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Slug fence

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camerart

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Hi,

Last year, in order to keep the slugs and snails from getting to my vegetables, I made a simple slug fence. It was only a metal pipe laid on the earth round the plot, with 12v connected to it, and the negative connected to an earth spike in the centre of the plot. This mainly worked ok, but not completely.

This year I have just made a 'better' one out of lengths of 1 1/2 inch wide plastic and 1/4 inch flat copper copper strips fitted about 1/8 inch apart. The 12v battery is connected pos to one and neg to the other, with a light bulb in series, in case of short circuit.

Cheers, Camerart.

[EDITED, after IDEAS and SUGGESTIONS up to last date] [With added cat repellent]

It should be able to be left alone (2 weeks holiday) without chasing slugs/snails with a torch and sprays, or add salt, coffee grounds, diatomaceous earth, egg shells, cat/lion/hyena pee or any other substance, simply this years circuit but improved if possible.

This years circuit is working well, the vegetables are growing, only one sign of leaf chomping so far. So only a track inspection and a (used:)) toothbrush to clear the track is needed.

PROBLEMS: I am not aiming to kill slugs/snails just turn them away, but I have to clean the tracks each morning as they are 'fried' (1-3/day) less as time goes on. I assume there is a current of app 1Amp. So if one slug 'attacks' they get the full 1amp, if 2 'attack they share. I think it would be better if less current was supplied, enough to turn them back, but if 2 arrive it would be raised to suit.

EDIT: 2015
Last years fence was a horizontal track of two 5mm tracks of copper fixed to lengths of plastic. While it worked ok, it gradually got oxidised over time. This allowed slugs/snails to get halfway across before their action cleaned off the oxidisation, then they got fried. This is not my intention, I only want them to turn back.

This year, after some thought, I made a wooden fence approx 6 inches high, with once again two tracks, but of stainless steel wrapped round the whole perimeter, approx 5mm apart. One to negative and the other to positive, in series with a light bulb, in case of shorting. Hopefully any deaths, will drop off. Last night was the first night, so I 'trained' a slug and a snail to try to cross. Neither did, so I assume it will work, and keep clean this time.

I used reclaimed wood for the fence and an old battery, with a solar charger. Plus the cost of S/S wire a few pounds, so very cheap.

Here's a photo: Not pretty but affective (I hope)

Camerart.
 

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How about a moat of beer?

In your case, you probably need to feed the gizmo an AC voltage and/or use another material besides copper or plate the copper. A possible material might be stainless screen.

keeping the copper dry might also work.
 
What a waste of beer !

As above, salt seems to work nicely for slugs.

I don't want to waste beer or salt either. I actually don't want to put any chemicals on the garden, if I can help it.

From the answers so far (Thanks) I am interested in whether an ac voltage would work, or would it also suffer from similar affects?

Cheers, Camerart.
 
How about a large ring made of copper pipe, painted or completely insulated with something. Then, take a file to the top surface and remove the paint layer for some 3 or 4mm all along its length. The idea being to have a narrow exposed copper surface facing upward, going all around the veg plot. 12V to the pipe, negative to an earth spike. Should work better since current can't leak away to ground so easily, even if it gets rained on. Just an idea!

If you do manage to come up with something that works, please let us know.
 
How about a large ring made of copper pipe, painted or completely insulated with something. Then, take a file to the top surface and remove the paint layer for some 3 or 4mm all along its length. The idea being to have a narrow exposed copper surface facing upward, going all around the veg plot. 12V to the pipe, negative to an earth spike. Should work better since current can't leak away to ground so easily, even if it gets rained on. Just an idea!

This was a bit like the original last year, the earth spike was the weakest part especially wet/dry conditions. If I can get this years one to work, (after spending some time on it already) I would prefer it. I'm using all reclaimed bits.

So far a 'roof' or AC, if this would make it work when wet are the best.

Cheers, Camerart.
 
Don't use a ground spike, you don't need (or want!) currents through metal into and through the soil.

