Coil upgrade

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Simonrocco12
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Coil upgrade

Post by Simonrocco12 » Sat Jun 10, 2017 3:29 pm

Iv got a garrett ace 300i with the standard 7"x10" inch coil on I'm thinking about upgrading to a slightly bigger one like a 8.5"x11" but I'd like a bit of advice first would it give me more depth and coverage than the standard coil and would it mask any targets that the smaller coil wouldn't any help would be greatly appreciated thanks sr



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Re: Coil upgrade

Post by Koala » Sat Jun 10, 2017 4:53 pm

Not my machine but I have various coils from 5 1/2" concentric to 12"x12" DD

A general answer is yes to both questions.


I see you have only had you machine a couple of months. There is always a feeling a bigger coil will find more. This is rarely the case.


Is it worth the extra weight. Probably not.


If you are doing 50% overlap swings not that anyone does. You can move forward an extra 1/2"


You gain a small amount depth on larger size targets. But loose with more targets under the coil.


In summery. On quite fields you will gain a bit. On noisy fields you will loose a bit. In reality its going to be very close to one you already have.

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Re: Coil upgrade

Post by Simonrocco12 » Sat Jun 10, 2017 5:15 pm

The reason I'm thinking about a slightly bigger coil is i was out yesterday and I found a coin at between 15-20cm deep and I went back over the hole and sod and soil before I filled the hole back in and I got no more signals then about ten mins later my friend went over the same hole and got another coin but it was slightly deeper than my machine would pick up

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Re: Coil upgrade

Post by Koala » Sat Jun 10, 2017 6:37 pm

What was the machine he was using
What metal was the coin made of

Swinging in different direction east west vs north south can make a difference
Near by iron?
Discrimination level?
Sweep speed?

So many variables. Its impossible to tell.

You could try re burying it and compare between yours and your friends machines.

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Re: Coil upgrade

Post by Simonrocco12 » Sat Jun 10, 2017 7:05 pm

My friend was using an at pro with standard coil and he was facing the same direction that I was he was using it in standard mode with iron discrimination at 35 it was an old vicky penny same as the one I found I don't know which way it was lying in the hole though I think I might just have to buy one and see how it goes thanks for your help

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Re: Coil upgrade

Post by Koala » Sat Jun 10, 2017 8:11 pm

Not a fair comparison as you can ground balance the AT Pro

Vicky penny I would class as a large target so yes there would be a difference between the coils you mention.

Once you get down to 1/2 penny size the difference will be negligible.

Tiny silver half pennies especially on there edge the small coil will do better.

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Re: Coil upgrade

Post by Simonrocco12 » Sun Jun 11, 2017 10:55 am

Thanks for your help I will be getting an at pro myself eventually but it won't be for a couple of years yet so I think in the mean time I'll invest in a slightly bigger coil and see how I get on with it but thanks again for your help all the best Sr

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Re: Coil upgrade

Post by Saffron » Sun Jun 11, 2017 11:45 am

Basically all coils have strong points and weaker points. The standard coil is what the manufactur considers to be the best compromise to provide a good allrounder. As a general rule a larger coil gives more depth but you lose sensitivity to smaller targets and in seperation between targets (so iron is more likely to mask a good target); although this relates to Nel coils the results for the same size coils by other manufacturers would be about the same http://nel-coils.com/index.php/en/

By changing coils you will also gain a bit of extra weight, which you probably will not notice, but it will change the balance of the machine which you might.

The example you gave of where you missed a coin in the hole with the 300i and your friend detected it with the AT Pro, is a good comparison of the two machines ... but it is NOT a fair comparison of the coils. With both being Garretts the coils might be interchangable (I have not checked), if you switched coils and did a test that would be a fair and much better comparison.

For the record I had the Ace 250 and got a Nel Tornado coil, purely for better ground coverage as my ground had few good targets and limited iron (so less chance of masking than on some permissions). The improved ground coverage was an advantage and it might have punched slightly deeper but the change in balance was very noticable and the machine was not so easy to use for a long session, it also failed to cope with wet sand on a beach where the standard coil had.

Evan

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Re: Coil upgrade

Post by Simonrocco12 » Mon Jun 12, 2017 1:47 pm

Thanks for your reply the connectors on the coils on the at pro are different to the 300I I think it's because the at pro is waterproof so I can't try the bigger coil on my machine I think it's just going to be a case of buy it and try it and see and learn by trial and error thanks for the info

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