Established in 1964 and currently employing 30 people, the firm specialises in close tolerance work in difficult-to-machine materials such as obscure grades of stainless steel, titanium, high nickel content alloys, and plastics. Industries served include aerospace, defence, medical, instrumentation and optronics.

Having this extra thread whirling power and rigidity allows Ottaway to produce up to 4.5 mm deep threads at high helix angles in a single pass on its bar-fed Traub lathe. Standard materials can be machined in typically half the time and hard or tough metals can be tackled with comparative ease right up to the available 200 mm length, according to managing director, Luke Ottaway.

He adds that on multi-start threads there are no discernible witness mark at the many points where machining recommences and so the surface integrity on the flanks of the thread is maintained. This is essential on medical implants to insure against the ingress of bacteria.

Good surface finish and absence of burrs makes thread whirling particularly suitable for medical components. Traub says that thread milling or hobbing will take up to four times longer and single-point chasing up to 10 times longer – if the thread can be cut at all.