At the risk of stating the obvious, the first thing you’ll need to build a stainless steel rain barrel is a stainless steel barrel. These, I should say right off, are not so easy to come by — at least not at a price most would consider reasonable. This is one of those “packrat” projects that came about because I had some interesting materials on hand and was looking for something (hopefully) equally interesting to do with them. If you’ve already got a barrel and/or just want to read about how I built the thing, skip down to the numbered steps below. If you’re curious about how I came by the magic barrel, read on.

This is my barrel, this is my drum

When I was wrapping up organic chemistry grad school, I had a biochemist pal who had recently graduated and was doing pretty well on his own, running a small startup selling an exotic but promising nutritional supplement derived from buckwheat. He was really a repackager, buying the stuff from a bulk natural products house in New Zealand, then encapsulating, bottling, and marketing it in the US. Anyway, this guy wanted to experiment with direct extraction of his product from raw plant material, with an eye to someday becoming his own supplier, and offered to hire me to set up a small pilot plant.

That, I think, was when I first saved the eBay search for “stainless steel drum.”

That project fell by the wayside, in pretty short order, when I figured out the real hurdle wasn’t the extraction or any of the wet chemistry — it was going from a dilute solution of the stuff we wanted, in water, to a nice dry powder that you could put in capsules, and doing it in a way that was cost-effective and safe. The cost for the necessary drying equipment, even for a small plant, was just prohibitive.

So it goes. But I never canceled that eBay search, and so three or four times a week, for months afterward, I got an e-mail alert every time a used stainless steel drum came up for sale. I didn’t mind. I have a bunch of saved eBay searches running like this, and I look forward each morning to seeing what’s popped up overnight.

Well, you can guess how this story ends: eventually a deal came along that was too good to pass up. The seller was just 100 miles away, and started the listing at $0.99. I bid a dollar, and no one else bid. Even with shipping, the total came to less than $100, which is a heckuva deal. A new stainless barrel from U-LINE, for instance, will set you back more more than $700. This one had been used to contain Dr. Pepper syrup, in its former life, and while I sure wasn’t going to eat out of it, it wasn’t like it had been full of 2,4,5-trioxin.

CAUTION: If you buy a used drum, be darn sure that whatever was stored in it during its former life is nontoxic, biodegradable, environmentally friendly, and water soluble. You should be sure of this before you buy the thing, doubly sure before you cut into it, and triply sure before you wash it out onto the ground.

The seller took his time with shipping (and I don’t especially blame him considering how much labor he lost on the deal), so I had stopped looking out for the drum’s arrival by the time the UPS driver actually dropped it off on my front porch a few weeks later. There was a loud metallic clang, a string of muttered curses, and, finally, the sound of a delivery truck receding into the distance.

I opened the door, and there she was: dead, wrapped in plastic, with a shipping label slapped on one side. I wobbled it around the side of the house to the garage, tore off the wrapping, and examined my prize.

There were a couple of minor disappointments—a saucer-sized large dent that stood out among the smaller dings and scratches I’d seen in the photos and expected, and a side bung closure that turned out to be just a flimsy cap made of rusty sheet metal, for instance—plus one that I found more irritating: While the top, bottom, and walls of the drum—all the inside surfaces—were stainless, the rims were not. If I wanted to use the drum outside, I’d have to paint or otherwise protect them.

Magnet sticks to carbon steel drum rim, left, but not to stainless steel drum wall, right. Visible oxidation on rim, of course, is also a clue.

Still-in-all, I felt I’d gotten my money’s worth. Only one problem, now: what the heck was I going to do with it?

Enter Rain Man

My house is built on a fairly steep hill, and has a gutter and downspout on the uphill corner, with a buried corrugated drain pipe that carries runoff down the hill to the street. I was puttering in the yard, one morning, when it occurred to me that a rainwater reservoir on that corner would be elevated over most of the rest of the yard, and could be fit with a hose that would gravity-feed water almost anywhere I wanted to use it except the relatively small corner at the top of the hill.

