Skeleton Arm, Made by Penguin Manufacturing




Welded sculpture of a human arm.

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Step 1: Tools

  • MIG welder with Argon/CO2 75/25
  • Plasma cutter,(Or anything to cut steel Plasma Cutter is preferred)
  • Bench grinder
  • Angle grinder
  • MIG pliers
  • Wire brush
  • Safety gear: Leather gloves, jacket, welding hood, safety goggles.

Step 2: Materials

From left to right...

  • 3/8 in. all thread bolt, 9 in. long (16 TPI) 1x
  • 3/8 in. all thread bolt, 8 1/2 in. long (16 TPI) 1x
  • 1/4 in. 3 in. long hex-bolt (20 TPI) 4x
  • 5/16 in. 2 in. long hex-bolt (24 TPI) 2x
  • 5/16 in. 1 1/2 in. long hex-bolt (24 TPI) 12x
  • 5/16 in. 1/2 in. long hex-bolt (24TPI) 1x
  • 5 in wide, 6 in long U-channel (5mm)
  • 1/2 in. nut 9x

Step 3: Make a Base

Cut U-channel into a roughly 5' by 6' block for the base of the structure.

Grind with angle grinder to get a smoother non-rusted surface.

Step 4: Make Ulna and Radius.

Grind 45 degree angles into both all thread bolts to make "ulna" and "radius" bones.

Step 5: Ready to Weld!

I found the optimum voltage for this project to be 20 volts.

Step 6: Tack, Tack, and More Tack.

Arrange the pieces as shown.

Tack weld the ulna and radius angle side down.

Weld the nuts on as wrist bones.

Tack weld the rest of the bones on piece by piece as shown until you have a skeleton arm!

Step 7: Cleaning

After welding it all together take your wire brush and brush off any residue, (from welding zinc).

Use an angle grinder to clean welds up, and you're done!

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    8 Discussions


    4 years ago

    Nice job! I mad a couple hands last year out of old sockets, now I've got to get around to making the rest of the body

    photo-2015-02-26, 5:47 PM.jpgphoto-2015-02-26, 5:47 PM.jpgphoto-2015-02-26, 5:47 PM.jpgphoto-2015-02-26, 5:47 PM.jpg
    2 replies

    I have wanted to make a full skeleton since I got the idea of making a hand. Probs gonna be my next project. ( ͡° ͜ʖ ͡°)


    4 years ago on Introduction

    Good one!

    If those bolts are coated, plated, or galvanized though you'd better use a respirator too. Not stuff you want to breath!

    Had a woman in one of my Sculpture classes that made armatures this way for life-size clay figures, made a mold and hollow plaster cast, broke the casting up, then mounted (most of) the pieces on the armature, which had acquired a deep rust patina by then. Nuts and bolts were a whole lot cheaper then though.


    4 years ago on Introduction

    Your sculpture turned out really nice. Thanks for sharing! I hope we see more from you in the future!

    1 reply

    I love this! Simple yet very much like a skeleton at the same time. Really really cool!