Tracing cast iron pipe?

[parkgt]

A friend has asked me to try to trace a 6" cast iron pipe from his house out to a un-located septic tank. It appears that this pipe could be as much as 36" below ground.

Is the 11" coil likely to be able to trace it and what settings would be suggested? I have been trying to reject this type of material not find it!

 

[trojdor]

Having done this before, I would suggest that you'll have better luck locating the lid/cap to the septic tank...
It's big metal, and won't be too far below the surface.

Just go all metal and listen to the size of the target...ignore the display...you'll know when you've found it.
(You don't need much sensitivity for this task...you're basically looking for a target not much smaller than a manhole cover, just a few inches down.)

mike

 

[parkgt]

Thanks for the reply. What exactly do you mean by all metal? No disc and no notch? What freq?

 

[trojdor]

Thanks for the reply. What exactly do you mean by all metal? No disc and no notch? What freq?

I was referring to any mode that is all metal...such as the Goldfield program, or my preference...the Non-motion all-metal mode (see page 21 in your manual for specifics)
Make sure you ground balance properly.
As far as freqs and sens...don't overthink it. Just use the default. Back off the sens, if you need to...you'll be looking for a giant metal lid that virtually any metal detector ever made could easily find.

You're basically trying to do exactly the opposite of what you normally do...which is to ignore iron while going deep for multiple small targets.
Now you're going to try to find a single large, iron, shallow target.

good luck,
mike

 

[parkgt]

Thanks Mike, I will give it a try.

 

[Gary-B]

Or try program 10 Goldfield, if your searching for a large lid keep the search coil at waist height to eliminate sounds from small iron.

Good luck

 

[Arthur-Canada]

Rent yourself a magnetic locator. That's what they are designed to do. They only react to iron targets and not bits of aluminum and coins. You can rent them at Home Depot or outfits that rent construction equipment. If you know a local land surveyor you might be able to borrow theirs. They all have them to locate boundary corners

 

[CO_T\Huntr]

I witched mine and was totally impressed that it was spot on
but this was before I was a detecting nut... just saying!
I just used 2 bare metal ell shaped welding rods, it was scary accurate!
And it was 5-6'

 

[detectin4fun]

If you have a basement look for where the black sewage pipe exits the basement wall. Where the clean out is inside is where the main line is located. The septic line likely goes straight out and into the septic tank. The septic field is beyond the tank. My parents old septic tank lid was a concrete lid that was very much like a patio paver with not metal inside. Detector or magnetic device would not find the lid. The lid should be a little below the sod with a small layer of dirt. Dry weather will revel the septic tank lid at times due to the lack of soil depth and it drying out first during drought conditions. Try a ground rod or rebar rod and drive The probe into the ground you will hear the hollow thud when you hit the cover. It is not that deep.
The new owner of the house called me one night late complaining the septic tank guy was there charging him by the hour for searching because he could not find the tank lid. The guy didn't use a gun to rob him that night. When you find the lid mark the clean out inside the house with instructions so the next searcher has an idea where the tank lid is located. Good luck with your search.

 

[markg]

No need to trace the pipe. I've found several well caps and sewer tanks with this technique. See what direction the sewer leaves the home. Walk at least 25 feet from house. Turn on the XP Deus and reduce the discrimination to 0, or get adventurous by using the gold field program and look for a very large target. In most cases, even if the tank is 2' deep you will get either a large or overload signal that is several feet wide. Make it fun. Before detectors I used a small metal rod with a point and T handle to probe for the tank. A lot harder than using a detector.