Rain Barrel Location

Raising the reservoir on a platform, I reasoned, would only increase its usefulness. Several close friends and family members had installed commercial rain barrels, and though I always thought harvesting rainwater was cool, I was never very impressed with how the off-the-shelf barrels looked. I wanted something a touch classier than a green plastic barrel with fake wood grain on a stack of cinder blocks. My stainless barrel was sitting in the garage, waiting for a use, and after tilting my head at it for awhile I realized I could turn it “upside down,” use the top bung to mount a valve, and use the side bung for an overflow line. I had a stack of Dek-Blocks on hand, from an old project, that I could use as piers for an elevated platform, and I knew there had to be some cheap off-the-shelf 55 gallon drum cover that could be fit with a screen to keep leaves and bugs out. Interested now, I hopped into SketchUp to make a concept rendering.

My initial concept rendering, with former MAKE product development engineer Eric Weinhoffer for scale.
My initial concept rendering, with former MAKE product development engineer Eric Weinhoffer for scale.

This was starting to seem like fun. I wasn’t committed yet, but curious enough to go out to the garage and start poking through my junk piles parts inventory for stuff that I could maybe use to plumb the thing. And that’s when something happened that can only be described as…

A Minor Junkbox Miracle

Before the infamous TV show, I was known to describe myself as a “hoarder.” Now, having come to understand what that term really means, I’m happy to settle on “pack-rat.” I have always saved broken stuff and picked up random junk that looks like it might someday be useful. When I was younger, it just accumulated in messy heaps. What counts for maturity, in my case, has been the development of a limited discipline that allows me to sort and keep all this stuff in some semblance of order so that it’s actually possible to find what I need when I need it. But it has been an uphill battle.

Anyway. As much frustration as my pack rat tendencies have sometimes caused myself, my friends, and my family, it’s worthwhile to remember those moments when it has paid off. And it does pay off, all the time — I am literally surrounded by stuff I built or repaired using scavenged materials. I’ve saved a lot of money, and it’s brought me great personal satisfaction (for whatever weird reasons). The routine positive experience involves being able to find just the right screw, nut, bolt, washer, or other small fastener right there, on hand, right when you need it, instead of having to make a list and go to the hardware store, then go back for the stuff you forgot, then go back again to exchange for the right size, etc., etc.

But there have been a couple of absolutely epic, gloriously vindicating pack-rat moments in my life. One of these was when I discovered that the large diameter O-rings I’d had to buy in a 100-count bag to replace the single, worn-out ring in our pool pump filter housing were exactly the same part used as the drive belt in our Harbor Freight rock tumbler. Rock tumblers have to run for days and weeks at a time, and you can pretty much count on wearing out one of these belts every time you polish a load of rocks. Sure enough, my nephew broke a belt in the middle of a run, and I was frustratedly trying to run down a replacement online when I discovered that, thanks to a lucky coincidence and my inability to throw away parts, I actually had 99 of them sitting there on the shelf in a bag.

Another was when, while digging around for rain barrel parts in my “pipe fittings” bin, I came upon this thing:

I don't know exactly where this thing came from. My best guess is that it was among the bits of dumpster-bound junk in several large boxes of old parts we cleaned out of the mass spectrometry lab I worked in during grad school.
I don’t know exactly where this thing came from. My best guess is that it was among the bits of dumpster-bound junk in several large boxes of old parts we cleaned out of the mass spectrometry lab I worked in during grad school.

It’s 2″ diameter, 4-ft. industrial-grade rubber hose armored in stainless steel wire braiding. It matches my stainless steel barrel perfectly, and has a male NPT fitting on one end and a four-bolt flange fitting on the other. It was exactly the right length to reach between the side bung on a 55 gallon drum, if it were slightly elevated on a stand, and the opening of the existing underground corrugated drain line on the uphill corner of my house. It’s a 5″ flange. The drain line is 6″ diameter pipe.

I was almost relieved to discover that the male NPT fitting on this hose was slightly undersize for a standard 2″ NPT 55 gallon drum side bung, and that I was going to need an adapter bushing. If it had fit perfectly, right off the shelf, the serendipity here would’ve been downright spooky. In any case, the discovery of this object was clearly a sign from the junk-box gods: Project Rain Barrel was a go.

Project Steps

Cut the top off the drum

Drill a 3/8″ hole in the bottom of the drum (i.e. the end without the threaded bung) right near the rim.

Mount a 24-threads-per-inch (TPI) (or higher) high speed steel (HSS) blade in your reciprocating saw. The blade should be long enough to reach the hole with the saw resting on top of the rim, rather than inside it, so you can cut real close to the edge.

Set your saw on a medium-slow speed, add a drop of cutting oil every now and again, and patiently cut your way around the rim to remove the end of the drum. You will probably dull a couple blades along the way. I went through three and a half.

