Laminar Flow Fountain

The internet has many fascinating things to see. A recent interest of the digital masses is laminar flow, which can cause water to create streams so smooth that they appear to be glass rods. Now, imagine having your very own water fountain which demonstrates this phenomenon. This Instructable will give you directions on how to make just that.

I decided to create a laminar flow fountain for my SIDE project in my Principles of Engineering class, because I observed that not many students created water features for their project. Most materials, tools and guidance was provided by my POE teacher Ms. Berbawy. I followed most of the instructions to make the fountain from the original creator of this project, Larry Cotton, who published it in Volume 32 of Make: Magazine.

For the fountain's nozzle:

• x1 40 oz peanut butter jar
• x1 pipe connector(to be used as spacers)
• x1 pack of scouring pads, about 1/4" inch thick (you'll need to use 2-3 pads)
• x1 3/4" to 3/4" PVC adapter fitting
• x1 3/4" threaded female adapter
• x1 pack of straws, preferably 1/4" diameter (you'll need to use about 30-40 straws)
• x1 roll of aluminum window screening (you won't use much of it)
• x2 #17 O-rings

For testing the nozzle:

• x1 one-way water shutoff
• x1 garden hose

For the nozzle's holder:

• x1 4" inner diameter PVC pipe
• x1 1/8" thick, x 3/4" wide flat aluminum bar
• x3 #6-32 1" Phillips drive machine screws
• x3 #6-32 hex nuts
• x6 #8-32 1/2" Phillips drive machine screws
• x6 #8-32 hex nuts
• x1 roll of weatherstripping

For the fountain:

• x1 20-gallon pond liner
• x1 1/8" thick, 1/2" wide flat aluminum bar
• x2 #8 1" Phillips drive sheet metal screws
• x1 3"x3" sheet of cast acrylic (you'll cut a 2.75" diameter disk from it)
• x1 #6-32 1/4" Phillips pan head machine screw
• x1 1/2" inner diameter vinyl tubing
• x1 1/2" to 3/4" barbed adapter fitting
• x1 1150 gph submersible water pump
• x1 1/4" inner diameter rubber grommet
• x1 replacement plug

For the fountain's stand:

• x24 sheets of 1/8" thick, 12" x 24" birch plywood
• Wood glue
• x6 #10 2" wood screws
• x1 7/8" diameter wooden dowel
• Silicone waterproofing spray
• Spray paint (doesn't have to be this color)
• x3 1.125" diameter plastic furniture glides

Tools:

• Universal Laser Systems laser cutter(model used is no longer sold, but others are available)
• Drill with 3/4" hole saw, 1/2", 1/4", 3/16", 11/64", 9/64", and 3/32" drill bits, and Phillips driver bits
• Drill press(optional)
• Dremel with attachments(you will need a cylindrical and conic attachment for sanding)
• Hacksaw
• Heat gun(optional), or a household hair dryer
• x15 Heavy-duty ratchet clamps
• A brake to bend metal(optional), or a bench vise
• An X-acto knife
• Wire cutters
• Wire strippers
• Adobe Illustrator
• Fusion 360
• Sandpaper (320 grit)
• Needle nose pliers
• Rubber mallet
• Tin shears
• A metallic and normal permanent marker

Modify the jar.

First, drill a 3/4" hole at the bottom of the jar, in the center. This will be where the adapter screws in. Cut or sand off any bits around the edge of the hole. Drill a second hole of 1/2" diameter in the lid, also in the center. This will be the hole from which your water flows out. It is best to create a pilot hole with a small drill bit first, and then slowly increase the size to 1/2". Be careful while drilling the hole, as the plastic may fracture, as shown(1), if you drill too large of a hole at too fast a speed. Sand the edge of the hole in the lid from the top to give it a sharp edge, which is important to creating laminar flow.

Create the spacers.

Cut off x2 1.25" wide segments of the pipe connector on either side. Then, cut out approximately 2 inches out of the segments, opening the ring. This will allow you to squeeze the spacers into the jar. Use the heat gun (or hair dryer) to accentuate the curve of the segments, making them easier to fit into the jar. From one side on each spacer, cut three tabs, 120 degrees apart, 1/4" deep and wide, using a hacksaw. Bend the tabs inward to 90 degrees with the help of a heat gun and needle nose pliers. These tabs will hold the items in the jar in place, preventing them from falling through the spacers.

