Intro: Displacing Water: Archimedes Screw Mk.IV
In my high school's Industrial Materials class my friend and I use materials and tools provided to us to solve problems. Our teacher Mr. Eberts is a huge fan of Da Vinci and his inventions. He gave us a list of Da Vinci's machines and we decided to try and recreate the Archimedes Screw with some of our own modifications. Because little or no recorded specifications were given to his inventions, our goal was to recreate them the best that we could by what we had seen and logically felt would make it work.
Da Vinci's modifications to the Archimedes screw were to use pipes with a certain number of spirals instead of a hollow cylinder and a rotating inclined plane inside. An unnamed inventor added the frame to this device and finally, my friend and I added gears to improve efficiency and a box to be able to test this without having to travel to a body of water. The above image is our concept; however, the spirals we did not draw on this computer model because more time would have been wasted drawing them instead of getting to work on it in class.
Step 1: Timeline
This is to get an idea of how long such a project might take!
Price: Area of the whole thing is in the range of 2400-2800 in^2. It may be approaching $120; check your local HD or Lowe’s!
Step 2: Materials Part 1
Complete measurements use LWH
• Base: 2 pieces of 36” x ¾” x ¾”
• Height: 2 pieces of ¾” x ¾” x 37”
• Horizontal supports: 5 pieces for base, 1 to support height pieces. All 12” x ¾” x ¾”
o The piece to support the height pieces is 15” from the ground!
• Vertical supports: 2 pieces of ¾” x ¾” x 15”
o One of their sides is cut 40 degrees to fit the 40 degrees hypotenuse! You can also use the hypotenuse as a reference of where to cut if you do not have a protractor.
• Diagonal supports: 2 pieces of 22” x ¾” x ¾”
o One of their sides is cut 60 degrees to adjacently fit diagonally! You can also use the base as a reference of where to cut if you do not have a protractor.
Step 3: Materials Part 2
• Large board of 30.5” x 12” x ¾”
o Ours was pieced together from junk wood, but if you have a solid piece, that’ll be perfect!
• Screw rotational support of 5 ½” x ¾” x 10 ¾” and a half circle cut off with a radius of 1.5”
o If you do not want a platform to align the gears precisely, then the screw rotational support should be 5 ½” x ¾” x 11”
o We used a platform of ¼” to raise the screw to align properly, but the option above saves a minute.
Ours is way over-the-top since we just used a mechanism from trial runs, but you could make any cup/small box you desire.
Step 4: Materials Part 3
• The hollow cylinder is 4” long then cut 40 degrees from the horizontal. Its outer diameter is 2 ½” and inner diameter is 1”.
• The small tube is a 3 ¾” cylinder of diameter slightly smaller than 1".
o One side’s diameter should be slightly smaller to prevent jams inside the screw.
• 2 pieces of 9 ¼” x ¾” x 6”
• 2 pieces of 11.5” x ¾” x 6”
Step 5: Materials Part 4
• Drive Cylinder of 9 ½” length and 3” diameter
• Rectangle of 12” x ¾” x 6” and 3” diameter
o We separated the rectangle in half, cut half-circles, and connected them with metal, but if you can make a 3” diameter circle easier, then go for it!
• 2 squares of 4” x ¾” x 4”
• 8 pins of 2” length and 7/16” diameter
Gears and crank wheel
• 3 wooden wheels of 9 ¾” diameter and 1 ¼” thick
o 2 of these wheels are the gears; the remaining one is your wheel to rotate the screw with
o The gears have 16 teeth
Step 6: Materials Part 5
Armor and Screw
• Strong side supports that strengthen horizontal stability greatly of 12 ¼” x 1” x 29 ¾”, cut to shape with the frame
• Straight long cylinder with 1.5” radius. 34” + (more is better in case of errors!)
Step 7: Tools
• Precise saws and protractor/ saws with adjustable angle
• Metal cutter
• Drill press
o 7/16” bit for the gear / gear mount holes
o 3/8” bit for making metal brackets if going that route
• Drill (1” bit for hollowing out screw)
Step 8: Construction: Frame
1. Constructing the frame first is highly recommended. Not only is it obviously essential to align the rest of the material, but it can be your reference to fall back on in case of human/machine errors.
2. Nail the vertical supports at the hypotenuse’s halfway point.
3. Move around the diagonal supports until they fit perfectly. Nail when ready to get good vertical strength for the frame
4. Separate the base horizontal supports at equal distances from each other. The middle base horizontal support should be aligned with the vertical support.
5. 15” from the ground, nail the horizontal support that prevents the tall vertical sticks from collapsing inward.
6. Nail the frame onto a thick and heavy single wooden base.
7. Nail armor onto sides for a resilient frame.
Step 9: Construction: Gears
1. Carve out 2 of the wooden wheels using rasps. Each gear should have 16 triangular teeth. If a tooth is too curved and its adjacent is triangular, there is a possibility of jamming. You will be like Arnold Schwarzenegger after this.