Clean it out

CAUTION: I said it before, I’ll say it again: be absolutely certain that whatever was stored in your drum is nontoxic and biodegradable. In my case, the drum had been full of Dr. Pepper syrup (which is at least arguably nontoxic) from the old plant in Waco.

Now that you’ve got the end off, set the drum open-end up on three of your Dek-Blocks out in your driveway or some other outdoor area with good drainage near a hose tap.

Reel out the hose and wash out the inside of the drum. Take your time and get it nice and shiny. Oooooooh, pretty.

Paint the rim

If your drum is plastic or all-stainless or otherwise has a non-corroding rim, of course you can skip this part. Mine did not.

First, mask off the rim. The mask-line around the side would be visible in the finished build, so I masked it pretty carefully with blue painters tape and a section cut from a plastic drop cloth. The inner mask-line on the end, however, would be hidden up underneath, so it could be a bit sloppier. The cut-out steel circle from the other end of the drum was naturally a pretty close fit, so I wrapped it quickly in a plastic bag and just set it in place to cover the end.

Spray paint the mask drum end per the directions on the can. I used up the can, applying as many coats as I could for longevity.

Remove the masking when the paint is just dry to the touch. Then wait for it to fully set up before moving the barrel or handling it in any way.

Cut the lumber

We’re using rough-cut timber, which means that, though it’s still not actually the size it says on the stock tag, it is slightly bigger than standard dimensional lumber. For instance, a standard nominal 4 x 4 post is actually 3-1/2″ x 3-1/2″. The rough-cut size used here is closer to 3-11/16″ x 3-11/16″. Likewise, our nominal rough-cut 2 x 6 beams are actually 1-5/8″ x 5-5/8″. You can certainly use standard dimensional lumber if you prefer, but note that all the downloadable templates here assume the above rough-cut measurements.

Carefully measure the and mark the halfway point along your 8-foot 4 x 4 post, then it in half at the mark. My miter saw wouldn’t cut all the way through on a single pass, so I made the deepest cut I possible could, then unplugged the saw, rotated the post 90 degrees, carefully aligned the blade with the existing saw cut, plugged the saw back in, and completed the cut. Repeat the process with each of your 4′ segments to make a total of four 2′ (24″) posts.

As above, cut your 12 foot 2 x 6 beam exactly in half, then cut each of those pieces exactly in half, to make a total of four 3′ (36″) beams. Both posts and beams will likely come out a tad shy of their “ideal” dimensions because of the width of the saw blade cuts (the “kerf”) — that’s OK. The important thing is that they all be the same length, or very close to it.

Notch the beams

I’m a big believer in printable paper templates. Even the most humble desktop printer is capable of almost thousandth-of-an-inch accuracy, these days, which is a heckuva lot better than I can measure by hand. Rather than stress over manual layout work, I prefer to design complex cuts in software (I usually use Illustrator, but InkScape is just as good), add indexing marks, then print to scale, apply to my workpiece with tape (or by printing onto full-page adhesive mailing labels), then just cut or drill to the lines. This project uses three such templates. You can download the first of them, which is used to locate drilling centers and cut lines for the four half-lap joints between the various beams, here. Print four copies at 100% scale.

Measure and mark the center of each of your 36″ 2 x 6 beams. Fold each of your templates over precisely, longways through the diamond, then cut out the little diamond shaped-area. This is a “window” that lets you index the centerline with the witness mark on your beam. Open the folds up to 90 degrees, then line up the templates on your beams and tape them in place securely around the edges. The gray areas indicate wood to be removed.

Use a handheld drill with a guide (or a drill press) to drill four holes in each beam, where indicated on the template, to locate the inside corners of the two notches.

Use your reciprocating saw with a wood-cutting blade to cut along the lines from the edges to each hole, and between the two sets of holes. Save the scrap cutouts, for now. Peel off and discard the templates.

Drill the beams

Make two stacks of two beams each. Rotate the notch cutouts so that the planed thickness of the scrap is aligned along the length of the beam, then tap two of them into each set of overlapping notches. This is to make sure that the notches remain closely aligned during the subsequent drilling operation. Make two witness marks on the long edge of the upper beam in each stack — one 12″ to each side of its midpoint.

