This tool is under-marketed, over-priced, and difficult to find, but once you’ve used it, you won’t want to be without one. It solves a problem that nothing else on the market solves: making a drilled hole come out at the right place on the other side of a wall, and I mean a wall where getting to the other side requires a hike.
The PX-10 consists of two handheld units: a transmitter and a receiver. You put the transmitter on one side of the wall, then take the receiver to the other side. The receiver has four illuminated arrows that tell you which way to move it; when all four are lit, it’s exactly lined up with the transmitter. There’s even a hole in the center so you can make a pencil mark. It’s also got a readout the tells you the wall thickness.
The manufacturer says the PX-10 works on walls from 5cm to 1.35m (>4 ft) thick, with a positioning accuracy of +/- 2mm per 200mm of wall thickness.
I bought mine in 2008 while working on a historic masonry building. To run a cable, we needed a hole through an exterior wall 14″ thick, starting in an interior closet and exiting in a mortar joint, not in the adjacent brick. To get from one side to the other, you navigated a warren of interior hallways, descended two flights of stairs, and climbed up several levels of scaffolding. A single measurement with the Transpointer showed us where to drill… and the hole came out spot-on!
I’ve also used the PX-10 when installing thru-hull fittings in boats, otherwise a slow, nerve-wracking job (especially near the waterline). It works well for me, even when the hull is thinner than the nominal 5″ minimum range. If you’re working alone, the transmitter is light enough to stick onto a surface with adhesive putty, which comes with it.
I suspect this tool has a broader market than Hilti realizes; their marketing seems focused on contractors doing core-drilling in concrete. The $600 price tag is hard to stomach; I bought mine when it dropped, briefly, to $200. Perhaps they’ll see the light again.
[The Hilti Transpointer is hard to find, and very expensive. The Magnespot Extended Range Point Finder does a very similar thing, but costs $200. Still, at that price, it's more of a rental tool for most people. The Magnespot works with a high-powered magnet, which is a trick a DIYer can use for thin walls. -- KK]