A leading UK manufacturer of measuring tapes, Fisco Toll Limited has taken a step towards better quality assurance by building its own fully automatic laser tape measuring device. It is the only system of this type in the world. The investment allowed for automatic control and scaling of measuring tapes up to 50 meters in length in EC class 1, in the standard which requires an accuracy of 20 microns in the first meter, which is the same accuracy as required for steel rigid a ruler. Reaching Class 1 is a two-step process. The first step is printing in accuracy class 1 and this is ensured by Fisco's own inkjet printing system.

& ldquo; However, we cannot sell Accuracy Class 1 product unless we can prove it & rdquo; - explains Chief Engineer Stan Burton. & ldquo; We needed a system capable of measuring to an accuracy of 20 microns & rdquo ;. To imagine an order of magnitude, for example, a human hair is 70-100 microns and a talcum grain is 10 microns!
In fact, the basic accuracy of the machine after final installation is 1.1 microns per meter & ndash; or about 1/75 of the thickness of a human hair.

The main structural element of the device is the 32-meter Hepco-GV3 linear guide, which has been ground with an accuracy of 0.1mm and a straightness of 0.1mm and these accuracy are guaranteed for a service life of up to 10 years. the main guide of the transport system of the roller with a blade for winding / uncoiling the tape and a roller with a camera with a laser mirror attached.

& ldquo; During the measuring cycle in which the tubes are at rest, full stability is maintained at 1 micron & rdquo; explains Stan Burton & ldquo; It is thanks to Hepco rollers with variable preload that give better stiffness than even the most expensive ball bearing systems. Although the high accuracy of the rollers is possible, thanks to Hepco this was achieved using standard elements. In previous tests, an alternative linear guide was tested on a test length of one meter. & ldquo; Despite the very high price, we could not match the preload & rdquo; continues Stan Burton & ldquo; I was able to push the & oacute; This performance was not enough for Fisco.

Hepco's linear guides were delivered in consecutively numbered four-meter sections, totaling 32 m. "One extra piece was needed much later in the assembly phase". Stan Burton continues & ldquo; And even when this was an added section, the & nbsp; sections fit perfectly & rdquo ;. No couplings could be accepted as even a 10 micron deflection would cause the laser mirror to vibrate and the loss of the light beam and measurement data. Another major benefit of the Hepco guides which was noticed by Fisco were machined surfaces against hardened edge & ldquo; V & rdquo ;. This provided invaluable benefits in mounting replacement components directly on the guide.

& ldquo; Other manufacturers were also considered, but could only offer systems that were much more expensive and much less flexible & rdquo; concludes Stan Burton.

The new laser system is located at the Fisco factory in Rayleigh, Essex, in a specially adapted temperature-controlled room. The Weights and Measures Office has accredited this device, it is also approved and used by Trading Standards (Institute of Commercial Standards). UK) to verify other products of measuring tapes.