[One of the pictures has a smaller model gear but the same principles apply.]
Step 10: Construction: Spine
1. A solid board is ideal for the spine, but you can see we attached used pieces of wood together to create the large spine. As it turns out, the attachment points are great places to put the cup to catch the water with, but with a solid board you have the advantage of choosing where the cup goes later.
2. You can set the spine inside the frame, letting the top of it rest on the raised horizontal support 15” off the ground and the bottom rested on the last base horizontal support. It does not need to be nailed yet, but it does provide good horizontal strength while you work on other parts.
3. Construct the rotational support with or without the platform but do not mount yet. Until the screw’s degree is placed correctly, its position should not be permanent.
Step 11: Construction: Brackets, Pins, and Gears
1. Construct the rectangular mount by either procedures below and nail 6.25”distance from the top.
a. Having two separate rectangles with a half circle of radius 1.5” cut out on each and then combining them together using metal strips with holes drilled through to screw in.
b. Having a single rectangle with a circle of radius 1.5” cut out.
2. Cut 7/16” diameter dowel rods into 8 2” pins. These will hold the gears in place with their braces and allow them to spin without falling off.
3. Construct 2 square mounts (for both gears) of 4” by 4”. These squares and your gears need evenly spaced holes for the pins! Also the 4 holes should be far enough so that the screw tube and the tube connected to the crank wheel can fit [circle inside square].
a. We had evenly spaced holes on our gears already, and so we just aligned our square mounts’ holes.
b. If you do not, try to center the square mount with the gear’s center. They need to be center to have correct circular movement while spinning.
4. Nail one of these square mounts to the 3” drive cylinder. Place this cylinder inside the rectangular mount.
5. Try rotating the drive cylinder. If it moves smoothly then good job! You may now connect one of the gears with the square mount using 4 pins. If not, you may need to sand down the mount’s circle and the cylinder.
Step 12: Construction: Screw, Screw Mount, Rotation
1. A 4” diameter cylinder needs to be cut 40 degrees from the horizontal. The end result should point towards the back top gear. This should be screwed into the heavy base.
2. A 3 ¾” cylinder of diameter slightly less than 1” falls into the newly cut slanted cylinder. It should be sanded down slightly until it can rotate without significant friction.
3. Cut a stable solid tube of 1.5” radius to 34” length and nail one of the square gear mounts onto it. Remember to center it to have correct circular motion. This long tube is the primary screw that brings the water upward.
4. Hollow out the bottom of the screw 2” deep so that the 3 ¾” cylinder inside the cylinder mount can also go into the screw, connecting the two parts together and allowing rotational movement of the screw.
5. Twist piping around the screw until you reach the desired height (or until you run out of piping). This piping will scoop up water from the bottom and carry it to the top. We attached the piping by trapping the beginning and end using bent nails...
Step 13: Construction: Box and Flood Containment
1. Construct a box around the bottom of the screw for water to be contained in. Its dimensions are not crucial so long as the piping can still reach water and the screw does not grind against it.
2. To prevent major flooding that ruins the project as well as your floors and other things you must glue all potential areas water might escape from. Also polyurethane the box, frame, and base areas water might touch. Don’t polyurethane any other pieces just yet because if you get to assembly and those parts need sanding down and other adjustments, the polyurethane will just create more work.
Step 14: Construction: Assembly!
1. Nail your remaining wooden wheel to the cylinder tube at the top that goes through the rectangular mount and connects with the top gear and its square mount.
2. You may now permanently nail the spine onto the frame, creating more stability while the screw is rotating.
3. Connect your second gear with the square mount on the screw itself using 4 pins. Place your rotational support on the spine and carefully rest the screw on the top gear. Once you’ve seen where it naturally rests, mark where the rotational support should be on the spine and glue it on. You can also see where your pipe ends and where your cup needs to be.
4. Test out the smoothness of the gears by rotating the top gear with your crank wheel. If there are jams, you may need to refine your gear teeth again, adjust your rotational support height which affects the angle of the screw, or adjust the top gear’s cylinder further back.
5. Once you are truly sure you have sealed all possible leaks, fill the box with water and crank!
Step 15: Results
As expected, water traveled from the bottom of the screw through the piping and escaped all the way at the top. There were some initial fears that we would have to crank continuously to prevent the water from flowing down the pipe once it reached midway, but it was actually harder to get the water down instead of getting it to travel up!
The slightest of errors such as being 1/16" off, almost unnoticeable mistake in nailing, cracks in the 1/32" range; all of these seemed trivial but the impacts they had were surprising. In the future, we would like to make some areas have less parts to minimize the effects of any errors. This device also should have wheels to move around conveniently.