The finer resolution allows more complex tools to be produced and minimises subsequent hand polishing, cutting two to three days off the typical lead-time of 15 working days from order to delivery.

The new DMLS machine is an EOSINT M 250 Xtended from EOS, Warwick. It has significantly boosted CRDM's toolmaking activities to around one third of turnover, according to Mr Bennett. "During the three to four years that we were using the previous DMLS machine, we made around 80 tools, " he said, "whereas the new machine produced 100 tools in the first five months of operation."

In the past, CRDM often had to fall back on conventional metalcutting, both high-speed milling and spark erosion, in about 50% of cases. Consequently lead-time was up to two weeks longer, particularly if EDM electrodes had to be made.

Using the Xtended version of the machine, conventional toolmaking now accounts for only one third of mould throughput, and falling.

Rapid tooling by DMLS is ideal for lower volume, higher added value work, in particular, for complex tooling requirements where a lot of sparking would normally be needed. "During the building of an injection mould, for instance, conformal cooling, gates and feeds, ejector pin holes and fixing details can all be included into one operation, exerting marked downward pressure on cost and lead time."

www.crdm.org.uk