Stage 1 Research

Using the internet, suitable reference material for designing and modelling the helmet in 3D was found. This included movie posters, movie stills, photos and images of toys and helmets created by others.

Stage 2 Creating Reference Curves

Although many people work with background images for use as reference when modelling in their 3D programs, I tend to use imported reference curves.

Using the images collected from Stage 1, the main orthographic views (views without perspective – front, side, back etc.) were sketched up in Illustrator. These lines (curves) can then be imported directly into the 3D program being used for modelling (Maya, 3DSMax, Cinema4D etc.), placing the front and side views on their respective planes.

Although these curves will need to be modified and rebuilt in the 3D program, they can be used as an accurate framework from which to begin modelling.

Stage 3 3D Modelling and .STL File Creation

Using the imported Illustrator curves, the helmet was modelled using NURBs. In this instance NURBs modelling was more efficient than using Polygons as we were already working with curves, and the finished model needed to be exported as an .iges file (referencing surface information) for import into 3D CAD software for further manipulation.

Once imported into a 3D CAD program (SolidWorks, ProE, Catia, FreeCAD etc.) the 3D model can be scaled and divided into multiple parts to facilitate 3D printing. Each part was then exported as an .STL mesh suitable for 3D printing software. These files can be downloaded here.

Stage 4 Preparing (Slicing) the 3D Model for Printing

Using 3D printing / slicing software (Repetier, Pronterface, Cura / Slic3r or Skeinforge etc.) each piece of the model was scaled to the desired size and sliced into layers for 3D printing.

The reasoning behind cutting the model into several parts instead of printing out just one large part is as follows:

I wanted to create a large wearable helmet (~ 19 cm x 26 cm x 22 cm), and although I have access to a printer with a large print area, printing in one piece would have taken in excess of 35 hours. Having around 4 years of experience with FDM printing I know that many things can go wrong in that time! (warping, separating layers, collapsed thin walls… the list goes on, but that’s for another topic discussion).

Having many smaller parts instead of one large one means that each piece is more manageable to print. If a print does fail you only lose a few of hours work and a much smaller amount of plastic. Also, not everyone has a printer with a large printable area. Splitting the model into smaller pieces adds flexibility as the pieces can be tailored to each printer’s capabilities.

Separating the model into several parts also allows each part to be optimized for printing. You only need to print supports for areas of the model that need it, not all over the model, wasting time and plastic.

Due to the accuracy of most 3D printers it is easy to align and assemble all the parts together after they are printed.

Stage 5 3D Printing the Parts

For reference, the print settings used to print this model are shown below:
The print was made using a Leapfrog Creatr 3D printer.
(Please note these settings are only a guide and provide a good starting point, but may, and probably will, vary from 3D printer to 3D printer.)

Layer height: 0.35mm – A fairly coarse resolution was chosen to keep printing times down. Also post production on the model after printing (sanding, painting etc.) negates the need for a higher resolution. Having said that, if you have the patience, go for it and print at high res.

Perimeters: 2 – This setting worked fine for me, but go with what best suits your 3D printer.

Infill: 40% - You can probably go lower to save material, but this setting is a good compromise between mechanical integrity and material usage.

Material used: ABS - I prefer working with ABS on larger models, as parts can easily be joined together using ABS glue (a mixture of ABS and acetone, more info below). ABS also offers more post production options such as sanding and painting.

Print head temperature: 220ºC
Printer bed temperature: 90ºC
(Obviously check the material manufacturer’s recommended temperatures.)

Depending on your 3D printer, you may need to use a brim for improved print adhesion to the printer bed.

Time to print!

Print off each of the parts of the helmet. Each part number refers to the layer that part is from the base. For example, part1back.stl will be the back piece of the first layer of the model. See reference diagram for part location.

Several hours later...

Stage 6 Attaching the Printed Parts

As mentioned, for this project the parts were printed off in ABS, and therefore ABS glue can be used to join them together. My recipe for ABS glue is equal volumes of ABS (I usually use scraps from printed supports / brims / failed prints) to acetone.

Note: Acetone is dangerous. Only use in well ventilated areas and better still use with a suitable respirator. Acetone is also highly flammable.

Use a glass jar and mix the ABS and acetone with a metal or wooden stick. Cover and leave the jar for a couple of hours to allow the acetone to dissolve the ABS. Stir well until you have the consistency of white PVA wood glue. Spread this glue on the edges of the model to be joined and push the 2 parts together. Wipe away any excess glue and hold firmly in place for about 5 minutes. Set aside to fully harden. The joint can now be filed or sanded down. Repeat until all the parts have been joined.

If you have chosen to print in PLA or another material, you will have to use another bonding agent specifically suited to that material to stick the parts together.

Stage 7 Preparing for Paint

Sand down the assembled model using progressively finer graded (wet and dry) sand paper. Clean the surface of any dust and grease with a soft wet cloth.

Stage 8 Primer

Spray on a couple of coats of primer following the manufactuerer’s instructions. Allow the model to completely dry. This may require up to 24 hours.

Stage 9 Black Base Coat

Spray on a couple of layers of matt black paint (general use hardware store spray paint is fine for this). Allow to fully dry. Sand down using fine sand paper to intensify the matt effect.

Stage 10 Adding Metallics and Details

Spray on a thin layer of metallic grey / silver paint. You may have to hold the spray further away from the model in order not to overdo the metal effect. You don’t need much, just a thin speckled layering that allows the black to show through giving the impression of metal.

To add more character to the helmet, scratches and damage were added using a Dremel.

Highlight areas were gently airbrushed in using steel coloured acrylic paint. Finer details (e.g. around sharp edges) were then painted in using a fine brush.

To protect the paint work, the helmet was sprayed with a couple of coats of clear matt acrylic varnish and allowed to dry.

You now have a cool looking Batman helmet!

But wait, "what about the glowing eyes?" I hear you ask...

Stage 11 LED Glowing Eyes!

To finish off the helmet, a couple of pieces of translucent plastic (cut from an old microwave dish cover) were added behind the eye slots.

RGB LED strip was stuck inside the helmet. Most LED strips allow you to change the colour of the lighting allowing you to change Batman’s mood! (I don't recommend using the LEDs while wearing the helmet as you'll probably go blind!)