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Static Electricity Ground Setup.


BitchinCamaro

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My bench is made from an old prison door and has rubber wheeled casters on the legs. The stool at the bench is steel. The static buildup is noticeable, especially since Utah practically has negative relative humidity.

I've read about grounding reloading tables as a good idea , I've just never seen/considered the best way to do it. Aside from going straight ghetto by wrapping some copper wire around a table leg and jamming the other end into "mouth hole" of an electrical socket, what are the best options?

Will a concrete anchor in the floor slab act as an efficient ground, or do I have to get it as deep as a lightning ground?

Is it better to ground myself/stool to the floor, or to the grounded table? Does it matter?

Does anyone have pics of their ground setup?

part-008_zpsq8y5icoo.jpeg

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You don't need to go to earth ground, but simply lower the potential of the static discharge. Primers are extremely sensitive to very low humidity conditions, so before you drop your primers, touch the metal bench so you get rid of the static before you drop the primers. If you want to make the effort, then a true earth ground, like on your electrical box is the best way. Use a multimeter to check for low resistance. You can use the ground side of an outlet, but check with the multimeter to make sure it is a true ground. Not all outlets are grounded.

Edited by 9x45
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BitchinCamaro Don't get offended but why don't you just replace the steel bench and top with a wooden one that you can make from stock sold at a big box store and eliminate the potential issue of a primary source of spark(s) ....a potentially dangerous situation with gun powder, primers and a potential for fire where loaded ammo and these flame propagating elements are at hand. O/W you better be really sure that you don't have any cans of solvents or other flammables within a country mile that just could provide an air vapor concentration looking for a spark for ignition.

I realize that proper grounding and all that will minimize sparking but not to neutralize the main source of the issue seems risky to me in MHO. I have experienced an electrical fire that I don't want to ever experience again. It was not a pretty sight. Luckily the reload area was far distant in that event.

Regards.

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9x45, I usually do, but static general static buildup is an issue- especially with fine powders in the powder drop.

Chuckols, no offense taken.

I didn't really think that the steel top itself was a source of concern. If anything, I thought it might make it easier to lower the electrical potential.

I used to live in the Southeast too and I only felt static electricity at the beginning of a summer rainstorm or after rubbing my feet across the carpet as a kid. Now I live at 6000 feet of altitude and I have to drink a half a gallon of water by noon just to keep my nose from bleeding. When I crawl into bed at night, it looks like a mini-thunderstorm of sparks from the static discharge between the sheets and mattress. The static here is unreal.

Though I've not confirmed it, I'm pretty sure I could get a static discharge off of a wooden benchtop too. That's why I thought grounding it would be taking away the primary source of ignition.

Plus, pulling on a press bolted to a solid 400lb steel plate is just dandy :D.

Edited by BitchinCamaro
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The high-level picture of this is that you are trying to maintain equal electrical potential between everything - room, bench, floor, etc. The electronics industry has been dealing with this since the invention of the transistor. One thing to consider is to add a humidifier to your furnace. It would make the whole house more comfortable. You can add a portable to your shop but I am not sure that is best for the machine and components. I am not talking full Florida here, just getting back into double-digits. Your cat will thank you.

The important thing is to keep you and the bench at the same potential. It is a good idea to ground the bench. You can connect to the screw that holds the face plate to the electrical outlet. Unless your wiring is total hillbilly, that screw hole in the outlet is connected to the grounding wire in your house wiring. Cold water pipe is a better choice. Hot water not so much because the electrical path through the hot water heater may not be good.

A simple approach to keeping your body at the same potential is to either touch the bench first so any lightning is between your finger and the bench. If you are carrying primers over, touch the bench before you put the container on the bench. The be sure to touch the bench before you start handling them. A more positive ( :rolleyes: ) way of doing this is to get an Electrostatic Discharge (ESD) wrist strap that connects to the bench and maintains balance between the bench and your hand. You may also want to look at your floor. Carpet: BAD. But there are ESD treatments for carpets. You can get ESD waxes for hard floors or you could just get ESD mats to put by/under the bench. Google ESD wrist strap and start reading

Another aspect is safety. Ever notice that your toaster does not have a grounding plug? There is a reason for that. Since it is possible for you to be dumb and come in contact with house power by sticking something into the toaster, the industry did not want to provide a quality connection to ground for your other hand. When you look at the ESD stuff you can buy, you will notice that most of the interconnect products have a large-value resistor in series to limit the current. They still drain off static charge but do not give you a low impedance path to ground in case something bad/stupid/both happens.

There is a ton of ESD info out on the web so have at it...

