Aluminum cores are mass produced, thin-walled aluminum spiral pipes, designed to replace paper fiber cores. Aluminum sheets are corrugated, then spiral formed using a lock seam to join sheet edges at any diameter with the flexibility of spiral forming. At 16" I.D. aluminum cores weigh 0.19 lbs/in. as opposed to paper cores which are 0.73 lbs/in for a 1/2" wall thickness. Currently cores being produced range from 24"-72" long with an I.D. of 16" and 20”. Cores can be produced at a rate of 4 ft./min. Aluminum cores are made from 3XXX alloy making them 100% recyclable.