Abstract: The method of filament winding on a corrugated form to thereby form a cylindrical corrugated part includes the steps ofCausing relative motion between said form and a glass fiber applicator,Wrapping a glass fiber band with a resin coating thereon on said form in a spiral pattern without bridging over said corrugations in said form,Permitting said glass fiber to harden on said form thereby forming said corrugated part, andRemoving said hardened part from said form after a predetermined period of time.The apparatus has a collapsible corrugated form arranged with its axis of rotation substantially horizontal. An applicator is supported for reciprocating fore and aft movement with respect to preselected surface(s) of the form. Proper orientation of the applicator with respect to the form permits a band of resin coated glass fiber strands to be spirally wrapped on the corrugated form without bridging over the corrugations.