10 Metal Detecting Mistakes Beginners Should Avoid
Every detectorist makes mistakes when starting out.
Metal detecting looks relatively simple from the outside: switch on the detector, walk across a field or beach, wait for a signal and dig up something interesting.
In practice, there is quite a lot to learn.
At Metal Searchers, we have more than 30 years of detecting experience, and many of the mistakes below are ones that almost every detectorist encounters at some point.
Fortunately, most are easy to correct.
Here are 10 of the most common metal detecting mistakes beginners should avoid.
1. Detecting Without Proper Permission
This is the most important mistake to avoid.
Being able to walk onto land does not automatically mean that you are allowed to metal detect there.
Before detecting on private land, obtain permission from the landowner or another person who genuinely has authority to grant it.
This includes:
- Farmland
- Pasture
- Woodland
- Private estates
- Gardens
- Paddocks
- Privately owned beaches
Public land can also have restrictions.
Public footpaths, parks, commons and open-access land do not automatically provide metal detecting rights.
What to do instead
Before detecting:
- Identify who owns or controls the land.
- Obtain permission.
- Agree which areas you may search.
- Agree how finds will be handled.
- Check for archaeological or environmental restrictions.
Where practical, a written agreement is preferable.
For more information, read our guide to getting permission to metal detect on private land.
2. Buying a Detector That Is Too Complicated
Beginners sometimes assume the most expensive detector must automatically be the best first detector.
Not necessarily.
A high-end detector may offer:
- Multiple frequencies
- Advanced discrimination
- Adjustable recovery speed
- Ferrous limits
- Complex audio profiles
- Numerous search modes
Those features are extremely useful when you understand them.
But for a beginner, they can also create unnecessary confusion.
If you spend the entire session wondering whether you have configured the detector correctly, you are not learning efficiently.
What to do instead
Choose a detector that:
- Suits where you intend to detect
- Fits your budget
- Comes from a reputable manufacturer
- Has straightforward controls
- Gives you room to learn
- Has good documentation and support
The best beginner detector is one you can learn thoroughly.
Our Metal Detecting for Beginners guide explains what to consider when choosing your first machine.
3. Running Sensitivity Too High
This is one of the most common technical mistakes.
Many beginners assume:
More sensitivity = more depth = more finds.
Unfortunately, it is not that simple.
If sensitivity is too high for the conditions, the detector may become unstable.
You may hear:
- Random chirps
- False signals
- Unstable Target IDs
- Responses caused by mineralised ground
- Electromagnetic interference
A noisy detector can actually make weak genuine targets harder to recognise.
What to do instead
Increase sensitivity until the detector starts becoming unstable.
Then reduce it sufficiently to restore reliable operation.
A stable detector at sensitivity 20 can be much more useful than an unstable detector at 30.
Don't worry about whether another detectorist is running a higher number.
Ground conditions vary.
4. Swinging the Search Coil Too Fast
Metal detecting is not a race.
Sweeping rapidly across the ground can reduce your ability to hear short or difficult target responses.
It can be particularly problematic when:
- Targets are close together
- Iron contamination is high
- Targets are deep
- Recovery speed is relatively low
What to do instead
Use a controlled sweep.
Keep the coil moving steadily and listen carefully.
When you hear a questionable signal:
- Slow down.
- Shorten the sweep.
- Centre the target.
- Approach it from another direction.
Often a poor-sounding target becomes much clearer once you investigate it properly.
5. Lifting the Coil at the End of Every Sweep
This is sometimes called pendulum swinging.
The search coil starts close to the ground in the centre of the sweep but rises at both ends.
That creates an arc.
The result is that you lose detection depth at exactly the point where one sweep should overlap the next.
What to do instead
Keep the search coil:
- Low
- Level
- Parallel to the ground
throughout the entire sweep.
Imagine sliding the coil across an invisible flat surface.
Do not deliberately press it into the soil, but keep the height reasonably constant.
Good coil control is one of the most valuable skills a detectorist can develop.
6. Relying Too Much on Target ID Numbers
Target ID is extremely useful.
It is not infallible.
A beginner may learn that a particular coin normally produces a certain number and then decide only to dig that number.
That can result in good targets being left behind.
