Building a drag coil / specialised vehicle for dragging.... your thoughts?

So I want to build a specialized vehicle to use with a drag coil specifically in the Leonora area because it has a lot of open areas with little or no scrub. I am looking to spend a LOT of time using this vehicle looking for big gold only, so I am willing to spend a bit of money on it getting it right.

VEHICLE
Originally I was planning on using an ATV, however I wanted a vehicle with lots of ground clearance, and preferably air conditioning. I am planning on buying a new car anyway so it will likely be one of the following vehicles... whatever I get, it will have front and rear diff lockers, winch, etc. I figure wherever I can fit an ATV I can fit a car. Obviously I will only be able to drag in sparse low vegetation areas, but should still be able to cover plenty of ground relatively quickly:

Car possibilities:
- Jeep Wrangler with 3 inch lift kit
- Landcruiser 79 Series with 3 inch lift kit

TIRES
I have two options here, my main issue is getting sufficient traction in mud while at the same time being 100% puncture proof, the latter being the trickiest to achieve.

Option 1: Buy a set of these tractor tires which are 10 bias ply with massive treads: Model BKT 567 (35 inch tires). These tires have a really deep mud tread and a thick central area of the tread to handle harder rocky areas. If I use these tires I can get really close to creeks in heavy mud. If I choose these tires, I will need to get custom steel rims made up to handle the large bead of the agricultural tire ($285 per rim).


Option 2: Is to buy a set of 37 inch Mud terrain tires which normally would be staked and go flat in no time, however I am thinking of using a Flat Proofing system called Tyrfil which is a two part liquid that is poured into the tire, which sets to make it completely solid (no air). The benefit of this stuff is that it is flexible like jelly and gives a ride just like an air tire and I can also pre select the required equivalent PSI for the tire, I can make the tires equivalent to 10 PSI for example. I have been promised from the Tyrfil company that my tires will never go flat and that they will last "Until the tread wears out"... but $450 per tire. With these tires, I can use standard Alloy or Steel rims... Because the Tyrfil flat proofing product is so heavy (as heavy as water filled tires) I was planning on using a 22 inch rim so I can use lower profile tires, and thus use less Tyrfil material to save weight, while still having 130mm of puncture proof sidewall.



DETECTOR
I have three detectors
- GPX4500
- GP3500 (plan on using this one) with Detac Amplifier, rigging it up to speakers in my car for surround sound detecting.
- SD2000

COIL
- Coiltek 40' x 20" Drag Coil Anti-interference


DRAG MAT
I have two 5 meter long pieces of Insertion Rubber (conveyor belt)
- One is 3mm thick x 1200mm wide (weighs 27kg)
- One is 6mm x 1200mm wide (weighs 55kg)
I think the 6mm will last much better being dragged around all day, however it's very heavy and I can't lift it easily. I have an existing drag coil frame that is made from 10mm poly plastic that I can bond to the rubber mat with some sort of Contact adhesive like selleys quick grip.

The end of the mat near the car will be clamped between two 1200mm wide bars of steel and this will be fastened to my tow bar by sliding it onto a 150mm high steel bolt... this enables side to side motion of the mat only meaning that this end of the mat is stabilized horizontally at all times to encourage the rubber mat to track over obstacles smoothly with minimal disruption to the coil. Obviously the coil will rise with vegetation and then fall again when there is none, but this system should give a smooth consistent ride to the drag coil. Using this mat system will enable me to drag over low vegetation, the coil seems to pick up decent sized nuggets at about 30-60cm.  


If you have any tips on what tire width is best to use (skinny or fat), or if you have tips on making/using drag coils  that would be appreciated. I am going to use a Garmin GPSMAP 64 GPS with Satellite imagery to navigate & track my dragging. I plan on putting my detector control box in a protected, metal lined box around 2 meters back from the car mounted to the mat, and then the coil 2.5 meters behind that. I may also use a spray marker system to mark targets but have not worked out how to do that yet.

I figure that using this drag coil I can cover hundred of times the ground in total comfort. Screw the small stuff I say.

Hi BigAl.

I have all the information about this subject that you seek.

Al I have sent you a Personal Message.

cheers ozgold.

