Method of making a cast guide for folding flexible sheets

Abstract

The invention relates to a method for producing a guiding device for flexible materials in which an element, representing the actual guide passage to be produced, is made with the aid of a malleable material; the element is positioned in a mould which has the general shape of the outer contour of the device to be produced; a resin is cast inside this mould and onto the element, and the malleable material constituting the inner element is then eliminated with the aid of an agent which has no action on the resin.

What I claim is: 
     
       1. A method of making a guide for forming a length-wise folded flexible web comprising: providing a flat sheet of malleable material, leaving flat one end of said sheet, folding generally length-wise said malleable material adjacent the other end thereof so that said material adjacent said other end has folds corresponding to desired folds of said folded flexible web while also folding said malleable material intermediate the two ends so as to form a gradual transition between said flat one end and folds of said material adjacent said other end; placing the malleable sheet material in a mold with the ends of the malleable sheet material extending through the ends of the mold; casting and hardening a resin inside the mold and about both sides of the malleable sheet material; and eliminating the malleable sheet material.   
     
     
       2. Method according to Claim 1 in which the malleable material is affected by chemical agents and the step of eliminating the malleable sheet material comprises the application of a chemical agent to the malleable sheet material to destroy it. 
     
     
       3. Method according to Claim 1 in which the malleable sheet material is wax. 
     
     
       4. Method according to Claim 1 in which the malleable sheet material is lead. 
     
     
       5. Method according to Claim 1 in which the malleable sheet material is an impregnated cloth. 
     
     
       6. Method according to Claim 1 in which the malleable material is thermoplastic and the step of eliminating the malleable sheet material comprises heating the thermoplastic malleable sheet material to melt it. 
     
     
       7. Method according to Claim 6 in which the resin is an epoxide resin and the rise in temperature during the solidification of the resin eliminates the thermoplastic malleable sheet material.