Separate Nails from Wood Ash

[JohnnyMX]

We have tons of bonfires and they usually involve pallets which means a ton of ash and nails in the fire pit. I wanted to try this and see if I could keep the ash as long as it wasn't much effort to remove the nails. The fire ring is built for standard pallets to help contain the mess. I built the whole thing with stuff I had from pallets and an old garage door torsion tube. I did have to buy a piece of 1/4" hardware cloth for the screen.
You basically shovel, shake, remove nails with a magnetic wand, and put the charcoal back in the pit. The next process was taking shovels of ash and passing the shovel under my magnetic floor sweeper as a final check for any rogue nails. The nails fly up and stick to the rake right through the ash. The magnets I have just from working with metal in the shop. Doubling and offsetting the screen may reduce the amount that made it through the first sift, but I would probably want second pass anyway just to be sure. I already run the rake around the pit to try and keep any stray nails out of the path of feet and did that when done in case anything fell off when going from pit to sifter.

I ended up with two tubs of clean ash and about 35+lbs of nails. This was a very easy process and didn't take too much time to do.

I made the frame to fit the RTV so it would slide forward/backward but not move much side to side. The tube works really well when sifting as the sifting box slides very easily and nothing gets caught on the round bar.

 

[PILOON]

My separation method is to simply place my magnet inside of a plastic bag and drag it thru the cold ashes.
Works just fine for me.

 

[JohnnyMX]

If I stayed more on top of it that would probably work for me as well. This was about a year's worth since last clean-out. What size magnet are you using @PILOON? Something crazy or just an old speaker magnet or something?

 

[Hughman]

I use an old speaker magnet zip tied to a rake. Hardest part is getting all the nails off the magnet. I like the plastic bag idea.

 

[crashz]

I like the sifting portion. Gives you a nice clean product. Are you spreading this as a soil amendment?

 

[JohnnyMX]

Yes. I will be using the final product in plots and some other plantings around the house. This is why it needs to be 100% nail free. It will get added to what we burn inside the house that never sees nails or anything other than clean firewood. I have also heard of people using old pillow cases to help remove the nails from the magnet which seems like it would work well. The wand grabs the nails and then you just pull up on the plunger and everything falls off and repeat. Wouldn't have bought that for this project, but it is easy if you have one.

 

[2manyrocks]

35lbs of nails from burning pallets is impressive. Must burn a lot of pallets. Also like the fire ring.

 

[JohnnyMX]

We do bonfires all year long and have been burning many pallets as they are free and abundant. I tell everyone we can do fires any time you want, just bring some pallets. This was worst case as there were probably more nails than ash.

 

[Richard]

A bit of work but I've always de-nailed the (only a handful) of pallets that I've had and then, toss pieces onto fire.

Simply not worth the cost or effort to have a rear go flat on me because of an errant nail. Bad enough for a front (backhoe) tire but those rears get downright heavy and awkward! By de-nailing them, I know there's nothing in them verses "thinking" I got all the nails out of the burn area. I can't imagine having 10 pounds of nails. Having 30+ pounds is unfathamable (and not going to happen while I can remove them beforehand!)

 

[PILOON]

If I stayed more on top of it that would probably work for me as well. This was about a year's worth since last clean-out. What size magnet are you using @PILOON? Something crazy or just an old speaker magnet or somethig.

If I stayed more on top of it that would probably work for me as well. This was about a year's worth since last clean-out. What size magnet are you using @PILOON? Something crazy or just an old speaker magnet or something?

I had a store bought 6 inch magnet that I'd simply insert in a sandwich baggy that I'd remove and toss.
Actually collected probably about 2 gals worth of burnt rusty nails that way.
Worked for me, can't complain.
LOL, wife was not happy with my consumption of sandwich baggies.

 

[oosik]

I have a small area where most of the old homestead buildings ( mainly broken up lumber ) were burned. The cleanup and burning of the old buildings happened 30+ years ago. Over the years I will go out with my metal detector and a garden rake. What was found mostly - other than large spikes - short roofing nails.

It's a small area - 15 x 15 - and since it's known - easily avoided with any tired vehicles.

 

[deezler]

I just made a metal sweeper by butchering an old woofer magnet myself. Took a neglected old $5 kids rake toy and bent the metal rake fins around each side of the magnet; works great. I like the idea to throw a plastic bag over it before dragging through ash, though, thanks!

 

[mike0000]

I like the screen sifter you built. I also made a tool/wand with strong magnets on it. I always worry I may miss some of the nails with the magnets only to later find them with a tire.
I think I’ll add a screen to my process, thanks for posting your process.

Mike

 

[JohnnyMX]

I am definitely going to add a second or third layer of screen and try to offset them to catch more nails in the first sift. Smaller nails will go through the 1/4" cloth. Most framing nails size will get stuck as the head is too large to pass, but you do find many nails hanging through the cloth by the head. I would feel much more comfortable if the second sift was purely for insurance and I found next to no nails. I ordered a 50' roll as it is a few bucks more than a 5' piece at home depot, so I can play until I get it right.

 

[2manyrocks]

Most pallets I've seen tend to use something like 8d spiral shank nails to attach the thin deck boards to the 2x4 runners. Difficult to pull out in one piece. So I get why you'd burn the pallets and try to separate the nails later. But 1/4 screen may not be fine enough to separate all of the 8d nails or pieces thereof.

There are some rock screen threads here that might have some useful ideas. I seem to recall many of them being built at an angle so gravity helps to pull the material through the screen. A steeper angle might also help to separate nails if the ash falls through the holes, but the nails tend to roll off the top.

Another idea that came to mind would be to vibrate the screen box with an air hammer if you happen to have one.

 

[cwbyeng1300]

Put your magnet in a steel can. When you want to clean it, just pull the magnet from the can & everything falls off.

 

[KilroyJC]

Occasionally( ) the odd piece of lumber with some nails/screws/staples end up in one of our wood stoves or the fire pit.

i use an old gem-mining screen to sift out the metal bits. Basically a rectangular frame 12x20 with a pierced-metal bottom, 1/8” holes on 1/8” alternate spacing. It works quite well - Other than having to be very conscious of wind direction…

 

[rontaki]

Old desktop 3½" hard drives have strong magnets in them, easy to harvest. The magnets used small laptop drives are not as powerful, though.

The older hard disk drives tend to have larger magnets than newer drives, as do higher performance drives.

Of course, no magnets to be found in Solid State drives.

 

[sixdogs]

My separation method is to simply place my magnet inside of a plastic bag and drag it thru the cold ashes.
Works just fine for me.

This works the best for me as well.

 

[alpha&omega]

Old desktop 3½" hard drives have strong magnets in them, easy to harvest. The magnets used small laptop drives are not as powerful, though.

The older hard disk drives tend to have larger magnets than newer drives, as do higher performance drives.

Of course, no magnets to be found in Solid State drives.

Same goes for old microwaves. Powerful magnets, but the disassembly is dangerous if you don’t know the hazards associated with it.