Minelab PRO-FIND 40 Review: Ferrous Tone ID, and a Missing Depth Figure

It removes a guess. A plain pinpointer tells you where the target is and nothing else, so on an old house site or a farmyard you enlarge the hole for every signal, and most of those signals are nails. A probe that gives one response for ferrous and another for non-ferrous lets you leave the nail where it is and move on, and across a day on iron ground that is a meaningful number of holes you did not dig, and did not have to refill to the standard the hole filling guide sets.

Two supporting features matter as much as the headline. DIF, which Minelab publishes as Detector Interference Free technology, reduces the interference between the probe and an operating detector, which is what stops your machine screaming every time the pinpointer comes near the coil. And the vibration indication matters more than it reads: on a windy beach or beside a road, a probe you can feel is a probe you can use without headphones. Five sensitivity levels then let you turn the whole thing down in mineralised soil, which is the setting most people never touch and should.

Only published figures appear below. The gaps in this table are the point: Minelab publishes very little in tabulated form for its pinpointers.

Read this next to the price. Within one range, the cheaper model publishes more about its waterproofing than the flagship does.

Compare the two listings side by side and the problem is obvious. The Minelab PRO-FIND 35 at $99.00 publishes DIF technology, a ferrous tone ID with two responses, five sensitivity levels, audio and vibration indication, and full waterproofing to 10 feet or 3 metres. The Minelab PRO-FIND 40 at $149.00 publishes DIF technology, a ferrous tone ID with two responses, five sensitivity levels, audio and vibration indication, and a full waterproof housing with no depth stated. The feature list is the same and the cheaper model is the one that tells you how deep you can take it. Unless your retailer can point to a published figure that separates them, the 35 is the better buy from the same range, and the pinpointer roundup sets both against the rest of the field by price.

The second weakness is the depth silence itself. A waterproof housing with no number is not a rating, and on a tool you will push into wet sand and hold under water while you fan a hole, a number is what you want. Garrett publishes 20 feet for the Pro-Pointer AT and Nokta publishes 200 feet for the Nokta PulseDive Pinpointer. Both are more useful statements than a housing description, and the Minelab waterproof ratings page shows how carefully this maker normally publishes exactly this figure elsewhere in its range.

Third, a ferrous tone is an aid rather than an oracle. A rusted iron object can read non-ferrous, a large nail lying flat presents differently from one standing on end, and a good target sitting against iron will often sound ferrous. Use the tone to skip obvious nails on trashy ground, not to talk yourself out of digging a repeatable signal your machine liked, which is the point the signal reading guide keeps making.

Published owner reviews are consistent that the ferrous tone earns its place on iron-heavy ground, and equally consistent that it takes a few hunts to trust. The second recurring theme is DIF: owners moving from a cheap probe report that their detector stops reacting to the pinpointer, which is a nuisance most people assume is unavoidable until it is gone. The vibration indication also draws repeated praise from people hunting near roads and in wind.

The complaints are the price against the Minelab PRO-FIND 35, the 9V battery rather than a rechargeable cell, and a detection field some owners find longer than they expect, which is a retuning habit rather than a defect. As with any probe, a Pinpointer Belt Holster at $13.99 is the accessory that stops it being lost, and Minelab owners running an Minelab Equinox 700 or Minelab X-Terra Pro report the DIF benefit most clearly because those machines and this probe are designed around each other.

Buy it if:

• You hunt old house sites, farmyards or any ground carpeted with nails.
• You want vibration as well as audio, for wind, traffic noise or hearing loss.
• You run a Minelab machine and want the interference reduction DIF publishes.
• You want five sensitivity levels to tame mineralised soil.

Skip it if:

• You can buy the PRO-FIND 35 instead, which publishes the same features and a depth rating.
• You dive, where the Pro-Pointer AT and the PulseDive publish real depths.
• You hunt clean parks, where ferrous identification solves a problem you do not have.
• You want the cheapest route to stopping blind digs.