Composite Materials | Industrial Laminates | Machined Components | Composite Tubes

A Monumental Task

One of the more unusual requests that Attwater has recently received was for 165mm thick epoxy glass industrial laminate – which is considerably thicker than the usual orders for laminates.

There were two main challenges:-

  1. Working out how to handle and process such a large quantity of material
  2. The sheer thickness of the finished product and being confident that it was cured all the way through

“We quickly established that we would actually be able to get the 330mm stack of impregnated sheets into the daylight of the press in the first place,” said technical development engineer, Matt D’Arcy. “So our attention then turned to ensuring the heat penetration was adequate all the way through the stack without overcooking – epoxies can be at risk of something called thermal runaway if you’re not careful”.

The solution was ingenious, and one that Mary Berry would be proud of. Having embedded a thermocouple in the middle of the stack to monitor the core of the laminate, the press was brought slowly up to temperature and held. The stack was covered in tin foil to keep the temperature in and to help the heat penetrate.

“We used the same technique as if we had been baking a giant cake” explained Matt. “The thermocouple confirmed we had the correct temperature penetration and because we’d taken into account the cutting pattern, we made sure the metal was in one of the offcuts.”

The finished sheet weighed around half a tonne and the client was delighted with it!