Metal Detector Choices
Advice on shopping for metal detectors able to find metal in a sawlog — before your blade does. March 3, 2006
Question
We recently purchased a 36" band mill and are now looking to purchase a metal detector to scan logs for metal (nails, wire, etc) before sawing. Can anyone recommend specific brands and types we should look at?
Forum Responses
(Sawing and Drying Forum)
From contributor F:
I don't know what they cost, but I would check into the ones surveyors use to find buried markers. I resawed some salvaged lumber for a guy once and he borrowed a metal detector from a surveyor friend. He found every single nail in the beams.
From contributor P:
I think there is a company located in Oregon that sells a high end detector made just for the timber industry. There should be some older posts in the Knowledge Base. I use a mid-grade coin hunter's detector (had it before the mill purchase) and it works well for me.
From contributor D:
As a consultant, I worked with Metal Detectors, Inc. They make good log and cant scanners and have been good to work with when somebody had a problem.
From contributor T:
We have and use daily the Probe 2100 from Metal Detectors. You will need metal-free ground underneath the logs to scan on - it picks up the rebar in concrete.
From contributor P:
I have a Schoenstedt ga-92 metal locator which I use for surveying. It cost about $800, which is a typical price for a survey grade metal locator. Schoenstadt is the leading brand in survey metal locators.
I have not tried it on logs yet, as I am sawing my own nail-free pine, but I'm fairly confident it could find most nails in logs. It can find a small nail buried 2 feet underground fairly easily.
You would have to get the logs at least 10 feet from any other ferrous metals (the mill, vehicles, tractors, etc) for it to work properly. It would also pay to keep track of the butt logs so you don't waste time searching for nails in logs that were high up in the tree.
From contributor J:
I have much experience with metal detectors, and I also own a mill. The detector you want is one that has power! One with a fairly wide coil. One unit that is fantastic for this type of application is a Fisher Gold Bug. It has the power to read an iron nail over a foot deep, with no discrimination circuit to get in the way. I don't know about all survey detectors, but the guy that I hired had a pinpoint detector, with a very narrow coil, and you have to be within an inch to get it to read a target. They do go deep, but almost totally worthless for finding a nail in a log. It would take forever. I fired up my Goldbug, and found the survey stake in 2 minutes after waiting for a half an hour for the surveyor.
The Goldbug has the power to quickly sweep over a log, and find it if it is there.
The comments below were added after this Forum discussion was archived as a Knowledge Base article (add your comment).
Comment from contributor M:
I’ve found RENS Metal Detectors to be the most reliable. They work on an analog system so they don’t give off the false trips like I experienced with the digital units.
