Holding all the aces

Remember the days of clocking up the vice using a DTI (dial test indicator) mounted on a magnetic base? Those above a certain age will recall the agonies of watching the needle flicker intolerantly, insisting upon further fine adjustments to the vice, usually courtesy of a few taps from a soft mallet. Thankfully, today's workholding solutions are designed to sidestep the vagaries of manual adjustment, offering speedy set-up and simple, modular operation, without any compromise to precision. A case in point is the VB Dock Lock quick change, zero-point workholding/ palletising system from Micron Workholding (01480 861321), an innovation that claims job changeover can be achieved inside two minutes. Machines or tables are fitted with a VB Dock Lock base unit, with fixtures featuring plugs that allow simple docking and immediate machining. The patented collet-locking system is based upon a series of cylinders that allow any configuration of base plate/set-up stations. VB Dock Lock offers benefits such as: set-up alterations parallel to machining; work interruption at any time, without losing 'zero-point'; zero-point repeat accuracy of less than 5 micron; and 5-face machining, without unclamping. Available in various sizes, VB Dock Lock variants offer up to 90 kN retention force and pull-in force up to 30 kN per unit. Image: VB Dock Lock quick change, zero-point workholding/ palletising system - an innovation that claims job changeover can be achieved inside two minutes MULTI-FUNCTIONAL Today's production environment is dominated by small batches and frequent set-ups. For this reason, WNT (0800 073 2073) has developed the ZSG 2 range of multi-function vices, which can clamp a multitude of component shapes with minimum changeover time, largely thanks to its modular design. Image: WNT (UK)'s ZSG 2 range can clamp a multitude of component shapes with minimum changeover time Take the ZSG 2's carrier jaws fitted with revolving jaw inserts, for example. Users can machine different profiles on each of the four jaw faces, then quickly rotate the jaw, ready for the next operation. For further adaptability, the ZSG 2 vice can be fitted with a universal adaptor plate with ten M12 holes on their surface that allow a range of clamping elements to be located. Another interesting workholding innovation is the new three-in-one jaw system from Kurt Workholding, which is said to increase the versatility of any of the company's standard 15 cm vices, making it suitable for small batch sizes and prototype work. The easy-to-use bolt-on jaw system, available in the UK from CIS (01480 225850), features a series of pre-set patterns with aligning pins. The jaws hold components accurately, as with conventional jaw plates, and permit aggressive machining, while clamping at different angles. According to Kurt, the jaw system is "a better and more cost effective option than building a special fixture". In terms of chucks for milling operations, now available from Gewefa (01225 811666) is the MX high speed milling chuck, which is said to offer strong gripping power. Gewefa claims it gives 100 per cent more gripping torque (compared to a 16º collet system) as a result of its smaller taper angle and a nut-free design that minimises centrifugal force and vibration at high speeds. Its design, where the collet is drawn into the chuck body from the back, provides uniform all-around clamping and ensures fine run-out. The slim design minimises interference issues and enables precision machining into hard-to- access pockets, particularly when milling. FIVE-AXIS WORKHOLDING For those struggling to get to grips with workholding solutions for 5-axis milling applications, the Roemheld (0121 453 1414) 'try-before-you-buy' initiative is enabling end users in aerospace, Formula One, medical and automotive to test the benefits of its 5-axis vice technology. The majority of applications deploying Roemheld 5-axis vice and jaw technology are gripping safely on 3 mm. This has resulted in many production engineers having to rethink how they machine components for optimum productivity. In some instances, being able to grip on 3 mm has resulted in a saving of up to 30 per cent on raw material per component, says Roemheld. If 5-axis machining creates workholding dilemmas, so does machining miniature parts. However, System 3R (02476 538653) is offering a solution via its new Twist Lock direct-clamping chuck, which is based on the GPS 120 chuck with a repeatable accuracy of 2 micron. Image: Twist Lock – a solution to 5-axis dilemmas Specifically for precision milling, the automated loading of round and square metal blanks can be quickly and accurately achieved. Pneumatically operated, at the touch of a button the four clamps rise and twist, releasing the workpiece by an ejector function. A new workpiece is then positioned by a robot gripper and the clamps re-engage. No clamps need to be unscrewed, so what could have taken up to 40 seconds now only takes around 4 seconds, says System 3R. Also aimed at small parts machining, the new QwikStak modular sub-plates are the latest addition to the versatile Chick System 5 workholding system from 1st MTA (0800 783 0510). QwikStak has been developed to provide a simple and cost-effective method of converting larger clamping systems, such as Chick's 1550 series QwikLok and MultiLok HMC units, into high density workholding systems for small components. Image: Chick QuikLok, converted into high density clamping units with QwikStak modular sub-plates Through its ability to be removed and remounted on the base unit in seconds, QwikStak also provides an effective pallet changing system that both minimises loading and unloading time, and provides seamless changeovers between jobs. With regard to turning operations, coming up with better ways to grip round parts is a challenge. However, Hainbuch has been demonstrating its creative talents with the release of its Mando Adapt and Jaw Adapt system, which allows companies quickly to transform a standard Hainbuch collet chuck into a mandrel for internal workpiece fixturing or into a large capacity jaw chuck. ALL NEEDS COVERED Compared with traditional separate chuck set-ups for multi-turning tasks, MandoAdapt and JawAdapt give operators a three-in-one lathe workholding system to cover all chucking applications at greatly reduced changeover times. Available in the UK from Leader Chuck (0121 771 4843), the system is designed exclusively for use with the Hainbuch collet chuck and is guaranteed within 5 µm TIR. Image: MandoAdapt and JawAdapt give operators a three-in-one lathe workholding system For users of vertical lathes, production engineers should consider the InoZet clamping system developed by HWR Spanntechnik (available from Thame Workholding, 01844 208050), which has been developed for the machining of large ring-type workpieces. By converting a standard 3-jaw chuck to a 6-jaw chuck, the clamping forces are distributed more evenly around the workpiece. This contributes to reduced distortion of the workpiece and to a significant improvement in machined roundness: for instance, out of roundness on a 610 mm turned diameter is reduced from 0.2 to 0.03 mm. Image: InoZet, developed for the machining of large ring-type workpieces Box item Self-centring vice Erowa says it has a way of making life simple for machine operators/setters when milling with high feed rates, using its new self-centring vice, which is available from REM Systems (01452 314100). Working with an integrated pallet, the system can be set up while machining operations are in progress, ready for exchange once the machine comes to a halt. Image: The Erowa self-centring vice, making life simple for machine operators/setters The Erowa self-centring vice offers 16 kN of clamping power at 60 Nm torque on the spindle, while maintaining repeatability of ±0.01 mm. First published in Machinery, November 2010