Apparatus and methods for use with a baffle support fixture for a machine assembly of the tubes and baffles in a bundle assembly of a shell and tube type heat exchanger. The bundle comprises tubes inserted through baffles. The bundle is assembled using a holding fixture that includes anti-rotational features to secure baffles in a desired orientation. Following assembly, the bundle assembly is temporarily fixtured using pressure applying means such as plates and rods, and is then permanently affixed using an adhesive composition. After adhesive is applied, bundles, with the pressure applying means still attached, are preserved on racks and heat treated to cure and permanently set the adhesive.