I would make it like an electric cow fence, totally insulated from ground with repeating high energy pulses. It will still zap slugs.
 
I didnt know low voltage dc kept slugs away, my wifes a keen gardener I'll remember that one.

The problem with copper is, in the presence of dc and water you'll get electrolosys and the copper will turn to oxide which is conductive, probably why the bulb comes on.

Heres a cool electric fence design:
**broken link removed**
I built this, better not say what for however if you want to reduce the o/p, then put a car spark plug from the fence o/p to ground (batt -), then setting the plug gap controls the amount of 'clout' the fence will give, the smaller the gap the lesser.

Another way would be to buy one of these cheap tennis bat type bug zappers that seem to be popukar at the moment and raid the board out of it, they produce something like 4 or 5 kv and they are dc.
 
You probably don't need a power source with the copper, the copper should work fine on it's own, slugs won't cross it. i use copper tape on a a small herb garden. As long as it is wider than a inch a slug won't even try.
 
Don't use a ground spike, you don't need (or want!) currents through metal into and through the soil.

I would make it like an electric cow fence, totally insulated from ground with repeating high energy pulses. It will still zap slugs.

Ok about the ground spike, that was so last year:)

If I can't get this problem solved, next year I'll make a cow fence. I've seen 'field' electric fences where the wire was touching all sorts of foliage, and still stung, so this might work in the rain if the plastic got soaked.

Cheers, Camerart.
 
I didnt know low voltage dc kept slugs away, my wifes a keen gardener I'll remember that one.

The problem with copper is, in the presence of dc and water you'll get electrolosys and the copper will turn to oxide which is conductive, probably why the bulb comes on.

Heres a cool electric fence design:
**broken link removed**
I built this, better not say what for however if you want to reduce the o/p, then put a car spark plug from the fence o/p to ground (batt -), then setting the plug gap controls the amount of 'clout' the fence will give, the smaller the gap the lesser.

Another way would be to buy one of these cheap tennis bat type bug zappers that seem to be popukar at the moment and raid the board out of it, they produce something like 4 or 5 kv and they are dc.

12v volts gives quite a fast response if a slug tries to cross it, have you ever tested a 9v cell with your tongue?

MR RB said not to put voltages through the ground. I'm sure there is a scientific explanation, perhaps effects the chemistry in the soil, or effects worms, but I agree, it probably isn't the best thing to do, so I'' try to avoid it from now on. ELECTRIC fence goes down the list.

You explain that DC causes electrolysis, but will AC that Keepitsimplestupid suggested.
 
You probably don't need a power source with the copper, the copper should work fine on it's own, slugs won't cross it. i use copper tape on a a small herb garden. As long as it is wider than a inch a slug won't even try.

Last year I make a 'coral' with copper and placed slugs and snails inside to see if they could escape, they did, but didn't after I added 12V and spike.

Cheers, Camerart.
 
Today I fitted an AC transformer 12V 1A. I first checked the track, and had to clean off baby petrified slugs (And I don't mean scared) it seems the voltage is too high for them to turn back like the bigger ones do. I sprayed the track and the voltage went down to 2V, but there isn't a sign of green/reaction.

I wonder if a higher current will keep the voltage steady. Perhaps a lower voltage would still work with young and old, as long as it stayed constant when wet.

A note: Soil, and as I mentioned, slugs might need cleaning off the tracks, so an idea I had to invert it all onto a vertical 4 inch fence won't work as it would be difficult to clean.

Cheers, Camerart.
 
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AC in laymans terms doesnt cause electrolosys, actually the effects caused on the positive cycle are reversed on the negative, so very little effects occur.

Good to see you have it sorted.

I dont think 12v dc would cause much harm with a ground electrode, allthough ac subtstations and manufacturing plants shove several amps into the ground, that'd be a no no if the effects were bad.

And now you mention it I spose testing a 9v battery by licking it wouldnt be too nice for a slug, esp with 12v, I had bad problems with slugs at my old address, so far with the first spring in my new home I havent seen any, but if I do I know what to do.
 