Later,

Chuck

(Retired Electrical Engineer)

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No pictures, but I connected my shotgun press to my house electrical ground and it does keep the powder from climbing up the inside wall of the shell. My bench is in the basement with an automatic de-humidifier. It doesn't run much in the winter and static is still an issue here.

Maybe I should consider a grounding grid network for everything on the bench.

Concrete floor, steel frame table with a wood top.

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No pictures, but I connected my shotgun press to my house electrical ground and it does keep the powder from climbing up the inside wall of the shell. My bench is in the basement with an automatic de-humidifier. It doesn't run much in the winter and static is still an issue here.

Maybe I should consider a grounding grid network for everything on the bench.

Concrete floor, steel frame table with a wood top.

Google around for antistatic treatments you can spray on your bench and floor. Here is an example (I have no personal recommendations) http://www.qsource.com/p-1645-acl-staticide-2003-general-purpose-staticide-trigger-spray.aspx?utm_source=g&utm_medium=shopping&utm_campaign=shopping&gclid=Cj0KEQiA-ZSzBRDp3ITHm5KO_JYBEiQA1JjHHBpZkrkX-UVxsG1snXgcWPBThcd-g5M8UwHsc9mn-ckaAjTT8P8HAQ

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Ordnance mechanics/techs use the touch off technique described by Chuck all the time to equalize potential, and that technique is described in many Ordnance Publications and Weapon Specs because it works.

"A simple approach to keeping your body at the same potential is to either touch the bench first so any lightning is between your finger and the bench."

^^^

This is good advice, with one clarification....be sure the part of the bench you are touching off to is unpainted bare metal (no anodization or other non-conductive coating), Also, it would be a good idea to make sure your press chassis is grounded to the bench and the bench is grounded to your ground plane (use a standard multi meter to check).

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Ordnance mechanics/techs use the touch off technique described by Chuck all the time to equalize potential, and that technique is described in many Ordnance Publications and Weapon Specs because it works.

"A simple approach to keeping your body at the same potential is to either touch the bench first so any lightning is between your finger and the bench."

^^^

This is good advice, with one clarification....be sure the part of the bench you are touching off to is unpainted bare metal (no anodization or other non-conductive coating), Also, it would be a good idea to make sure your press chassis is grounded to the bench and the bench is grounded to your ground plane (use a standard multi meter to check).

Good point. If the bench is painted, you can still have a static issue even if the metal of the bench is grounded. You could spray some of Gordon's hair treatment on the bench surface to help. Antistatic work benches have conductive surfaces.

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I am an electician. Just use wire 2ga is best, run it to a water pipe, if you house wiring is up to code and copper plumming. Then drill and tap a hole in the bench, add a loop turminal to the wire bolt it to the bench. You can run the wire to an electrical ground if plumming is not grounded. A smaller more flexable wire can be attached from bench to stool.

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My bench is in an unattached garage so there is no water or forced heating. The bench top is raw steel and the garage floor is bare concrete slab. The hillbilly garage wiring (not done by me) is definitely "weird" according to the electrician, but not dangerous. I can reach some conduit through the wall and ground the table to that. That conduit runs underground to the service box at the house. I'm fairly sure that whole loop is grounded but I'll check with the ground fault tester.

There is also a huge Dewalt hammer drill sitting in the garage, so it's just as easy for me to poke a hole in the floor and jam a foot of rebar into the dirt to act as a grounding rod. With the questionable wiring, it may just be the better/faster route.

Humidifying may be an option, but I already have a bias against reloading on rainy days to minimize introducing any humidity into my reloads. It's just a consistency thing.

I try to keep my primers and powder at the same potential as the bench. They're usually in steel cabinets mounted on the benchtop .

Sometimes I'll kick off a shoe and experiment by holding the press and touching my foot to the floor. I think I'll try the suggestion of grounding the stool to the bench (that's grounding to a rod or conduit) . I looked at the ESD straps before I posted, but I'm already bad at knocking stuff over on the bench with two free hands. Tethering my wrist with a ground would just be a hot mess.

BLeKu.jpg

Edited by BitchinCamaro
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My bench is made from an old prison door and has rubber wheeled casters on the legs. The stool at the bench is steel. The static buildup is noticeable, especially since Utah practically has negative relative humidity.

I've read about grounding reloading tables as a good idea , I've just never seen/considered the best way to do it. Aside from going straight ghetto by wrapping some copper wire around a table leg and jamming the other end into "mouth hole" of an electrical socket, what are the best options?

