Concrete column forming tube having a smooth inside coated surface

A concrete column forming tube for receiving poured concrete therein to produce a concrete column;

• said forming tube comprising:
• an elongate rigid cylindrical tube capable of receiving concrete therein to form a column and comprising spirally-wound plies of paper adhered together and defining an inside wall surface having spiral seam lines thereon, said spirally-wound plies comprising three inside plies having deckled overlapped edges and each having a basis weight range of about 90-100 lbs./1000 square feet and a density range of about 3.6-4.0 basis weight/point, and at least five outside plies having butted edges and having a basis weight range of about 70-120 lbs./1000 square feet and a density range of 2.7-3.5 basis weight/point;
• and
• a centrifugally-cast epoxy resin coating sprayed onto said inside wall surface of said spirally-wound paper tube while said tube is rotating, said coating when sprayed having a sufficiently low viscosity to produce an inside coated surface on said forming tube extending continuously across said spiral seam lines and having a thickness and smoothness sufficient to eliminate spiral seam lines and other undesirable characteristics on an outside surface of said formed concrete column, said epoxy resin comprising about 75-95% by weight low viscosity multifunctional resin and about 25-5% by weight accelerated aliphatic amine catalyst, and said centrifugally-cast epoxy resin coating having a thickness of about 0.010-0.125 inch.