AC in laymans terms doesnt cause electrolosys, actually the effects caused on the positive cycle are reversed on the negative, so very little effects occur.

Good to see you have it sorted.

I dont think 12v dc would cause much harm with a ground electrode, allthough ac subtstations and manufacturing plants shove several amps into the ground, that'd be a no no if the effects were bad.

And now you mention it I spose testing a 9v battery by licking it wouldnt be too nice for a slug, esp with 12v, I had bad problems with slugs at my old address, so far with the first spring in my new home I haven't seen any, but if I do I know what to do.

I wouldn't say it was sorted out yet, but yesterday I changed back to 12V dc (large battery) because of the wet voltage drop and added a canopy along around the perimeter. Today I cleared a couple of baby slugs off, and now wait for rain, to see what happens.

I have left the ground spike idea behind, because it requires a shortish gap between positive and the soil, or else smaller slugs can get over it. Also the varying effects of wet and dry soil.

I think two tracks 1/4 inch apart on a vertical surface about 4 inches up, with probably 6-12V ? and 3-5 Amps ? will be what I aim for next time.

Cheers, Camerart.
 
You can buy a copper tape slug barrier to put round plant pots - no power needed. For a stronger effect again with no power needed, you could have parallel fences of copper and some other metal - any slug trying to cross it would become an electrolyte.

They supposedly don't like to cross smashed up eggshells, but I don't know what depth or width you'd need. Also gives your plants a bit of a feed.
 
You can buy a copper tape slug barrier to put round plant pots - no power needed. For a stronger effect again with no power needed, you could have parallel fences of copper and some other metal - any slug trying to cross it would become an electrolyte.

They supposedly don't like to cross smashed up eggshells, but I don't know what depth or width you'd need. Also gives your plants a bit of a feed.

As I said earlier, I tried making a Corral out of copper with slugs and snails inside it. some escaped, that's why I upped the voltage.

I don't eat enough eggs for shells:)

I didn't try the two different metals, this is worth consideration, but I'm happy with the 12v volts, it's no effort at all, and the copper is substantial, so I hope it will last.

Cheers, Camerart.
 
Now you see if it was me I'd have to overcomplicate the whole thing with a microcontroller and generate ac as well as detecting if there was a current draw to see if anything was on the electrodes.

I tried slug shingle, an equivalent to eggshells, didnt work, if anything I had more of the critters.

Anyone know a way of doing something the opposite, I want bee's to polinate the plants in my greenhouse, but for some reason at my new address they dont want to go in.
 
Hi,

Not really a circuit, but can anyone help with a little problem?

Last year, in order to keep the slugs and snails from getting to my vegetables, I made a simple slug fence. It was only a metal pipe laid on the earth round the plot, with 12v connected to it, and the negative connected to an earth spike in the centre of the plot. This mainly worked ok, but not completely.

This year I have just made a 'better' one out of lengths of 1 1/2 inch wide plastic and 1/4 inch flat copper copper strips fitted about 1/8 inch apart. The 12v battery is connected pos to one and neg to the other, with a light bulb in series, in case of short circuit.

I added plants and watered them. All was fine for a few hours, till I noticed the bulb was on. What happened was the water had turned green in places, and the chemical reaction was shorting it out. I understand the reason why, but can anyone think of a simple solution, or do I need to build a mini roof to keep the copper dry?

Cheers, Camerart.

We just use salt..... It seems to be the best wall for slugs..

I wouldn't use salt, personally. It can destroy the soil and make it unusable for growing things.

I have had the same problem with slugs, and I have a slightly less-technical solution (guess that's just the gardener in me). I use something called diatomaceous earth. It's basically ground-up sharp rock that comes from fossilized remains of diatoms (algae). It is an odorless powder that you can sprinkle around your plants. Since it's calcium, it actually helps the plants grow, but the microscopic razor-sharp pieces will seriously hurt any insects crawling along the ground. It is a good way to keep them out of your garden, and I highly recommend it.

My $0.02 :)

Good luck!
Matt
 
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