Of course laser levels are no more accurate than a level + long straight edge since it all comes down to the bubble. Best long distance level is a water tube. I made one from a old bit of hose with some clear plastic tubes I had (eprom carriers to be precise). You need a good seal and to make sure there is no air trapped as you fill it (i.e. raise both ends so it is a smooth curve down and back up. With that I can get say a 10m wall level +/- 1mm.
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Malcolm
Malcolm Reeves BSc CEng MIEE MIRSE, Full Circuit Ltd, Chippenham, UK
Malcolm
Malcolm Reeves BSc CEng MIEE MIRSE, Full Circuit Ltd, Chippenham, UK
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