Measuring wheels have been around for hundreds of years, and still operate on the same basic principle: a wheel has a known circumference, so that each time it completes a full revolution, a certain fixed distance can been recorded.
In many cases, they offer accuracy within 1 percent, with specific wheels designed for road, rail and indoor use, and have the ability to measure in metric, imperial, or both units.
But after generations of widespread use, are measuring wheels still the best option for every application?
The beauty of the measuring wheel, and the root of its enduring appeal, is its low cost simplicity. Regardless of whether it is used for a national railway survey or to plot a show jumping course for a local gymkhana, it requires no specialist training and costs relatively little in comparison to its competitors.
Whether a measuring wheel is up to the job, however, all comes down to the numbers – specifically your measurements and your project costs. Firstly, a measuring wheel’s suitability can be weighed up by the level of precision needed to attain your results. Secondly, if the budget on a project is much larger, then it may be worth investing extra money into alternative technology.
For instance, in road, rail and land engineering works, ample project budgets often merit the use of more advanced measurement equipment, such as a total station. Large budgets can also shoulder the associated costs of using something other than a wheel, for example the purchase/hire costs of a unit or contracting a trained operator.
However, if pinpoint accurate results are not the objective of the project (for instance, an overland survey for a proposed new road or rail route) then it is still completely feasible to use a measuring wheel. In the same way, if your project budget is capped, a measuring wheel offers a value for money solution – they are cheap to purchase and can be used by anyone, without the need for costly, formal training.
If your project is not cost sensitive but demands precise measurements you may wish to consider an alternative to the wheel. However, alternatives also have their limitations so it’s worthwhile to weigh up the pros and cons associated with using any measurement device. Let’s take a look at two of the wheel’s closest competitors: the laser measure and the total station.
Laser measure
A laser measure is a handheld measuring device that produces highly accurate digital results over short distances. Entry-level lasers are priced comparatively with measuring wheels but the most sophisticated units can run into the hundreds of pounds. With a lower maximum range – often to within 200m, compared with a wheel’s 9,999.9m – a laser measure also requires an ‘end point’, a solid surface such as a wall or floor, to generate a result.
It is the ideal choice if you require accurate results in confined spaces (estate agents regularly use them to measure room dimensions, for example) or over short distances (for instance, an electrician plotting a cable run) but useless over open ground or when recording mid to long distances. Unlike the laser measure, the simple push and go functionality of a wheel doesn’t restrict you to working in straight lines. Corners, curves and undulations can all be tackled effectively with a measuring wheel – if you can push over it, the wheel can measure it.
Total station
Chances are, where there’s a surveyor, there’s a total station. You might not have heard of it but you’ve probably seen one several times, an inconspicuous little unit sitting atop a tripod. Don’t be fooled, the total station might not look like much but it is one of the most, if not the most, sophisticated measurement tools on the market today.
Able to take horizontal and vertical measurements with its inbuilt electronic theodolite and record distances with its electronic distance meter the total station returns very accurate results over long distances, precise to within just a few millimetres over a kilometre or more. Like the laser measure, the total station also requires an end point or reflector to generate a result and, like its diminutive cousin, it can only measure in straight lines.
The functionality of the total station may sound simple enough but operators are required to undertake specialist training to get the most out of one. In contrast to the push and go functionality of the wheel, simple enough for anyone to achieve good results, the total station remains the preserve of qualified surveyors who charge a hefty premium for this highly technical service.
Price point is also a major consideration with the total station and, while the issue of training might not preclude you from choosing one, the cost just might. Total stations, even reconditioned units, retail for thousands of pounds. Expect to pay a couple of thousand for a basic second-hand station and in excess of ten thousand pounds for a brand new, top of the range unit. In comparison, a professional-grade measuring wheel can be purchased for around £100 and, for occasional lightweight use, you can find even cheaper models.
For a surveyor or civil engineer who takes long distance, straight line measurements regularly, the total station is a worthwhile investment – in terms of accuracy there is nothing to beat it – and to provide a return on investment a trained station operator can be contracted out for between GBP500-800 a day. For the rest of us – be it landscape architect, farmer, site manager, rail technician or sports umpire – the measuring wheel is hard to beat in terms of user-friendliness and cost.
So, in summary, let’s ask the question again: are measuring wheels still the best option for every application?
Ask yourself instead is anything technically better than a measuring wheel? As we have seen, the answer is yes, there are technologies capable of producing a more accurate result – the laser and the total station are more precise over straight line distances, and are suitable for both big budget and cost sensitive projects.
However, if the question is are measuring wheels still the best option for everyday applications? then the answer is also a resounding yes! In terms of versatility, use in compact or open spaces, over curved routes, without previous training or experience, use without an end-point, and general value for money measuring wheels are unbeatable and, even on the tightest of budgets, they put the best overall solution well within reach.