Target ID changes because of:
- Target depth
- Target orientation
- Ground mineralisation
- Nearby iron
- Corrosion
- Target size
- Multiple targets
- Search coil position
A coin lying flat in clean ground can give a very different response from the same coin standing vertically beside an iron nail.
What to do instead
Use all the available information:
- Audio
- Target ID
- Signal repeatability
- Target depth
- Ferrous indication
- 2D Target Trace where available
- Response from different directions
When you are learning, dig more questionable targets.
That is how you discover what your detector is actually telling you.
7. Ignoring Ground Balance and Electrical Interference
If a detector becomes unstable, beginners often immediately reduce sensitivity.
That may help, but sensitivity is not always the cause.
The problem might be:
- Incorrect Ground Balance
- Mineralised soil
- Electrical interference
- Power lines
- Another detector
- Loose coil connections
- Wet conductive ground
What to do instead
Try to diagnose the cause.
If the problem changes as you raise and lower the coil over clean ground, investigate Ground Balance.
If the interference continues even when the coil is held stationary away from the ground, electromagnetic interference may be involved.
Use Noise Cancel or frequency adjustment where your detector provides it.
Our Metal Detector Ground Balance guide explains this in more detail.
8. Digging Poorly and Leaving Holes
Bad recovery technique can quickly damage a detecting permission.
Large untidy holes are particularly problematic on pasture because they can:
- Damage grass
- Create trip hazards
- Injure livestock
- Upset landowners
What to do instead
Learn to recover targets neatly.
On suitable grass:
- Pinpoint the target accurately.
- Cut the smallest practical plug.
- Place removed soil carefully.
- Recover the target.
- Return all soil.
- Replace the plug.
- Press it firmly back into position.
When you finish, the hole should ideally be difficult to see.
On beaches, refill the hole before moving on.
9. Throwing Rubbish Back Into the Ground
You will dig rubbish.
Lots of it.
Typical finds include:
- Foil
- Ring pulls
- Nails
- Wire
- Aluminium fragments
- Shotgun cartridge components
- Farm machinery fragments
- Bottle caps
It can be tempting to throw rubbish into the nearest hedge or back into the hole.
Don't.
What to do instead
Carry a finds pouch with a separate rubbish compartment.
Take all metallic rubbish home and dispose of it properly.
There are several benefits:
- You won't detect it again next time.
- Sharp metal is removed from livestock areas.
- The landowner sees responsible behaviour.
- The site becomes slightly cleaner.
Removing rubbish is part of good detecting practice.
10. Cleaning Finds Too Aggressively
This is one of the easiest mistakes to make and one of the hardest to undo.
A newly discovered old coin may be covered in soil and corrosion, and the natural reaction is to make it clean and shiny.
That can permanently damage it.
Aggressive cleaning can remove:
- Patina
- Surface detail
- Plating
- Inscriptions
- Archaeological deposits
- Evidence useful for identification
What to do instead
If a find appears potentially old or significant:
- Photograph it before cleaning.
- Record exactly where it was found.
- Remove only loose soil if necessary.
- Avoid acids and abrasive cleaners.
- Seek identification advice where appropriate.
If the object could be archaeologically important, contact your local Finds Liaison Officer.
For coins, see our guides to cleaning ancient Roman coins and cleaning rare coins safely.
Five More Beginner Mistakes Worth Knowing
Although this article is called “10 Metal Detecting Mistakes”, there are several additional mistakes worth mentioning briefly.
Expecting Treasure Immediately
Most detecting sessions do not end with a hoard.
You will probably find plenty of:
- Lead
- Buttons
- Aluminium
- Modern coins
- Iron
- Unidentified fragments
That is normal.
The first few outings should be treated primarily as opportunities to learn the detector.
Changing Too Many Settings at Once
If you change:
- Sensitivity
- Recovery Speed
- Ground Balance
- Discrimination
- Audio
- Frequency
all at the same time, you will not know which change helped or harmed performance.
Change one setting at a time.
Then test the result.
Blindly Copying Someone Else's Settings
Settings published online can be useful starting points.
But another detectorist may be using:
- Different soil
- Different search coil
- Different targets
- Different EMI conditions
- Different firmware
- Different detecting technique
Understand what each adjustment does rather than copying numbers blindly.
Our Minelab Manticore Coin Settings article, for example, provides the settings we use but also explains why we use them and where they may need adjustment.