Will a concrete anchor in the floor slab act as an efficient ground, or do I have to get it as deep as a lightning ground?

Is it better to ground myself/stool to the floor, or to the grounded table? Does it matter?

Does anyone have pics of their ground setup?

part-008_zpsq8y5icoo.jpeg

Interesting use of a socket!

I managed to breathe again after looking closer.

Sent from my Nexus 7 using Tapatalk

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What's the deal with British outlets? On US outlets the cover screws are grounded - easiest way to connect, just use a ring terminal there.

Humidifier is your best friend.

Edited by Foxbat
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With a three-pin plug, like the British ones, you could remove two of the pins and just leave the earth / ground pin. This would let you tie stuff into the earth connection of the electrical system (but you may still want a resistor in the circuit for safety reasons, as previously mentioned).

Sent by Jedi mind control

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What's the deal with British outlets? On US outlets the cover screws are grounded - easiest way to connect, just use a ring terminal there.

Humidifier is your best friend.

British system is also 220 v instead of 120.

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What's the deal with British outlets? On US outlets the cover screws are grounded - easiest way to connect, just use a ring terminal there.

Humidifier is your best friend.

British system is also 220 v instead of 120.

Actually, 240V.

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What's the deal with British outlets? On US outlets the cover screws are grounded - easiest way to connect, just use a ring terminal there.

Humidifier is your best friend.

British system is also 220 v instead of 120.

Actually, 240V.

OK, we can quibble. US system is 120, but that figure is 70% of the actual voltage in the sine wave of voltage available, which actually reaches almost 170 volts. In reality, if you plug in a ac meter that isn't RMS certified. you'll see something ranging from 110 to 120, but most often less than the 120 figure due to line loss. Same thing applies to the English system 240v. So while that may be the rating, you're far more likely to see something between 220 and 230. I would have used the term 110 for US voltage, as that is closer to the true actual amount, but I feared someone would pop up and correct me to say "You mean 120". Guess I should have done the same for GB. Anyway, my point was for the uniformed, Britain, like many other countries, do not use the same voltage as the US/Canada, hence the different style plugs.

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And if you have 3 phase power in your shop, you can specify any voltage value you want.

BitchinCamaro, if you live in Utah, why do you have Euro outlets??? And where in the world did you get a prison door?

Ok, the dangerous part is when you pull the hitch pin on the primer pickup tube. If you don't touch off the table/press setup, to lower your potential, then you will transfer the static charge to the primers at that point. When the first primer hits the magazine tube, kaboom.

Ground rods are .010" thick copper plated steel, not rebar.

Don't click on this, it will stick in your head....

bitchin___camaro_redux__d_by_inkmo.png

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What's the deal with British outlets? On US outlets the cover screws are grounded - easiest way to connect, just use a ring terminal there.

Humidifier is your best friend.

British system is also 220 v instead of 120.

Actually, 240V.

OK, we can quibble. US system is 120, but that figure is 70% of the actual voltage in the sine wave of voltage available, which actually reaches almost 170 volts. In reality, if you plug in a ac meter that isn't RMS certified. you'll see something ranging from 110 to 120, but most often less than the 120 figure due to line loss. Same thing applies to the English system 240v. So while that may be the rating, you're far more likely to see something between 220 and 230. I would have used the term 110 for US voltage, as that is closer to the true actual amount, but I feared someone would pop up and correct me to say "You mean 120". Guess I should have done the same for GB. Anyway, my point was for the uniformed, Britain, like many other countries, do not use the same voltage as the US/Canada, hence the different style plugs.

Well, not really. The US standard is 120, not 110, not 115 and not 117. The UK one is 240, but there is harmonization under way, which makes it a bit more confusing, but if you make the equipment for UK, you better set it to 240, as anything else might result in overstress - the UK voltage is allowed to go higher, into over 250V range.

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  • 1 year later...
On 12/7/2015 at 6:50 PM, JimmyB said:

Interesting use of a socket!

I managed to breathe again after looking closer.

Sent from my Nexus 7 using Tapatalk

Ok, not having an electrical background, I want to ground my press however what the heck does this picture depict and why the scissors..?

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Ok, not having an electrical background, I want to ground my press however what the heck does this picture depict and why the scissors..?


The picture shows a lash-up in order to get a 2 pin plug working in a 3 pin socket, via a butchered 3 pin plug. The scissors are being used to bridge what would normally be the fuse in the 3 pin plug.
It's been a long time since I was in the US, so I can't comment on the best way for you to earth your press, but there are other replies in the thread that may be of some use.

Sent from my SM-G920F using Tapatalk

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