Engis UK, offers customers a tooling solution which effectively replaces the expensive and skilled “black art” of honing, putting the process firmly into the range of repeatable and cost-effective machining centre tasks on standard vertical and horizontal CNC equipment.

The tooling’s design overcomes issues caused by lack of height within many machining centres, and removes the need for floating toolholders and adaptors (enabling the bore finishing tools to be held directly in the machining centre toolholders), while still providing the required high-accuracy geometry demanded of bore-finishing operations, e.g. roundness to within 1 µm and surface finish to 0.2 Ra.
Using Engis’ flexible tooling system, the first tool passes through the bore with a single in-and-out stroke, and its place is then taken by the pre-set, single-pass tool. The number of tools used in any given application will vary depending on the amount of stock to be removed, the surface finish, the geometry and the material being machined.
Each of the new Engis pre-set, single-pass bore-finishing tools is coated in a single layer of diamond, which is permanently plated on to the tool, creating faster cutting/stock removal rates and ensuring that tool sizes can be held for long periods without adjustment.
For further information www.engis.com

Galvanometers for laser-beam steering and scanning in surgical, analytical and other applications include a precision-machined housing in which the stator moves. At the Poole factory of Westwind Air Bearings, which manufactures galvanometer components for its US parent group, Novanta, these coil housings are CNC-turned from mild-steel bar to within grinding tolerances.

Dimensional accuracy is down to 5 µm, while surface roughness of the bore and outside diameter are Ra 0.4 and 0.8 µm respectively. It is curious then that such precise components are subsequently rumbled in batches of up to 400 in a pair of vibratory bowls supplied by PDJ Vibro.
Nevertheless, by developing a viable production route that incorporates vibratory finishing, Westwind has been able to save a lot of time and money in comparison with manual finishing. In addition, the uniformity of finish is better using the automated procedure as each component is processed consistently rather than being subjected to the inconsistencies of hand deburring. In total there are 12 part numbers, two-thirds of which are required in relatively high volumes of 3000 per week.
John Bradley, senior manufacturing engineer, says: “Fine fettling of the housing by hand, together with washing cycles before and after finishing, took three people five hours, i.e. 15 operator-hours, to complete a batch of 100 housings.”
Today, it is normally team leader Martin Graham who processes the components in the PDJ Vibro vibratory bowls in a two-hour cycle, without the need to wash the parts at all. They go straight to plating after a quick air blast to remove any media resting in the bore. Overall there is a 7.5-fold saving in labour cost compared with hand processing, and a 60% reduction in finishing lead-time.
For further information www.vibratoryfinishing.co.uk