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switch
07-27-2011, 08:09 AM
where is the center of a coil...how do you know where it is hitting...

I mean I have dug plugs and was dead on...but I still end up digging a hole right next to an item or have to dig three holes in the same area just to find something some times....how do you tell? :dontknow:

RobW
07-27-2011, 08:12 AM
It all depends on the detector unit itself and more specifically the coil.

What are you swinging?

Duh...an Ace 350....I have not used one of these though I did buy one for my dad for x-mas...and he's used it once to my knowledge to find a part off his mower 8/

My last experince with a Garrett, was with the 1350. I found that in pinpoint mode, it would litterally be at the tip of the coil, in the U part of the coil. It would pin point on a dime lol

switch
07-27-2011, 08:14 AM
It all depends on the detector unit itself and more specifically the coil.

What are you swinging?


I am using a Garrett Ace 350 with its default coil, a DD.

RobW
07-27-2011, 08:17 AM
you responded before I finished my modification

switch
07-27-2011, 08:24 AM
you responded before I finished my modification


And you responded right before I updated my signature. lol

I was wondering what to do not using pinpoint, although perhaps I should...I just can't seem to get the knack of that either... it seems like everything is a target. lol

Lowjiber
07-27-2011, 10:09 AM
Here are my thoughts...

Concentric coils tend to be more accurate when pinpointing than DD's. From a manufacturing perspective, it is much easier to align the centers of the individual (Transmit and Recieve) loops about the common axis of a concentric coil. A DD coil on the other hand depends upon the relative placement of the two loops beside each other with a slight overlap on the straight sides of each.

While loops are machine wound (therefore more identical) and the positioning is more-or-less standardized by the coil encasement, the precision required to allow your VLF detector to measure the phase shift exactly in the center is beyond economical assembly techniques. Suffice to say that the center of the pinpoint of any coil is usually pretty close to the center of the coil's frame. For most folks, that is satisfactory and a deviation of half an inch or so is not a big deal.

I have several detectors and God knows how many coils...each with a slightly different pinpointing sweet spot. I suggest practicing with a gold ear ring lying in the grass to determine where that spot is relative to your particular coil.

If you're digging holes beside your target, there is likely more of a technique problem than a centering issue. I suggest pinpointing from two directions (90 degrees from each other) to determine the location...this is especially handy with a DD coil. While it may seem obvious, keep the coil level as you sweep across a target.

RobW
07-27-2011, 10:57 AM
And you responded right before I updated my signature. lol

I was wondering what to do not using pinpoint, although perhaps I should...I just can't seem to get the knack of that either... it seems like everything is a target. lol


You HAVE to pinpoint. Otherwise you just get a general sense......and end up digging numerous holes......like you are.

You will find that you then have more time to detect, thus resulting in more finds, thus resulting in better finds....it's all in the numbers :yes:

Lowjiber is correct. Put an object down and practice pin pointing on it to find that sweet spot that correlates to the coil. I would reccomend a smal object like a dime. Do it many times.

switch
07-27-2011, 11:19 AM
OH OH I see. lol I didn't realize the pinpoint function was actually a standard device, and thought that I should be able to just use the detector and not worry about that. I thought it was a convenience. I will practice my pinpointing. thumbsup01

Thanks everybody!

coinnut
07-27-2011, 08:55 PM
Pinpointing is crucial, and I'm bad at it lol That is why I dig big holes in the woods :yes:

switch
07-27-2011, 09:00 PM
Pinpointing is crucial, and I'm bad at it lol That is why I dig big holes in the woods :yes:


For a while I was thinking backhoe. :thinkingabout:

LOL lol

aloldstuff
08-06-2011, 07:21 AM
On my Prizm IV I have found that sometimes the target is dead center and if it is not then I have learned that the target will be northwest of the center. Learned this by digging about a thousand targets. On the V3i it is pretty much at the top of my center.

Mudder
08-07-2011, 04:08 PM
The pinpoint function will be your best friend, but you will have to practice a lot to get the skill set that you need with this function. I was terrible to start, and I took a lot of suggestions and put them to work for me. First, place a coin or whatever will give you a good signal in the grass and using the pin pointer find your highest signal. Do this until you really get good at it, and at the same time see where the object is in relation to your coil. On my Ace 250 it is at the very top of the coil on the inside curve, but on your double D it may be in a different spot. I even went so far as to mark the spot with a silver sharpie, just as a reminder in the heat of the moment. Now the practice, I took several pieces of card board and taped pennies to the bottom in different spots. Then using the pin pointer, I searched for the coin until I think it is in the sweet spot. I then use a coin probe to poke through the card board to see if I'm on target. This method works well and I normally dig a small hole now, and hit the target about 95% of the time.

switch
08-07-2011, 04:11 PM
What I have been doing now is pinpointing to the highest signal - meaning middle of coil and then pulling it back until the signal vanishes, digging at the tip of the coil. So far, this seems to work. :yes:

OxShoeDrew
08-08-2011, 04:31 PM
Switch, my first MD didn't have pinpoint mode but I learned to listen and watch the depth indicator, which was very accurate. It also had very quick response....no problem. My second MD had a great PP mode..again, no problem. My third, the ace 350 has been a challenge to pp with. First, the pp mode seems to lose power as you hold the button. Your first pass over the target in pp mode will be the loudest with each successive pass getting softer. Secondly, the depth is so inaccurate as to be useless in pping. I was practing in my garden the other day and the depths were off by 6 inches at times. I can now be spot on 3 out of 4 targets but it takes a few minutes....and I still cant figure out that 4th time! I bought a sniper coil which makes pping easier but I can't use it with large tracks of land. A guy in anither forum brought thus same thing up yesterday....he is having the same issues. Disclosure, I've only had about 20 hours on the 350. I assume we'll all get better. GL and HH :groovy:

bob_e99
08-08-2011, 05:34 PM
where is the center of a coil...how do you know where it is hitting...

I mean I have dug plugs and was dead on...but I still end up digging a hole right next to an item or have to dig three holes in the same area just to find something some times....how do you tell? :dontknow:


I was having the same issue thus my manhole size plugs. I figured one huge one was better than a bunch of smaller ones clustered all together. I got a bit better with the Sovereign as time went by but still missed some targets which is very frustrating. The E-trac does a much better job and I find it's pinpointer very good which is one of the reasons that I bought it. My plugs are now a bit more reasonable.

Also, I found that if there's anything next to the target (junk or another target) I would get confused and not be able to pinpoint. Again, the E-trac has helped with that. Still learning though.

jkress
08-09-2011, 11:41 PM
Hey switch... I used the ACE 250 to dig lots of nice keepers. Once I learned to detune the pinpoint function it made a world of difference. :shocked04:

I'm assuming the 350 will work in similar.
Search at youtube for this title... Garrett Ace 250 metal detector. How to pinpoint a target

Detuning makes the process much, much more accurate.

switch
08-10-2011, 11:48 AM
Ah thanks for all the info everyone, I will take some time to go over it when I get home today. :-) Nice day to try it all out. :yes: