Compass Depth Doubler

[Artyom]

ivconic, you will have to send you a perforator for the successful introduction of electrodes and a successful search for coins))))

[Skippy]

An alternative helper system:
If you drill a 4.4mm hole through your rod ( as you previously described ) and tap it with an M5 thread [ or similar with M6 ]. Then screw in a length of steel M5-threaded rod, so it protrudes 15mm each side of the rod. Some epoxy resin will hold it in place. Then you will have no problem with the hole closing up due to hammering. If you intentionally cut a slightly incomplete tap, the threaded rod will be tight, and may need no bonding. To apply torque when inserting the rod, put two M5 nuts on the end of the rod and 'lock' them together. Use the nut to screw in the rod, then un-lock the two nuts and remove when done.

[ivconic]

[ivconic]

[ivconic]

Previous post, that "helper" should be very strong, to withstand all the force of turning and pulling.
I put it 5mm for it... kinda doubt it can be made to whitstand too much force, I am not happy.

[ivconic]

[ivconic]

[ivconic]

This looks like it can whitstand the force of "unscrewing" and pulling.
I think I am happy with this.

[Skippy]

Regarding the previous drawing : The U - shaped cutouts in the special tool should go at 90 degrees to how you have drawn them, or at least at 45 degrees. That way, the two pegs on the probe rod will sit in the bottom of the U when you apply force.
I see you have drawn some blue sleeve over the pegs. I was going to add to my previous post that I thought a length of heatshrink sleeving over the pegs would be a good idea, to cover the dangerous metal edges. Make sure the heatshrink goes past the end of the peg, and shrinks around it.

Another alternative: use two hexagon head bolts screwed in from opposite sides of the probe. Example M5 x 16mm. The bolt goes in 7.5mm, leaving 9mm of space for a tool. And the 'tool' need only be a length of rope, 4mm diameter, tied in a loop ... lightweight and simple. Allen headed bolts would look prettier:
https://www.ebay.co.uk/itm/121633184230

[ivconic]

This is actually a screw and two nuts. I drew them quickly because it was easier for me.
According to width... 4 nuts actually.

[ivconic]

Regarding the previous drawing : The U - shaped cutouts in the special tool should go at 90 degrees to how you have drawn them, or at least at 45 degrees. That way, the two pegs on the probe rod will sit in the bottom of the U when you apply force...

I don't think there's any need.
The idea is to pull the tool from above and screw or unscrew it.
Because it can happen that the soil immediately around the rod is inconsistent.
If I apply the "leverage" principle, the metal tool will simply sink into the soil.
If they are 90 degrees in relation to the current state; I'm losing the ability to pull up...
If I understood you correctly?

[Skippy]

No, you are misinderstanding. Sadly I cannot add image attachments with the new Vbulletin software, so ... in words:
When pulling the extractor tool upwards, the U-slots need to be like a U, not like a C. Or like a tilted U, at 45 degrees.
----
If you think rotation of the probe could be a useful method to aid removal, you should consider square-section rods, and maybe hexagonal-section, too. If these are rotated, they will push out the dirt a little, making a small space, and easing removal. Rotating a round rod will clearly do little.

[ivconic]

Ok, let's see if I understood you correctly; The "cuts" are more like a "U" rather than a "C", I thought of that.

[ivconic]

One of the variants can be at an angle of 45 degrees, ok why not.

[ivconic]

Designing on "paper" is always the easier part of the job.
Without advanced "machining" and with the help of only handy amateur tools... this will not be an easy job at all.