HYTAC®-B1X and XTL are thermoplastic-based syntactic foams. Due to the thermoplastic base, both B1X and XTL are extremely tough and durable. Unlike traditional syntactic foams which require inserts, B1X and XTL can be direct threaded. For all other HYTAC® materials, CMT recommends use of slotted inserts bonded into the base of the plug. We have worked with machine shops and toolmakers to develop a series of best practices for both direct threading and insert installation. Our insert installation guide offers complete details.
For direct threading, we developed a tensile test and used our in-house material testing equipment to record the results in pounds force. B1X and XTL were tested. For inserts, what we have found is that direct scored aluminum inserts work very well. Some of the key success factors for this simple process include the elimination of coolant during cutting (for proper adhesive bonding) and face milling the bottom of the plug after insert installation (to ensure a flush mating surface for the plug to the base is created). We typically recommend Loctite 495 for bonding and our pull-out test results were based on this adhesive.