Laser Level

An Eccentric Anomaly: Ed Davies's Blog

Following a short Twitter conversation with @littletinhouse I too got myself a new toy in early December, a Stanley Cross Line and 90° Laser Level. I like it.

Actually, I think it was a bit cheaper than the current price when I bought it: upper £70s.

My experience is that if I buy tools because they look like they'll be useful I never actually use them but something bought for one particular purpose ends up being used all the time. The main purpose here is establishing the floor level position on the posts. Within 10 or 20 mm vertically that's a bit of an arbitrary choice so long as all the posts are consistent so I just used the laser to mark a point at the same height on each then worked out where the holes for the joist bolts should go relative to that.

It actually turned out that the points I'd marked were a plausible choice for the heights of the lower of the two bolts on each so I just went with that.

But since doing that I've found a few more uses which, while not allowing anything I couldn't have done before, did make things a bit quicker and more accurate.

The biggest problem with this device, though, is that it doesn't really work in bright daylight, let alone full sun. That's not too surprising, of course, as anything bright enough to compete with the sun reliably would be frying people's retinas a bit too often.

To get the levels on the posts I popped back up to the site once it had got dark. My pocket phone camera is quite good in daylight, considering its age and size, but doesn't do dark very well even in the appropriate mode. Still, here's the laser cross on a main post with the horizontal beam on the stub post to its north:

Wandering round with my head torch selected to white (rather than red!) light allowed pencil marks to be made on each post at the same level. I did it with the laser attached to a photo stand which needed two positions to cover all the main house posts (the full length of the house was just too far even in the dark - the beam got a bit fat for accuracy) with the transfer of level being done by lining up on the marks made on the intermediate posts.

In not-very-bright daylight it's quite possible to use the laser over short distances. Of course, the point is to use it over longer distances - putting something reflective as a target helps. Here I'm establishing a centre line for holes in a post which previously I'd done using a long spirit level as a straight edge measuring half the width of the timber at each end. Shining the laser on the far end of the post is both quicker and more accurate:

… using the metal ruler part of a set square both to measure where the far vertical line should be and also to reflect it back to make it visible from shallow enough angles.

Of course, for something like this you don't want a mirror-like surface which could produce a confusingly aligned image. The more specular reflection of a steel ruler seems about ideal.