Aluminum plunger tube upgrade for Acorn Signet (OOD Kit)

This upgrade replaces the plastic Out of Darts plunger tube with an aluminum one. It also includes a longer Plunger Rod for a more reliable catch.

In addition to the original Signet parts and hardware, you will need:

• A 70mm length of aluminum tubing (28mm OD, 26mm ID). 

• Two O-rings (26mm OD, 21mm ID). One each for the ram and plunger.

• One Dash 016 O-ring (3/4" OD, 5/8" ID). I used a leftover from another kit.

• One Dash 012 O-ring (1/2" OD, 3/8" ID, from the original OOD hardware kit)

• A centerpunch, a 1/8" drill bit, power drill, superglue, Loctite 242 (blue or equivalent).

• A 25mm length of 1.75mm diameter filament. (Optional: 2mm diameter, 20mm long dowel pin)

Step 1. Print plastic parts
Print the Ram, Plunger, Plunger Rod and Tube jig. (4 walls, 100% infill). Use the same orientation as the original Signet files.

Step 2. Drill M3 thru holes in the Aluminum Plunger Tube.
Use the Tube jig on the aluminum tubing to locate, centerpunch, and drill a 1/8" (or 3mm) hole on each side. You may want to use electrical tape to fix the jig in place and sharpie to mark the locations for the centerpunch. The third, larger hole in the model is not needed for this upgrade.

Step 3. Assemble the Ram.
Seat the original small O-ring from the Signet kit into the tip of the Ram. Superglue a 26mm OD, 21mm ID O-ring into the base of the Ram. Install two brass heat-set inserts into the Ram.

Step 4. Assemble the Plunger.
Seat the second 26mm OD, 21mm ID O-ring into the side of the Plunger. Superglue the Dash 016 O-ring into the front face of the Plunger to pad Plunger/Ram interface. Attach the Plunger to the Plunger Rod using a length of filament, or the optional 2mm dowel pin.

Step 5. Assemble the Blaster.

1. Lubricate all O-rings.

2. Insert the main blaster spring and Plunger/Plunger Rod assembly into the catch until it clicks into place. The "blaster" should be primed. 

3. Insert the Ram and aluminum plunger tube into the blaster (over the plunger) , making sure to align the M3 thru holes in the plunger tube with the M3 heat-set inserts in the Ram. 

4. Install the Slide over the Plunger Tube assembly and fasten the Slide, Ram and Aluminum Plunger Tube using the M3 flathead screws included in the hardware kit. Use Loctite 242 or equivalent and turn until finger tight. 

Congratulations! You have upgraded your Acorn Armaments Signet. Enjoy!

These remixed parts are an upgrade to the Acorn Armaments Signet. The upgrade includes an aluminum plunger tube with larger internal capacity than the original “metal tube” version of the blaster. I used the Out of Darts hardware kit, and upgraded with these parts.

The upgraded plunger also accepts a Dash 016 O-ring to be used as padding for the Ram/Plunger interface.