Cut materials.

Cut out x5 3.75" and x3 1" diameter disks from the scrub pads, x2 3.75" diameter disks from the window screening, and cut apart as many straws as needed (about 30-40 straws) into 1.75" segments. These will all act as filters to slow down the flow of water in the jar.

Put the parts together.

Insert the 3/4" to 3/4" PVC adapter fitting, with a #17 O-ring on the threaded side, through the hole at the bottom of the jar, threaded side down. At the top end of the adapter fitting, insert the three 1" diameter scrub pad disks. Put in one window screen disk on top of the adapter. Put in one of the spacers, with the tab end facing down. Inside the spacer, put in four of the five 3.75" diameter scrub pad disks (you may need to trim them down a bit). On the stack of scrub pads, carefully insert your straw segments, and make sure they are packed tightly enough so that they do not move around in the jar. Place the 5th 3.75" diameter scrub pad disk on top, along with the other window screen disk. Then, insert the other spacer with the tab end facing up, around the window screen, scrub pad and straws. if you cannot put the spacer around the straws, try wrapping the straws in a thin, stretchy rubber band first. An accident made my nozzle slightly different, but as long as the items are securely compacted together, your nozzle will function properly. Screw the lid on, and make sure it is tight.

At the bottom, loop another #17 O-ring around the adapter fitting. Screw on the female threaded adapter, with the rubber ring inside the threaded adapter facing outward(2).

To test if your nozzle produces laminar flow, attach the water shutoff in the off position and the hose. Make sure your hose is attached to an adequate water supply, and turn the water on. Turn the shutoff to the on position, and once the water is flowing out, check to make sure your stream is laminar. With the nozzle facing upward, the stream should shoot at least 1' high. Wait at least 1 minute before checking your stream. If you see bubbles at the base of your stream, your hole may not be properly sanded, or there may be air trapped in the nozzle.

Cut parts to size.

Cut down the PVC pipe using the hacksaw to about 16.8". This will be the main body of your nozzle holder. From the 3/4" wide flat aluminum bar, cut 10-inch segments (you may need to mark where to cut using the permanent marker) using the hacksaw. Sand down the cut edges of the pipe and bar segments with a Dremel using the cylindrical sanding attachment to prevent injury.

Drill holes into the body of the holder.

Measure the height of your jar, excluding the adapters. Make three marks(using the metallic marker), 120 degrees apart, at your jar's height away from one end of the pipe. At the other end, make two marks, about two inches apart, in line with the marks at the other end. The bottom mark of the two should be no more than 1.5" inches away from the edge of the pipe. There should be a total of six marks at one end and three at the other.

Use the 9/64" drill bit to make the three holes at one end of the pipe, and the 3/16" drill bit to make the six holes at the other end. If you are using a drill, make sure that it is straight while drilling into the pipe.

Bend and drill holes into the aluminum bars.

Using a brake or bench vise, bend the three aluminum bars in the middle to about 38 degrees. At one end of the bars, make two marks in line with each other, two inches apart, no more than 1.5" away from the bend. Then, using the 3/16" drill bit, drill holes through the metal at the marks using a drill press (or the bench vise and a drill). Sand down the edges of the holes using the conic sanding attachment with the Dremel to prevent injury.

Attach bars and screws.

Insert the #6-32 screws into the three holes at the top, and screw on the #6-32 nuts on to the inside of the pipe. At the other end, attach the bent bars with the #8-32 screws and nuts. Make sure the nuts and screws are fixed tightly to the pipe.

Design your stand feet.

Your fountain will have three stand feet and a disk, but you only need to design one foot (unless you want to have different designs for each foot). Use Fusion 360 to design your feet. The foot should be an L-shape, with the fountain resting in the bend of the L. For the pond liner I used, the diameter of the bottom was about 15.1". The part of the foot underneath the fountain's basin should be 6" high, with a notch at the top to fit the disk on the stand, which will be 0.75" wide. The notch should run 7.0625" along the foot. My stand feet were about 16.3" long, and their thickness will be 0.75". The total height of my foot was 11.75", due to the size restraints of the laser cutter and boards.

Cut out and glue together your feet and disk.

