Ultrasonic Measurers

[Thomas Mc Cann]

Got the Fein version of the Ultrasonic measuring device but found it a=20 big disappointment. (This unit throws a laser beam to enable one to=20 ensure it is oriented correctly). Consistantly inconsistant. Repeat=20 measurements way out. Measurement from one wall across the room varied=20 from measurement from opposite wall. Even a measurement taken at 8ft=20 height across an open plan office was impossible to get reliably.

Have I got a duff unit ?

Are their tips and wrinkles on using these things ?

Bosch make a unit which apparently uses the laser beam to establish the=20 distance but at about =A3282 its a bit rich for me.

Any advice ?

Paul Mc Cann

[Malcolm Stewart]

The ultrasonic beam will be much wider than the laser pointer beam, and will pick up from a range of objects. It may also be disturbed by draughts, unless some special wizardry is employed. Get yourself the basic Leica Disto and get measurements to better than 3mm.

[Andy Dingley]

The Fein is a little disappointment. In comparison, cheapies like the Stanley are the big disappointment.

These things are basically useless. Maybe for measuring spacing between trees along a French country road, maybe for measuring rough room sizes as a flat-letting agent (unfurnished lets only). For anything else though, they're a little imprecise and hugely inaccurate.

[PoP]

I agree about accuracy, however if you are buying floor coverings such as carpet, or wall coverings such as wallpaper, you generally aren't bothered about exact measurements and even a 5% inaccuracy is no big deal. I think the one I've got is supposed to be accurate to less than

1cm over quite a long distance - and that's generally good enough for my needs when buying materials!

Also very good (I understand) if you are doing calculations for CH system design. You generally overstate the losses by a safe margin anyway to ensure you've got the right size radiator/boiler so accuracy is again no big deal for room volume.

And there are some situations where it is just plain difficult to impossible to do a physical measurement. Calculating loft flooring area for example - can be done but it might involve climbing into the loft first. With one of these devices you can poke it thru the loft hatch and get a close enough reading.

Not exactly useless IMHO!

PoP

[tpaul]

Have you actually tried this?

If it wouldn't work across an open plan office I can't see it working in a loft.

The real bug bear is the inconsistancy and the inability to work out how/why the thing is mis-reading

Paul Mc Camm