Not Recording Interesting Finds
A coin without a findspot has lost part of its story.
For anything historically interesting, record:
- Date
- Field
- Approximate or precise location
- Detector
- Depth where useful
- Photograph
For important archaeological finds, accurate location data can be extremely valuable.
Giving Up Too Quickly
Some detecting sites are quiet.
Some fields produce very little for several hours.
Then one signal changes the whole day.
Equally, a quiet site may genuinely contain very little.
Experience teaches you when to persist and when to try somewhere else.
Don't judge your detector - or the entire hobby - by your first few outings.
Beginner Mistakes at a Glance
| Mistake | Why It Matters | Better Approach |
|---|---|---|
| Detecting without permission | Risks legal problems and damages trust | Get permission first |
| Buying an over-complex detector | Makes learning unnecessarily difficult | Choose a suitable beginner machine |
| Excessive sensitivity | Creates noise and false signals | Run the highest stable setting |
| Sweeping too quickly | Can miss difficult targets | Slow, controlled sweep |
| Lifting the coil | Reduces effective depth | Keep coil low and level |
| Trusting Target ID completely | Good targets can read differently | Combine ID with audio |
| Ignoring Ground Balance/EMI | Causes instability | Diagnose the source of noise |
| Poor digging | Damages land and permissions | Recover targets neatly |
| Leaving rubbish | Harms sites and reputation | Remove all metallic rubbish |
| Aggressive cleaning | Can permanently damage finds | Identify before cleaning |
A Good Beginner Detecting Routine
A simple routine avoids many of these mistakes.
Before detecting:
1. Confirm permission.
2. Check that the site is not protected.
3. Charge your detector and pinpointer.
4. Start with a straightforward factory search mode.
5. Perform Noise Cancel if appropriate.
6. Ground Balance where required.
7. Set sensitivity to a stable level.
While detecting:
8. Sweep slowly, low and level.
9. Investigate signals from different directions.
10. Dig plenty of targets while learning.
After detecting:
11. Refill every hole.
12. Remove rubbish.
13. Record interesting finds.
14. Show significant finds to the landowner.
15. Report archaeological or potential Treasure finds where required.
Frequently Asked Questions
What is the biggest beginner metal detecting mistake?
Detecting without appropriate permission is the most serious mistake. Technically, running sensitivity too high and poor search-coil control are among the most common problems.
Should beginners use maximum sensitivity?
No. Use the highest sensitivity that allows the detector to remain reasonably stable.
How fast should I swing a metal detector?
Use a controlled sweep appropriate to your detector and search mode. Avoid rapid swings and keep the coil level throughout the sweep.
How close should the search coil be to the ground?
As close as practical without constantly striking the surface. Unnecessarily raising the coil reduces effective detection depth.
Should beginners dig every signal?
Not literally every signal, but beginners should investigate a wide range of targets. Digging teaches you how different objects sound and behave.
Can Target ID tell me exactly what is underground?
No. Target ID is an indication, not a guaranteed identification. Depth, orientation, nearby iron and ground conditions can all influence it.
Why is my metal detector constantly making false signals?
Possible causes include excessive sensitivity, incorrect Ground Balance, electromagnetic interference, loose connections, mineralised soil and conductive wet ground.
Should I clean old coins immediately?
No. If the coin could be historically or financially important, identify it before carrying out aggressive cleaning.
Do I need permission to metal detect on a public footpath?
A right of way does not automatically provide a right to metal detect or dig. Appropriate permission is still required.
Is metal detecting difficult to learn?
The fundamentals are straightforward, but becoming skilled at interpreting difficult signals, dealing with iron and adapting to different ground conditions takes practice.
Final Thoughts
Most beginner metal detecting mistakes have one thing in common:
trying to progress too quickly.
Don't worry about finding the deepest target.
Don't worry about copying advanced settings.
Don't worry about having the most expensive detector.
Instead:
Learn your machine.
Listen to the audio.
Control the search coil properly.
Dig a wide variety of targets.
Get permission.
Fill your holes.
Record interesting finds.
And give yourself time to gain experience.
After more than 30 years in the hobby, we still learn something from detecting sessions.
That is part of what makes metal detecting so enjoyable.
The next signal could be rubbish, a modern coin or something that has been waiting hundreds of years to be found.
You won't know until you investigate it.
Happy detecting!