help you align the threaded back end of the Vac Fil shaft with the hole in the seal end of the barrel to simplify this tedious operation. You may want to have one of these laying on your bench during the above operations. It is shown on this web page as RZ (that stands for Ron Zorn, who invented it).  

7) The RZ tool comes with (5) O-rings and (5) soluble plastic washers. Additional sets of 10 available.
8) So the other tools you may want to have on your bench while doing this are our RZ-B,  D9 Shaft alignment tool, RZ Drill and RZ Reamer.  Or D13 pick, JL Drop light, silicone grease and a pipette make this restoration much easier. 

Other Tools Descriptions:
RZ-B: USED TO CENTER THE DRILL BIT THAT IS USED TO REMOVE THE OLD PACKING FROM THE BARREL OF THE PEN. FITS INTO THE OPEN END OF THE BARREL, THEN GUIDE A DRILL BIT THROUGH IT TO REMOVE THE OLD PACKING AND SEAL.
RZ Drill: 1/4" DRILL BIT FOR REMOVAL OF OLD SHEAFFER VACUUM FILLING PEN SHAFT SEALS.
RZ Reamer: 6 FLUTE 1/4", Flat ended REAMER FOR CLEANING OUT THE HOLE AFTER DRILLING OUT THE OLD SHEAFFER VACUUM FILLING REAR SEAL. (You don’t want a centering reamer, as the centering tip may knock the shoulder off the inside hole for the shaft).
VAC FILL SEALS: VITON/FKM O-RINGS AND BUTYRATE WASHERS FOR REPLACING SHAFT SEALS ON SHEAFFER VACUUM FIL PENS. These go with the RZ tool, above. The butyrate washer dissolves on top of the O-ring and glues it in. 10 each of the o-rings and the washers.

BACKGROUND: This tool was developed over 10 years ago by pen repair pengineer Ron Zorn (thus the part number designation 'RZ'). He came up to my table at a pen show about a year ago and expressed the belief that it would be a good move for the pen repair community if I manufactured and made this tool available. I should also mention Nathan Tardif who developed the technique of Vac Filler seal replacement with an O-ring and a soluble plastic washer used as an adhesive to hold the O-ring in place (this tool is used for that installation). This method is an evolutionary advancement over Father Terry Koch's method of using an orange foam washer to do the same. The problem with that method was that in a few years the foam seal would begin to harden and fall apart. Nathan's method uses an O-ring seal made from a material that is extremely durable in this application.

Note: Although very similar, the Doric filling system uses different materials.  The acetone used in this process will do great damage to a Doric barrel.