Build a Clean-in-Place Device: Projects

I’ve discovered that there are actually a couple of things I don’t like about homebrewing. One is waiting for a new brew to condition in the bottle. The other is cleaning the interior of fermenters and kegs. Glass fermenters are the worst; they seem resistant to even the most aggressive cleaning and require that I manufacture some kind of bent brush or scrubber on a stick.

Even an immediate washing with Five Star’s PBW doesn’t always remove all the scum and kraeusen from the glass. (I fill a newly-empty vessel with water and a half-ounce per gallon of PBW.) But what if I could keep the liquid circulating, constantly washing the interior? Cleaning could be completed without any (or with minimal) manual cleaning. That’s why I decided to build a keg and fermenter washer, one that could run unattended and deliver a sparkling vessel.

So I designed a device to hold the fermenter or keg upside down, spray gallons of cleaning liquid into it and permit gravity to do the work of emptying the vessel. Food service and chemical industries routinely utilize a concept called clean-in-place (CIP), which describes cleaning equipment without moving or dismantling. This project uses a similar concept.

I figured that a tall triangular structure would be relatively easy to construct and would safely enclose a glass fermenter. In addition, an open sided structure would be easier to make and use.

To begin, I traced a fermenter-sized circle on scrap cardboard. Then I drew an 8” line that touched one point of the circle at the line’s midpoint and did not extend into the center of the circle — a tangent line if you remember your junior-high geometry. Next, I drew two more lines that joined each end of the tangent line and extended to a point on the circle, extending beyond. If you’re having troubles imagining this, think of holding a beach ball to your chest while stretching your arms straight out. The ball is held at three points, your chest and at each elbow. In this analogy, your chest is the original tangent line and your arms are the other lines.

Measuring these new line segments disclosed that 12” sides would extend beyond the traced circle. Voila, a three-sided trap with an 8” back and 12” arms. Any fermenter or keg will fit between the open arms.

Calculating the height of the structure was next. Fermenters and kegs are about 25” tall and a small bucket to hold the cleaning solution adds another 8–14” inches to the height. I decided that the total height of the support system should be 30”. So now we have a height of 30” and the back width of 8” plus two 12” “arms.”

I wanted the device to fold flat as well as be adjustable to fit different vessels, so the wings are hinged. But, hey! — there’s an open side to our parallelogram, isn’t there? Three inexpensive solutions for holding the container to our frame are a webbing clamp, cargo tie-down or bungee cord. It will wrap the whole structure, form the fourth side and hold everything together tightly.

So what’s left? A pump, a collar to hold the vessel above the cleaning solution bucket and a spray wand. The spray wand is made of copper tube, although you might choose PVC or stainless steel. It’s drilled to spray radially as well as vertically. We’ll get to choosing your pump in a moment.

Parts List

1” x 2” x 8’ lumber (2) $2.25
15” x 15-3/4” plywood $2.50
door hinges (4) $4.00
copper tube (3/8” x 40”) $1.50
bracket (3/8” tube 4”) NC
72-3/4” brads $1.00
30-3/4” x #8 wood screw $2.00
pump (drill-type) $7.50
webbing clamp $8.00

Tools required

hand saw or power saw
saber saw or jig saw
screw driver(s)
drill and bits
spring-type tubing bender
hammer

Support Stand Construction

The support structure is made of two 8’ lengths of inexpensive 1” x 2” lumber. If you have near zero carpentry skills, this is the project for you. All that’s required is to cut pieces to size, lay the cross supports over the vertical rails and nail them together. However, half-lap joints cut on a table saw are preferable.

Two vertical rails and three cross braces are needed for each of the three panels. For half-laps, each cross piece is cut to half its depth, 3-1/2” in from each end on the same side. Vertical legs are cut similarly at one end and three 1/2” grooves are cut 14” and 3” from the bottom. Once assembled these create an “8” shape. A bit of glue and 3/4” wire brads secure each joint.

Sizes cut from the 1” x 2” x 8’s for my three panels were: six 30” risers, three 8” cross pieces for the back, six 12” cross pieces for the sides.

Adding hinges, which make this device adjustable, is easy. Just screw the hinges to the surface. Since the material is actually 3/4” thick, you’ll need to purchase two to three dozen 3/4” x #8 wood screws (any screws supplied with your hinges will be too long.) Get screws with flat heads and beveled edges and predrill all holes with a 3/32” bit. This will prevent the wooden rails from splitting.

