Lets make a simple hydraulic arm! I designed this simple arm that's powered using syringes as hydraulics.

I've also made a video so make sure to check that out!

What I used-

Platform- I used a round table coaster

Rotating base- I used a tin lid

Arm- 2 large lolly sticks and 4 standard sized lolly stcks

Hydraulics- 6 1ml syringes I acquired from amazon.com

Electro magnet, battery and switch - I got mine from the local electronics store

Nails

After shave bottle lid- used to heighten the arm from the base

Rubber bands

1 Pin

4 Pearler beads

Hot glue!

Step 1: The Platform and Base

For the platform I used a circular table coaster as it was easy to punch pins/ nails in to. Th rotating base of the arm is made from a tin lid which I drilled a hole in the centre. I used a pin and a perler bead (perler bead used as a spacer) to secure the base to the platform allowing it to rotate.

Step 2: Start of the Arm

I used two large lolly sticks and four standard sized sticks. I decided to paint them grey. For the larger lolly sticks I drilled two holes at the end that were 1 inch apart. The holes need to be big enough for a nail to fit through. I also chopped of the bottom of the lager sticks. or the small sticks I drilled two holes at the end that were 1 and a half inches apart and another hole at the other side.

Step 3: Hydraulics and the Arm

I pieced together the first half of the arm as shown using nails and prepared the hydraulics. I used small 1ml syringes as the hydraulics. I attached I perler bead to the top of each hydraulic and a cable tidy to the tubing.

The slots in the perler bead and the cable tidy will allow the hydraulic to move freely. the first hydraulic I glued the cable tidy near the top end of the tube and for the second hydraulic I flipped it over and glued it near the bottom. I then slotted the hydraulics over the nails as shown above. I then pieced together the other lolly sticks on the other half of the arm.

Step 4: Attaching the Arm and Electro Magnet

I simply attached the arm to the rotating base using hot glue. I used a square aftershave lid to give the arm some hight to allow the hydraulic tubing to fit behind the arm. For the lifting device I thought it would be cool to add an electro magnet so I purchased one from the local electronics store. Yo can always make a DIY electro magnet by coiling some wire around a metal screw. I threaded the magnet to the end of the arm and tucked the wires towards the back as shown.

Step 5: Adding the Rotating Hydraulic

I glued a additional wire tidy to the edge of the tin. I prepared another syringe like the others and nailed it to the platform using another perler bead as a spacer. I then coupled the hydraulic to the base using a nail.

Step 6: Completing the Hydraulics and Tweaking

I used three lengths of 3mm tubing to connect the arm to the controller syringes. Filling up the tube with water can be quite tricky. I pulled out the handle of the controller syringe and sucked up water in to the tube and then held my finger over the syringe so the water would stay in the line. I then attached the tube to the arm and then placed the handle back in to the other syringe.

Once all the hydraulics were connected I wired up a battery and small switch to the magnet. I also added rubber bands to the arm as shown to allow a better moment of the arm.