'volpe,' my reply is tardy as I got sidetracked with a phone call regarding metal detecting and, trust me, I can get involved with some discussions on various topics related to this great sport. I hope you read the reply by 'Kapok' as it was correct and based on his 40 years of metal detecting since Scott got started back in 1977 and if anyone puts in the time and effort to get involved in detecting they are sure to learn more about the whys and why-nots, hows and how-tos, and thankfully share their experiences with others.
I'm a pretty Avid Detectorist myself, and have been since March of '65 so I'll just add my comments to support Scott's response.
volpe said:
I have a R2 and am detecting an 1873 home and have found horse shoes and nails among other things. The horseshoe nails show up at 96 VDI, yes the numbers vary, but 96 is predominate, especially as I wiggle the coil over the target.
First, let me congratulate you for selecting the Makro Racer 2 as it is one of the better general-purpose detectors on the market today. I'll also envy the fact that you are detecting an 1873 home as that hints to the opportunity that you have a good chance of finding older dated coins and other early era artifacts of interest ... and it also means you are likely to have to deal with more accumulated trash lost of discarded trash.
There will be some learning needed to get to know the Racer 2's behavior afield and the various adjustment features it offers. Let me insert here this statement: There is no such thing as a 'perfect' metal detector, nor 'perfect' audio or visual Target ID response as there are just too many variables to deal with. It will also be the detector operator's responsibility to select the best size and type of search coil, detector settings, and sweep technique to get the best results possible based upon the search site condition and challenges.
One example are the horseshoe nails you are finding, and the ± '96' VDI numeric response you get, especially when you 'wiggle' the search coil over those targets. Most nails, but not all nails, are made 'predominantly' out of iron, a ferrous or magnetic-based metal. Often targets we find are not 100% one specific metal type, but a blend or alloy mix of more than one metal. Those, TID responses, both visual and audible, can be inconsistent.
Then we have to deal with them being 'man-handled' from their original metal ore. Generally, pure iron would produce a lower iron audio tone and non-ferrous objects would alert us with a higher-pitched audio complemented by a higher numeric VDI response. Then along came man who tinkers with a metal, such as iron, and processes it and shapes it into an irregular form which, sometimes, also enhances the objects conductivity level which, in turn, gives us an inconsistent and often perplexing response. If iron horseshoe nails are the culprit then we have to understand why the higher TID response as well as listen closely to the audio and try to catch some tell-tale signs of an iron target response.
Oh, and about the 'wiggle' technique. It can, at times, be helpful and I often 'wiggle' a coil over a located target, but I take into consideration the size of the search coil used, the design type of coil used, the search mode and settings and the size of the 'wiggle.' That audio info is quickly considered along with the natural search sweep response that caught me attention in the first place and from that combined audio and visual response I can reasonably 'guesstimate' about the target's likely metal composition.
On most nails you have to consider the alloy make-up of the object; the size of the object, such as length and thickness; the shape such as flattened, on edge or a canted angle, opposing angles such as the body of the nail and the head of the nail, as well as if it is straight or bent at an abrupt angle. Man shapes these objects in a 'normal' fashion that can create irregular responses, and we can alter them as well such as bending them which can throw an anticipated VDI response off from 'normal.'
volpe said:
The detector is set at 2 tone, gain, 60, ID filter, 10, as well as notch filter. Iron audio, 3 tone break at 20, audio tone at 40.
Here are my Racer 2 basic settings which, in the Di2 or Two-Tone search mode, are saved as:
Gain = '95' [size=small]
(I prefer to start at a higher Gain level then reduce it, if necessary, to deal with chatter or unsteady behavior)[/size]
ID Filter = '03' [size=small]
(which I keep lower so that I can hear the presence or iron nails)[/size]
Tone Break = '10' [size=small]
(which is the Ferrous/Non-Ferrous break point)[/size]
Audio Tone = '50' for the higher, Non-Ferrous Tone
volpe said:
Secondly, Why doesn't each target give a steady tone?
By 'steady tone' I take that to mean a more consistent or tighter audio, as well as visual, response? There are several reasons, but the two primary reasons are usually because the object is not a uniform roundish-shaped metal object in a flat-to-the-coil orientation, but instead an elongated nail with an uneven shape [size=small]
(fatter head of the nail and some nail heads at more of a 90° angle to the shaft or body of the nail)[/size]. It can also be at an abrupt or angled orientation to the coil. The second reason is that you are using a Double-D designed search coil and there will be more inconsistency from the overlapped and opposing presentation of the Transmit and Receive windings as you sweep over and across the located target. There are other potential causes but those are the mail two reasons.
volpe said:
A nail is a nail, a pull tab is a pull tab, these numbers jump around as well. Yet, the R2 will ring out on coins, copper, silver etc, and of course, bottle tops.