Locate the hinges near the top and two-thirds of the way to the bottom. Be sure the hinges are vertical and square so the wings will fold.

The collar will lay across your bucket and trap the neck of a fermenter or support a keg. So what you’re making is rather like a toilet seat. After some consideration, I decided the opening should be about 6” in diameter. The collar itself is a parallelogram that measures 7” and 13” at the sides and 15” across the front. It approximates the average shape of the uprights and will sit nicely on a majority of buckets.

To make the collar, cut some 3/4” CDX (outdoor grade) plywood to 15” square and cut 20° angles on each side. Locate the center and draw a 6” circle on center. Then drill a 3/4” starter hole inside the circle and use a jig saw or saber saw to cut a nice circular hole. If you have a router, round over all edges, and sand all the edges smooth.

Spray Wand Construction

The spray wand enters from below the collar and must have a “J” shape that allows the neck of your fermenter to extend below the collar. I have several fermenters, so I chose a 3” “J” with a 14” length above the collar. I could have made it 18”, or even 20”, and it would have worked even better.

Using a spring-type tubing bender, bend a “J” into 36–48” of 3/8” copper tubing at 18” from one end. Add a second bend 2-1/2” from the first, making a “U”. Measure up 3” and bend a third 90° angle. To fit this vaguely “b” shaped tube into the collar, you’ll have to cut a slot.

Draw parallel lines to one corner of the collar. Drill another 3/4” hole the same distance from the collar’s edge as your “J” and connect the smaller hole to the larger one.

To secure the spray wand, take a 6” piece of 3/8” pipe and hammer it flat. Bend it into a “U” large enough to wrap the spray wand (about 1/2” inner diameter) and solder it to your spray wand. Be sure the “U” points opposite to the spray wand tip! Bend the ears of your homemade bracket flat, drill a mounting hole at each side and you’ve made a custom bracket. Screw it to the collar and you’re done. You should have 4–6” of leftover pipe protruding from the collar’s edge.
Note: If you plan to use a corrosive cleaner like lye or Five Star’s H.D. Caustic Number 1 or 2, you must use PVC pipe, stainless-steel pipe or other pipe meant to withstand its nature. I’d suggest sticking with safer cleaners, such as PBW, TSP or bleach.

Spray Tip Construction

For your spray tip, you could visit a Tractor Supply Company and purchase one. Or, make a 3/8” deep cut along the copper pipe, then cut in from the side, creating an “L” shape. Bend the extra metal over and gently hammer it down to the remaining tube. File off the extra copper, then solder the seams.

To make the spray holes, select a 1/16-3/32” drill bit and carefully drill one or more holes at the very tip. You can angle the spray depending on your angle of drilling; try to make the holes spray up and sideways. More holes can be drilled radially around the spray tip. I made a few too many. No problem, they’ll easily solder shut.
Pump Selection

Selecting a pump was a unique issue. I thought a larger aquarium pump might be the answer, but didn’t know. Little Giant Pump Company (www.lgpc.com/) makes pumps that can empty oil wells or tiny aquariums and everything in between. I called them for advice and I’m glad I asked.

Their advice was to use an inexpensive drill-powered pump available at home and hardware stores nationwide. They deliver 150 gallons per hour, surely enough volume to wash any vessel, and are self-priming.

Drill pumps are meant to attach to garden hoses, so I recycled a leftover washing-machine hose. It had two female couplings and both the inlet and outlet of the drill pump had male fittings.

I cut the hose unequally as the intake hose must drop into the cleaning solution bucket. The output hose end slips over the 3/8” spray wand pipe and is secured with a screw-on clamp.

That left only one detail, a way to securely hold my ancient Skill variable-speed drill. I chose to make a bracket out of scrap aluminum. It’s simple, just a “U” shape that holds the drill with its handle facing up or down.

When I first turned on the drill, out spewed ancient sludge from the recycled washing-machine hose and some grease stored in the drill pump. So run your drill pump a few minutes before attaching it to your spray wand and clogging the spray holes as I did. (Little Giant suggests lightly lubricating the pump before each use. I suggest food-grade silicone spray, available at most restaurant supply stores and some homebrew stores.)

Does it work? You bet. I can run full strength PBW and not have to throw away five gallons of barely used cleaner. Then all I have to do is sanitize. What could be easier?