The early history of non-metallic flexible conduit has generated a good deal of the questions submitted for OldTIMER as of August 2001 so this page will attempt to address those questions.

 When the terms 7/32” duct, loom, Alphaduct and others are used they all refer to this early form of flexible conduit.  To keep historically accurate and not introduce any current bias into the process, the exact descriptions from page #830 of the 1917 Central Electric Company of Chicago Catalog have been used.  The images shown may be from that catalog or from others that had greater clarity. 

Wireduct   
The inside layer of Wireduct is composed of closely woven canvas, to which lining is cemented a layer of spirally wound fiber strip, which acts as the framework of the tube.  Over this framework is a tightly woven envelope of cotton, which, in turn is coated with a compound containing a large percentage of finely divided mica.  The completed product is tough and substantial and well calculated to protect the wires from mechanical injury.  It will not dry out and become brittle, and offers a smooth raceway for the wires.

Alphaduct  
Alphaduct has a smooth hard interior of heavy canvas duck; this is covered with a weather proof compound over which is spirally wound a special fiber cord.  All interstices between the cord are filled with a special compound, over which a protecting jacket of cotton is braided.  It is finally coated with a flexible weather-proofing compound.  The finished product will stand exceptionally severe moisture tests, is practically non-kinkable, and offers a smooth raceway for the wires.

Circular Loom 
Circular Loom is made by winding heavy Para rubber friction tape over spiral of high insulating fiber.  This framework is then covered with a continuous woven jacket of extra strong canvas.  The entire tube is then saturated thoroughly with weather-proof compound, care being taken that none shall touch the inside fiber, which forms a hard smooth inter surface.  It is finally run through powered mica, which adheres to the exterior of the tube, adding to its insulating qualities.

Loomflex 
Loomflex is a continuous, seamless tube with an interwoven canvaslike interior which is thoroughly soapstoned to aid in fishing the wires.  The inner tube is coated with a moisture and flame-proof compound and is covered with a substantial braiding treated with non-absorbent and flame-proof material.  Loomflex is easy to cut, clean to handle and extremely flexible.  It is light in weight and withstands almost any abuse.

These products come in sizes from 7/32” through 2-1/4”