Download the beam/post drilling template, print 2 copies, and cut each page in half to make 4 templates. Fold each template to 90 degrees on the short edges, rotate it so that the gray box is closest to the ends of the beams, and position it with its inside edge just outside the witness mark. Use blue painter’s masking tape to tape it down on all four edges.

Using a power hand drill, drill guide, and 1/2″ twist bit, drill holes everywhere indicated by the templates all the way through both beams in each stack. Remove and discard the templates and the notch scraps, and separate the beams. Mark each pair of beams with a pencil, right in the center, on the two faces that meet in each stack. Mark one pair with Os and the other with Xs.

Drill the posts

Print 2 more copies of the the beam/post drilling template and again cut each page in half to make a total of 4 templates.

This time, fold each template 90 degrees on the long edges. The orientation of the gray box does not matter, for the posts. Position the outside edge of each template 5-1/2″ from one end of the post and tape along all four edges.

Using a power hand drill, drill guide, and 5/8″ spade bit, drill holes everywhere indicated by the templates all the way through the posts.

Assemble the stand

It’s a good idea to apply a weatherproofing compound to the wooden pieces of the stand before putting them together. I used Thompson’s WaterSeal “Advanced.” Lay the cut timbers out on a drop cloth and apply the weatherproofing agent per the label directions, making sure to observe the recommended drying time before proceeding.

Pick a matched pair of notched beams, and align them with the notches up and the marks facing each other. Arrange the other pair of beams with their notches down, at right angles to the first pair, again with their marks facing each other, and carefully slot all four beams together. Tap gently with a rubber mallet, if needed, but if the notches don’t interlock, take them apart and adjust with a rasp, as needed, to achieve a “gentle tapping” fit. Don’t try to pound them together or you may split the wood.

Arrange your concrete piers in a square where you intend to set up the finished barrel. Insert the posts into the piers with the holes uppermost.

NOTE: Most piers are sized for standard dimensional lumber, and you may need to shave or file the corners of these rough-cut posts, just a bit, to get them to fit.

Lower the interlocked beam assembly over the upright posts and align the bolt holes. Put a flat washer over the head of each of eight 1/2″ x 8″ galvanized steel hex bolt, then pass two bolts through each post and the adjacent beams. Tap gently with a rubber mallet, if needed, to run the bolts all the way through.

Add a second 1/2″ flat washer over the exposed threads of each bolt, followed by a 1/2″ split lock washer, followed by a 1/2″ hex nut. Thread the nuts on just loosely, for now.

Install the barrel

Once the paint on the rim is completely dry, invert the barrel and set it on the stand between the four posts, with its weight resting on the crossed beams. Adjust the position of the piers, posts, and beams as needed to correctly position the barrel relative to your gutter downspout, and so that all the posts are as close to plumb and the beams as close to level as possible. Then use a pair of wrenches to tighten down the hex nut on each of the bolts.

Fit a rubber washer into each of the threaded openings in the gate valve, then thread a M/M 3/4″ NPT – hose thread adapter into one side, and a 2″ 3/4″ NPT stainless steel pipe nipple into the other. Use a wrench to turn thread the valve assembly, via the free end of the pipe nipple, into the threaded bung on the (now) underside of the barrel. Get all the joints nice and tight, and make the spicket handle is oriented at a convenient angle for hand operation.

Attach your overflow line to the drum’s threaded side bung. In my case, this meant first installing the 1-1/2″-2″ NPT F/M reducer bushing, then threading the 1-1/2″ M NPT threaded end of my braided hose assembly into that.

Cut the cap and gasket

If you’re working with a flange fitting like mine, you can download the gasket template here. Print one copy at 100% scale, cut out the two circles, and affix one of them to a sheet of 1/16″ thick gasket rubber, and the other to the top of a flat 6″ PVC pipe cap.

Use scissors and/or a sharp hobby knife to trim the gasket rubber to shape, as shown.

Use a drill with a fly-cutter to remove the large center section from the PVC pipe cap, then normal twist drill bits to make the bolt holes. Accuracy will be best if you center punch, then drill a small pilot hole, then step-drill up to finish diameter.

Remove and discard the template scraps.

Fit the flange cap

Turn the flanged end of the hose assembly so that the bottom is facing up, then apply the gasket over the flange and align the bolt holes.

Align the openings in the PVC pipe cap with those in the gasket, then pass a 1/2″ x 2″ stainless steel hex bolt through the top of the flange, through the gasket, and through the PVC pipe cap.

