Homemade metal detector

[AtomRat]

How are you going with the detector HunterHarvey? I ordered the Surf P.I as well, probably wouldn't if I knew it was a beach detector at first, but having a go at a detector should be a good project for any of us. It seems to be a couple of standard components, some 555 timers and a NAND schmitt and two pots.

Heres what I got in the mail from the kit:

 

[HunterHarvey]

G'day FGS,

glad to hear some positive feedback for this idea on this site, have seen others say don't bother it is a BFO detector so on and so forth, just go out and buy one, that is great if you have the money, exactly what I would do otherwise I think, in saying that though it will be ever so satisfying to have built something that works from the ground up so to speak and actually find something, gold would be awesome though

Joao, I sure will use it for prospecting, so long as I can detect the coins that I have the missus scatter around the yard, if it doesn't pass that test I won't worry about taking it out in the field.

DrBean, thanks for that heads up, I was a little intimidated about the coils, mind you, I will have help if this one works well, and I am happy with the results, I might do exactly as you suggest look for a pi kit on ebay

AtomRat, I am yet to receive the kit, I hope I will get it some time this week, I won't be able to work on it till next weekend at the earliest though sadly, your kit looks quite a bit more technical than the one I am getting from talkingelectronics, will be a good starter kit though, looking forward to playing around with it though. When did your kit arrive? have you started assembly yet? I will be keen to see how yours goes, I live right near a beach so would be perfect for going for a walk on the sand

Cheers

HH

 

[AtomRat]

If you are new to electronics, it is not really a hard thing to do. I suggest you buy a couple of 'basic kits' from Jaycar and maybe even one of their "Short Circuits" books, #1, #2 & #3. You can buy things online from them as well at http://www.jaycar.com.au. The Surf P.I 1.2 kit I got I would consider very basic.

It took 3 weeks to come to me from the UK, I only took that photo today and won't start it for a little while as I am pretty busy. I will let you know when I start / complete the kit. Unfortunately I'm not close to the beach, so I don't know where to test it haha

You could make the board from talkingelectronics if you wanted to. But you would need to go to Jaycar again and order the components, and a blank fibreglass PCB board that you can etch the circuit into with Press n Peel film, a toner printer and transfer method, or using a Sharpie pen and etchant like ferric chloride. If you want to know more about this, feel free to ask.

As I mentioned, before attempting a board, read some basic electronics as even for that 'basic' circuit you are getting, you still need to know how to place capacitors correctly ( capacitor polarity identification. ) If it sounds all technical and complicated, it isn't.

 

[for_Golds_sake]

Hi AtomRat

Would love to know your thoughts on the Surf Pi once you have built it and tested it.
The biggest problem I had (and still have) is trying to build a housing for the coil.

I am still trying to figure out an easy way to build a DIY one. However if that doesn't work out I think I might go with one I found on ebay recently. Can't post links yet, but if you search 'metal detector coil housing' you will see them. Not sure about the quality, but they don't seem too expensive.

If anyone has any thoughts on how to build a DIY coil housing would love to hear them.

 

[AtomRat]

Hi AtomRat

Would love to know your thoughts on the Surf Pi once you have built it and tested it.
The biggest problem I had (and still have) is trying to build a housing for the coil.

I am still trying to figure out an easy way to build a DIY one. However if that doesn't work out I think I might go with one I found on ebay recently. Can't post links yet, but if you search 'metal detector coil housing' you will see them. Not sure about the quality, but they don't seem too expensive.

If anyone has any thoughts on how to build a DIY coil housing would love to hear them.

I've seen somewhere around a person buying a cheap $10 plastic wall clock and using it as a coil housing, even plates and pot plant bases.
I'd personally make a vacuum formed HDPE plastic housing when I get around to it. There would be many ways to make the housing, even a resin filled mold, it's up to what you can do and which one you like. If it is too hard to make, then yes, just buy one. But I would not be expecting anything too great from these kits

 

[Goldtarget]

Hi AtomRat

Would love to know your thoughts on the Surf Pi once you have built it and tested it.
The biggest problem I had (and still have) is trying to build a housing for the coil.

I am still trying to figure out an easy way to build a DIY one. However if that doesn't work out I think I might go with one I found on ebay recently. Can't post links yet, but if you search 'metal detector coil housing' you will see them. Not sure about the quality, but they don't seem too expensive.

If anyone has any thoughts on how to build a DIY coil housing would love to hear them.

