Linear dimensional variability and tensile strengths of three solder index materials.

This study compared the linear dimensional change and tensile strengths of three indexing materials used for aligning joints to be soldered. Sixty rods 6 mm in diameter and 18 mm in length were made from base metal. The rods were divided into three groups of 10 pairs each, and a simulated solder gap was created between the rods in each pair. Ten simulated gaps were indexed with Duralay resin, 10 were indexed with Relate resin, and 10 were indexed with ZAPIT cyanoacrylate material. Measurements were made of each pair, before and after indexing, and the tensile strength of each indexed pair was measured and recorded. Linear measurements showed no significant difference between any of the groups. However, significant differences in tensile strength were found among all the materials tested.