Yes, a target-is-a-target, but there are other variables to consider. Most nails are made of iron based metals. Ferrous or magnetic in nature. They can be in a wide range of sizes and shapes and orientations to the coil. Pull tabs, to include both the older ring-pull type and the modern rectangular pry-tab design, are also made of a mix of metal alloys, generally of higher-conductive non-ferrous metals, and they are also made in odd shapes rather than a round and consistent shape.
Back in June of '94 I was preparing to give a presentation on Recreational Metal Detecting at a week-long class and went to a local city park to search up all the possible 'pull tabs' I could find. That included complete and flat-shaped older ring-pull tabs, ring-pull types with the 'beaver tail' bent over the ring portion, the 'beaver tail' bent through or curled into the ring portion, separate beaver tail pieces and separated ring portions, and quite a few of the newer style rectangular-shaped pry-tabs. I used a White's 5900 Di Pro SL detector and tested each of those samples, then numbered them in order of the visual numeric TID response they produced as the needle meter accurately settled on the most consistent response.
There were '27' different conductivity groups once I worked them out to have one TID response for each specimen. Twenty-seven different TID readings from one 'class' of targets .. "pull tabs" ... and that was using a round, Concentric coil that would provide me the most consistent audio and visual response from a sampled target. That made them range from just below the conductivity and TID of a US 5¢ 'nickel' coin and on up above to include most of the older pull-tab readings.
Bottle caps are another problem target we deal with. Most are made of a ferrous-based metal that used to 'read' with or produce a negative rejected response since they are an iron, nickel or some type of magnetic metal. But, again, man formed them into a shape that enhances their conductivity and with today's 'modern' circuitry designs they can usually produce an up-scale response with a visual TID that, while often more radical or jumpy, seems to fall in the 1¢/10¢25¢ TID range. This can occur with most any modern detector and search coil, but classifying an iron/ferrous/magnetic type metal is also usually more difficult with a Double-D search coil, and augmented when it is a larger-size DD coil rather than a smaller coil size.
Most coins, referring here to USA coinage that is almost all based on non-ferrous, higher-conductive metals and formed into a round shape, are going to provide a more consistent numeric VDI response thanks to their more consistent shape, size and alloy content. Even cons, however, can, and will, respond with a TID that might be 'spot-on' accurate or perhaps read a little lower than normal, or higher than normal, based upon their depth in the ground, the position or orientation to the coil,
volpe said:
this is my first detector and have 40-50 hours with it.
I used to put in 40-50 hours a week when I got started in the hobby, but that was long before we had Discrimination, Auto-Tune, Ground Balance, and other 'modern' additions like Audio Tone ID or any visual Target ID. It was 9 years before we had Ground Balance circuitry on our hobby-based detectors, and 18 years before Target ID, as a matter-of-fact, so I was fortunate to get a lot of field time and learning time along the way as we progressed to today.
As a beginner, just starting out today with a new Makro Racer 2 that has so many advanced features and performance, you have a lot more to learn about the 'basics' of how detectors work [size=small]
(or are supposed to work under ideal conditions)[/size] and a lot to learn about just what the different functions and features are that the Racer 2 provides. It is going to take time, and patience, and just kind of take it one step at a time so that you know how and why the different adjustments work and how they can help you in your searches.
Also, you didn't mention which search coil you were using in your post, or which search coils you currently have for the Racer 2. Also, other than hunting the 1800's house site, what type of detecting do you plan to do? Coin & Jewelry Hunt in urban environments? Relic Hunt older sites that are more out-of-the-way? Maybe a little Beach Hunting, fresh or salt water environments?
Each type of hunt site you pick might be better worked with a different search mode, such as using Di3/Three-Tone and a smaller-size coil when working a very nail infested, dense iron debris old site that has a lot of rusty tin shards, since the processed Three-Tone performance works well at audibly classifying a lot of the rusty tin. Learning to use a very functional slow and methodical sweep speed would be in your favor, too, so you don't miss targets by using a faster sweep speed and less efficient site coverage. It's all a learning game and, trust me, the game is never ending. There's no perfect detector, and there is no detectorist who "knows it all" either. It's always a matter of learning to better understand the ways and hows and whys to enhance your personal knowledge and skill level.
It will come in time, and you're going to do well along the way by having an excellent detector in-hand as you do. If you don't have a smaller-size coil I will suggest getting one, and using it often. Tighter TID read-outs, less interference from adjacent trash, lighter and more comfortable balance. Use the standard 7X11 DD for more open area with fewer trash targets, if that's the only coil you have.
Monte