Introduction: Spider Pumpkins - Arachnophobia Jack O' Lanterns

About: Hi, I'm a Maker of things. I'm interested in almost anything Science, Technology, Engineering, Art, and Math.

In this instructable I make giant Halloween spiders-pumpkins from scrap rebar. These Arachnophobia inducing Jack O' Lanterns are modeled after the anatomy of Black Widow spiders.


    • 3/4" round stock
    • 3/8” rebar
    • 1/2” rebar
    • 5/8” rebar
    • steel ball bearings


Step 1: Drawing, Measuring, and Cutting the Parts

I referenced several images and pulled measurements to get the most life-like leg and leg segment to body (cephalothorax) and abdomen ratios. I then drew a rough sketch of the shape and layout of the Spiders.

I then cut and bent all of the rebar spider parts. I have a spreadsheet calculator that helps with the rough ratios so the body parts will have the correct proportions. I'll try to make the spreadsheet available for anyone that wants to make a spider pumpkin.

Step 2: Making the Fangs

I used a piece of 1/4" steel dowel to make the fangs. I chucked it into my drill press and carefully ground it to a point. I then heated the points an bent them on my anvil. After they cooled I cut them to the correct size.

Step 3: Assembling and Welding the Spider's Legs

I started assembling the body of the spider and added the largest diameter round stock. I then went on to welding the legs. This process is more art than design. You have to play with the angles of the leg sections to make it look the way you like. As I welded each leg I laid it on the sketch to keep track of the location.

Step 4: Welding the Fangs and Final Assembly

I then tacked the two ball bearing together and added the 1/4" bent fangs. After that I could move on to final assembly. I found it useful to have a chuck of steel to prop up the spider parts during welding. I added two spikes to the rear of the spider body to impale and hold the larger pumpkin that will eventually be the abdomen.

Step 5: Adding the Pumpkins to Make the Illusion Complete

This is the fun part! Picking the pumpkins and displaying the spiders!

Pumpkin Challenge

First Prize in the
Pumpkin Challenge