Add a flat washer over each bolt, followed by a split washer, followed by a hex nut. Use a pair of wrenches to tighten the bolts securely into the nuts. Compress the split washers completely and the gasket material slightly, but don’t overdo it or you may damage the plastic pipe cap.

Connect to existing drain line

Remove the existing downspout and associated hardware, exposing the open end of the corrugated plastic drain pipe.

Fully loosen the hose clamp on the narrow side of the flex-coupling reducer fitting and slip both hose clamp and reducer over the corrugated pipe. A touch of water-based lubricant makes this process a lot easier. Insert the pipe at least as far as the widening part of the reducer throat, then position and tighten the hose clamp securely.

Fully loosen the hose clamp on the wide side of the reducer, without removing it, then slip the PVC pipe cap diameter into it. As before, a drop of lubricant may be very helpful. Once the pipe cap is firmly seated, adjust and securely tighten the remaining hose clamp.

Add the cover

Test the water-tightness of the gate valve and overflow line junction by running water into the top of the drum from a garden hose. Fill until water starts to flow out the drain line, then turn off the water and let it set for several hours. If either fitting leaks, drain the barrel, disassemble the offending joint, and use Teflon tape, thread sealant, or other means to improve the seal. Repeat until the barrel can sit full to the overflow line, for 6 hours, without any drops falling on the ground nor any droplets hanging from the valve or the side fitting.

The plastic drum cover is designed to convert a standard 55-gallon drum into a recycling bin. Fit it in place over the open top end of the drum.

Set a stainless steel wire mesh colander in the opening in the drum cover. Add 6–10 smooth river stones to the colander to weight it down.

Install the downspout

Assemble stock gutter fittings as needed to carry water from your overhead gutter to the opening in the center of the drum cover. In my case, this meant one more “in plane” elbow fitting (in addition to the one that was already mounted on my gutter downspout), one “out-of-plane” elbow fittings, one 15″ straight extension, and one more “out-of-plane” elbow.

Interlock the fittings and secure each joint with at least one sheet metal screw, then paint the assembly with exterior latex in the color of your choice.

If your installation requires moving water through a horizontal distance to get it from the gutter to the drum, as mine did, you’ll need to arrange for something to support the free end of the gutter. I used a short length of stainless steel wire rope for this purpose.

To attach the wire rope to the gutter, I used an off-the-shelf downspout clip fit with an eyestrap, as shown. There’s almost no clearance between the clip and the gutter fitting it attaches too, and I needed a low-profile fastener to fit in this space. I ended up using aluminum pop-rivets, inserted from the inside of the clip up through the eyestrap mounitng holes, as shown. I had to drill two 3/16″ clearance holes in the back of the clip to match those in the eyestrap.

I installed a screw hook in the eave directly over the barrel to support the weight of the gutter extension. I just drilled a 1/4″ hole in the wood and then turned the screw in by hand.

Finally, I connected a 24″ span (32″ counting the doubled-over lengths at the ends) of 1/8″ galvanized vinyl-coated wire rope between the eyestrap on the gutter and the screw hook in the eave. Each end of the wire rope is run through a “thimble” to prevent kinking, and then doubled over and secured with two 1/8″ stainless steel rope clamps spaced about 3″ apart. Cut away any excess rope with small bolt cutters.



So far I'm pretty pleased with how the barrel looks and works. Other than occasionally emptying leaves out of the colander, it has so far required no maintenance whatsoever. One disadvantage of using the side bung for the overflow line is that only about half the drum's capacity is used. Before next spring I may try to add some "riser" plumbing to the side bung, inside the barrel, to increase the overflow level. A full 55 gallons of water weighs about 460 lbs., but I'm confident that's well within the limits of the stand.

The gate valve is tough and reliable but slow to operate. For day-to-day use, I tend to leave it open and attached to a pro-grade black rubber garden hose terminated with a Gilmour 528T solid brass twist hose nozzle which I can open and close as needed at the hose's water-dispensing end.

One of the great advantages of a metal rain drum, which I did not anticipate during design, is the sound. When it rains, and water is flowing off the roof, down the gutter, through the spout, and into the barrel...well, the whole system makes these amazing melodic dripping noises that you don't get from a plastic barrel.

If you have ideas, questions, comments, or rain barrel stories of your own to share, we want to hear from you! Please sound off in the comments below. Thanks for reading!