I reckon you are in the right place to pick up a old faulty or dead coil that could be repurposed and used? Just my first thoughts.

 

[Guest]

The other simple method other that using a old coil is using a skid cover' cut two shaft ears from a square plastic down pipe and hot glue them to the skid plate along with the coil' then fibre glass resin fill it. Squirt of non metallic paint and presto'

 

[Tathradj]

Hi,
I bought a SM PRO PI kit of Ebay 2 days ago.
I have a few ideas on building so when I get time I will post some ideas up.
This is going to be interesting.

 

[HunterHarvey]

Hi all,

Just a quick one, I will be working on my detector next weekend, I plan on taking as many photos as I can and will post it up here with preliminary test results. Got my kit today, put it beside my watch so you got an idea on the size of the kit.

Cheers

HH

 

[Drbean]

Hey guys use very thin plywood make 2 round circles and sandwich the coil windings in between then put a bead of silicon around outside and glue to supports on top to hold stem . I used black riser tube for water garden sprinklers for stem it's cheap and very stable flattened two sides with a file and drilled hole . You can get it at burnings in various lengths in plumbing section. I made my coil out of enamel copper wire from Jaycar .3 thickness mono construction. I found it ok on air tests but terrible on any minimized ground. Modified connection and fitted dd coil tech with a sad connector big difference .mate if your tight for dosh look up matchless in detector very easy to make works well on beaches , dd coil not a bad machine at all.Dr

 

[Drbean]

Tath mate sm pro is a great kit that's the one I used watch out for the pots very cheap ended up replacing all of them with Jaycar units as I had trouble with ones in kit the supplier is a good guy and will be happy to help if you need help to convert to dd coil let me know easy as to do.Dr

 

[joao garimpeiro]

Good luck HunterHarvey!
I'm looking forward to the result

 

[joao garimpeiro]

Hi DrBean,
excellent Tips!!

 

[for_Golds_sake]

Thanks guys

Those are some awesome tips on how to make a coil.
I will definitely have a play and see what I can put together. I will let you know how I go.

 

[Tathradj]

Thanks for that.
My kit is currently sitting in Kentucky at the US Customs sorting centre.
I have a few class d amp boards plus pots to fiddle with so am looking forwards to piecing it all together.

Tath mate sm pro is a great kit that's the one I used watch out for the pots very cheap ended up replacing all of them with Jaycar units as I had trouble with ones in kit the supplier is a good guy and will be happy to help if you need help to convert to dd coil let me know easy as to do.Dr

 

[gcause]

Here was my first attempt at a DIY metal detector a few years ago, a BFO detector, I called it the MYLAB GC-4600 :8

It slowly evolved:

Here is a PI detector I made from a kit:

Here is the air test:
[video=480,360]http://youtu.be/LONTElIYFP8[/video]

Heres the build thread:

http://golddetecting.4umer.net/t6394-grant-s-diy-pi-detector

I also show how to build your own coils with the pin outs so you can use standard connectors and shop bought coils with your DIY metal detector:

I also show how to make your own circuit boards:

Hope it helps you guys with building yours

 

[for_Golds_sake]

Thanks gcause.

Those are some great photos and instructions - will be a big help.
Have you tried using it in the goldfields? I'm thinking of trying mine in Bendigo and wonder what your thoughts are?

Even if it just find lots of bullets, it's great fun building it!

 

[gcause]

Thanks gcause.

Those are some great photos and instructions - will be a big help.
Have you tried using it in the goldfields? I'm thinking of trying mine in Bendigo and wonder what your thoughts are?

Even if it just find lots of bullets, it's great fun building it!

I hope it goes well for you.

I didn't have any luck with my copy of a Surf PI detector on the gold fields, it had real trouble with the mineralisation couldn't get it stable.

Your BFO should work well on the beach but I don't know how you will go on the highly mineralised ground at Bendigo. Just have to try it and let us all know how you go.

Best of luck with it.

 

[joao garimpeiro]

Hi mate,
I enjoyed the project!

 

[Tathradj]

It just arrived this morning.
I will post up photo's along the way so stay tuned.
The pots seem quite firm but I will check the sweeps with a meter
just in case.
Going to enjoy this one.

Tath mate sm pro is a great kit that's the one I used watch out for the pots very cheap ended up replacing all of them with Jaycar units as I had trouble with ones in kit the supplier is a good guy and will be happy to help if you need help to convert to dd coil let me know easy as to do.Dr