PS just click on the PM box or on my name here.

Hi Al, welcome to the forum.

These are my opinions only.

Firstly, forget the Jeep.
Any break downs out here (and with a jeep it will probably break down) and unless you're a Jeep mechanic yourself, any local mechanic will scratch his head and laugh at you or charge you more than the replacement cost of a new Jeep to fix it.
Plus do they come in diesel?

You can fix anything on a Toyota with fence wire, cable ties and a pair of your wife's old panty hose. Failing that, you can nick one when the drillers aren't looking and raid it for parts.

Forget the 3 inch lift.
While it may look cool, If you need a 3 inch lift it's way way too rough for a drag coil.

Forget the you beaut tyres.
Just get and learn to change spilt rims. Skinnies are the go.
Failing that, regular tyres and a bung kit. A stake in the side wall of a tubeless tyre though, is most times more than a bung can handle. 
With a side wall puncture in a tubed tyre you can often patch the tube, sleeve it and put an internal patch in the tyre to get you out of trouble.
I did 3 tyres the other day and only had 2 spares. But I removed, split, patched, put back together, pumped and refitted out in the bush in under half an hour.

Just stay out of the mud. No matter what tyre you're wearing, diff lockers or not, most times you're not going anywhere anyway.
Plus lease holders out here will shoot you if they catch you driving about in the mud.  Are these your leases you're planning on hitting? Salt lakes?

A quad will tow your coil and it will tow it a hell of a lot more places than a vehicle will. 99% of quad will also have more than enough ground clearance.

Finally, when you've had your fill of the big gold, feel free to give me a hoy as I sure don't mind the small stuff.

Cheers,

Steve

Yes, i agree with mad tuna.
the conveyer belting that you want to use, check it to see if it has steel wire in it as some of the belting your detector will pick up.
i thought by reading what you want to do was go out in the middle of summer and raid leases - only saying that as you need air conditioning     just ribbing you.   
When we set up the 20 x 40 coil we had we dragged it on a large sheet of coreflute  and had the detector on another sheet in front of that with the coil sheet on top of the first sheet at its leading front edge so it did not dig in. The detector was secured on an old lounge cushion and then had an extension lead for the ear phones so the coil and control box was about 25foot behind the quad bike. That stopped any ignition noise.
to stop the front coreflute digging into the ground we had a set of sacktruck wheels on a longer axle at the front to hold it up off the ground. We worked out that it worked much better with only very low air pressure in the tyres so they did not bounce at all when they hit rocks. We also used high pressure water poly pipe to hold it together. Worked a real treat.  The quad was good in the fact it had high / low range so could travel slowly.
good luck in your setup. TG

I love the idea of riding/driving around detecting but what happened to the rules about "hand held" non mechanical detecting????? There's a heap of people doing the "drag" thing but I'm afraid it's outside the DMP regs I reckon. It's along the lines of a mini mag survey and I'd imagine you'd at least have to have an EL to do it.
Having said that, you may have the tenements to do just that, can't tell from your post.
Tuna's advice is very sound, skinnies on splits have proved the go in the bush and never go detecting in the mud.
cheers
Brett

mulgadansa wrote:I love the idea of riding/driving around detecting but what happened to the rules about "hand held" non mechanical detecting????? There's a heap of people doing the "drag" thing but I'm afraid it's outside the DMP regs I reckon. It's along the lines of a mini mag survey and I'd imagine you'd at least have to have an EL to do it.
Having said that, you may have the tenements to do just that, can't tell from your post.
Tuna's advice is very sound, skinnies on splits have proved the go in the bush and never go detecting in the mud.
cheers
Brett

My understanding is that the 'hand tools only' restrictions only apply to the extraction of minerals from the ground. Riding around on a quad bike detecting is not extracting minerals from the ground, and therefore is permitted under regulations. Just make sure you use hand tools only on the actual dig.  I could be wrong, this is just my understanding.

This is also why I believe it's ok for me to use my powered highbanker to process minerals (it uses a petrol water pump). I am not using it to extract the minerals though, I am using a shovel for that. I am only using it to process the minerals which is what i believe makes it ok. This is what I plan on arguing in court anyway