Transfer your design to Adobe Illustrator, on to a 12"x24" artboard. It is best if your document is set up in 'Layout' mode, which you can get to by going to 'Window' > 'Workspace' > 'Layout'. Convert your design to vector lines, and change the document color mode to RGB by going to 'File' > 'Document Color Mode' > 'RGB Color'. Set the vector lines' color as RGB Red, or R255, by clicking on the red swatch in the Swatches window. Set the weight of the line as 0.1 points. Make sure your design is at least 0.05 inches away from the edges of the artboard. Send your design to the laser cutter to cut out your feet from the plywood. You will need to use 9 or 18 sheets of wood, depending on how large your design is.

For your disk, simply create a circle on a new document with a diameter of 15 inches, and cut it in half, making two semicircles. Position the semicircles so that they both fit on the artboard without intersecting each other. Make sure the semicircles have the same specifications of the foot design, being RGB red with a stroke weight of 0.1 points and at least 0.05 inches away from the edges. The disk will use a total of 6 sheets of plywood.

After cutting, assemble your feet and your disk. Each foot should be 6 sheets thick. Glue the sheets together and clamp them down to squeeze out excess glue. Be sure to scrape the excess glue off while it is wet, as removing it after it is dry is a very time-consuming task. For the disk, line up your semicircles to form the full circle, and alternate your layers to ensure the best integrity for the disk. The glue should take 2-3 days to fully solidify.

Paint, assemble, and waterproof the feet and the disk.

Once your glue has solidified, spray paint your parts on each side. The spray paint I used took 30 minutes to fully dry.

While it dries, cut the 0.875" diameter dowel to 6 inches. Drill pairs of holes 3" apart, using the 3/16" drill bit, with the pairs 120 degrees apart. Make sure the bottom holes of the pairs are 0.5" apart along the length of the dowel, so the screws do not run into each other.

Once the feet are dry, line up the pairs to each foot, so that each foot has a pair and when properly aligned, the feet are 120 degrees apart. Mark the hole locations on the legs and drill the holes 1.25" deep. Attach the legs to the dowel using the #10 2" screws.

Put the disk into the slot, then spray the entire structure with waterproofing spray. The spray I used took 24 hours to completely dry.

Drill a small hole using the 3/32" drill bit in the bottom each foot, about 0.5" deep. Hammer in the three furniture glides using a rubber mallet.

Cut your pieces.

Cut about 43" from the 1/2" wide flat aluminum bar. Sand down the cut edge using the cylindrical Dremel attachment. Use a drill press/drill with a 9/64" drill bit to make a small hole in the center of the bar, no more than 4" from one end. At the other end, make two holes in line at the center, at least 6" apart. The bottom of the two holes should be no less than 3" from the end. Sand down the holes using the conic Dremel attachment. Put the metal into the fountain basin vertically, against the wall, with the single hole end facing up. Start a curve in the metal from the top edge of the basin to end in the center. The single hole should line up with the center of the basin. This is the support arm for the deflector.

In an Adobe Illustrator document, create a circle with a diameter of 2.75", and create another circle in the center with a diameter of 0.1". This will be cut from the acrylic. Make sure your shape has the same specifications as your foot design. Use the laser cutter to cut it from the acrylic sheet. This will be your deflector.

Assemble your parts.

Attach the straight end end of your metal bar to the basin using the #8 1" sheet metal screws. Do not pre-drill the holes, as the screws themselves will be used to make the holes to prevent leaks. Attach the deflector to the other end using the #6-32 1/4" screw.

Install the pump.

Drill a 1/4" hole on the wall of the fountain basin, near the bottom. Cut off any excess plastic using a X-acto knife. Insert the 1/4" inner diameter rubber grommet into the hole. Cut off the plug head from the cord of the water pump, and thread it through the hole. Replace the plug head with the replacement plug using wire cutters, wire strippers, a X-acto knife and a Phillips driver bit. For the model of the pump linked above, the brown wire should be positive, and the green-and-yellow wire is ground.

Attach the pump to the nozzle.

The pump linked above should come with several barbed adapters to attach a tube. Use the 1/2" adapter from the pump with the other barbed adapter of the same size. The other barbed adapter should screw into the female threaded adapter on the nozzle. Attach the vinyl tube. If the tube is too long, you can cut the tube to size.

Put the nozzle inside the nozzle holder, and put the holder in the center of your fountain. Place your completed fountain on your fountain stand. Fill the basin with about 3 gallons of water and plug in the pump. You can adjust the position of your nozzle holder or deflector supporting arm if needed.

Cheers! Enjoy your fountain!