Digital instruments are easier to read, but not necessarily more accurate. The Workzone (Aldi) digital caliper is specificed to plus or minus 0.03mm at 150mm, slightly worse than most Mitutoyo professional ones at 0.02mm. IT's the same as the Mitutoyo at 100mm or less. This is mostly due to quantization of the 0.01 resolution. A Mitutoyo vernier caliper is good to 0.05mm so if the Aldi meets it spec. it's more than good enough for car work. Just avoid the "carbon fibre" plastic ones.
Robert G8RPI.
I appreciate the ease of reading.(Even with spectacles, my old eyes are not the best and not up to determining which lines line up on vernier scales, easily).
I try to always bear in mind that not everyone can afford to buy professional quality tools (at professional prices!). The reason I posted this particular 'bargain' was that the cheapest I've seen digital calipers recently was at circa £30 at Machine Mart and similar outlets.
For replacement button cell batteries for this digital calipers, might I suggest Poundworld (Dealz here in Ireland). I'm not saying their batteries are the best but they are cheap.
As someone else said recently, I too, often convert metric measurements into Imperial in order to relate to them. So the above accuracy of being good to 0.05mm, when converted is approx. 0.002in. (2 'thou'), and therefore not insignificant. Worth bearing in mind, if measuring in order to decide what to do with e.g. crankshaft bearings. For checking ovality of a crankshaft journal, (big diameter minus small diameter), this level of accuracy shouldn't matter. Just don't go disagreeing with e.g. an experienced machinist using professional measuring equipment (and who knows how to use them!) probably measuring to an accuracy of 1/10 of the above 'thou' (or the metric equivalent).
Some digital calipers can also be zeroed (while the jaws are extended) having taken a measurement and then take a further measurement. So, for example, you could measure a shaft, zero the display, then measure the bearing in which the shaft runs and this measurement will be the clearance between the shaft and it's bearing. This avoids the need to write down measurements and then do calculations. Alternatively, some digital calipers have a + and - feature allowing readings to be added or substracted as required.
AL.
