Assembly 3: Internal Hose Adapter

Schematic:
Similar to a Super-Soaker, the idea is to eliminate the external hose and wand configuration of a traditional flamethrower in favor of a more compact handheld design. In order to accomplish this, the nozzle is connected directly to the outside of the pressurized frame.
However, this introduces problems in feeding – the distribution of the liquid in the frame will vary based on the amount remaining, orientation of the weapon, etc. To counter this, a long hose is connected from the nozzle and fed down to the bottom protrusion of the frame, ensuring relatively continuous output.


Assembly Itself:
Some of the parts here require minor modification, and some nonstandard connection. However, the modifications are minor and do not require any ab initio machining.
(There is no overview picture below for the first part of the assembly, because of a slight design change obsoleting the initial picture.)

Parts:
2” Plug x 3/4” FIP PVC
1/2” MIP x 3/8” Socket PVC
1/2” Socket x 3/4” MIP
3/4” FIP Hex Coupler
3/4” MIP x 3/4” Hose Barb
1 1/2” MIP x 2” Socket PVC
1 1/2” FIP x 2” Plug PVC
3/4” Hose Clamp
3/4” ID Hose

Tools & Supplies:
Hacksaw
Utility Knife
PVC Primer & Cement
Epoxy
Teflon Tape
Strap Wrench
Adjustable Wrench
Vise and/or Clamps
Flathead Screwdriver

Assembling the Parts:
Start by taking the 2” Plug x 3/4” FIP PVC fitting and carefully carving a slight chamfer on the inside of the threaded connection.

 

Next, use the hacksaw to cut off all but a quarter inch or so of the socket on the 1/2” MIP x 3/8” Socket PVC fitting. Use the utility knife to provide a slight angle to the outer edge of the remaining stub.


Prime both the cut-down stub and the inner face and first quarter-inch of the threads of the larger fitting, and then use PVC cement to glue them together, applying pressure as needed with the vise or clamp.
Next, use PVC cement to attach the socket portion of the 3/4” MIP x 1/2” Socket PVC fitting over the exposed male threads. As this is a nonstandard connection, epoxy is used afterwards to cover the outside of the joint and add strength.

  

The picture below summarizes the parts and tools for the remaining assembly process.


Connect the 3/4” hose barb to the inside of the PVC fitting assembly via the 3/4” FIP coupler, using Teflon tape on the threads. Again, epoxy may be used on the outside of the seals to add strength.

 

Cement the assembly so far inside the 2” Socket x 1 1/2” MIP PVC fitting. Then, screw the 1 1/2” MIP threads into the 1 1/2” FIP x 2” Plug PVC fitting. This plug will be cemented into the frame later. The threaded attachment between the hose/nozzle assembly and the frame will allow for the removal of the adapter without destructive disassembly of the frame of the flamer.

  

With the adapter completed and ready for mounting to the frame, use the hose clamp to firmly attach one end fo the 3/4” ID hose onto the hose barb, and then screw the manual nozzle into the outside of the adapter.
Note that if the hose has an ingrained bend to it, try to orient the manual nozzle so that the valve handle is in the plane of the curvature – this will make it easier to thread the hose inside the frame while retaining some exterior ergonomics.

 
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