Last year I set out to make both Daft Punk helmets starting at the end of September. I wanted to make them as high quality as possible, with electronics, without spending too much money, and only had a month to do it in time for Halloween.
Most of the quality DIY helmets online took months to build - for each one. Is it possible to make two with acceptable quality in one month? SPOILER - yes it is, with one caveat - I had a friend build the electronics for the Guy Manuel (gold) helmet.
Be forewarned, this is a big project! I would recommend making one of the two to make it a little less challenging. The silver Thomas helmet is a little easier because it does not require a vacuum formed visor.
Technologies & Techniques Covered
- 3D printing
- Vacuum forming, including building your own vacuum former
- Epoxy resin
- Class-A finishing
- Electronics, including Arduino and Parallax microcontrollers
- Did I mention sanding?
Step 1: Helmet Shell Assembly
- 3D models of Thomas Helmet by Ben Diger (1.5 version)
- 3D model of Guy Manuel Helmet by Ben Diger (1.5 version)
- 3D Printer with 6x6x6 build platform and heated bed (Printrbot Simple Metal is what I used)
- 2 kg Filament (ABS)
- Lots of zip ties!
- Sandpaper 100 grit (foam sandpaper blocks from Harbor Freight work well)
- Acetone for gluing ABS or epoxy if you use PLA or other materials (possibly optional)
- Small clamps (optional)
- Beer: Swami's IPA
Ben Diger made some excellent, easy to assemble 3D models and posted them over at Thingiverse. They were the most authentic-looking downloadable models I could find. As the helmets are too big to print in one piece they are divided up into a couple dozen pieces and are assembled with zip ties.
Although they are well designed, they aren't set up to be easily printed. You will have to maneuver them around and create supports so that they will print well. It took about a week to print all the parts for both helmets; a little longer if you include the vacuum-form molds.
Once printed the parts need to be cleaned up a bit with a file or sand paper so they fit together cleanly. They can then be assembled with glue, acetone (for ABS), or just zip ties. I used zip ties and acetone, although the zip ties alone may have been fine, especially if you are putting an optional epoxy coating over the helmets.
Step 2: Vacuum Form Mold for the Visor
Also included with Ben Diger's 3D models is a mold for vacuum forming the tinted visor for the gold Guy-Manuel helmet. These parts need to be printed, zip tied, reinforce the backside, and Bondo the top for a smooth finish. More on vacuum forming later.
In finishing the mold, I read about a promising trick that I wasn't able to try. Apparently PETG doesn't stick to itself at the temperatures used for vacuum forming, so the idea is to form a thin sheet of PETG over the mold and leave it there. Then trim it back and mold your work pieces over the PETG-coated mold.
Step 3: Epoxy Coating the Shells - Optional
- 2 part Epoxy resin (slow hardener)
- Fumed Silica epoxy thickener
- Disposable brushes for applying epoxy
- Paint stir sticks
- Eye protection
- Nitrile/rubber gloves
- Ventilated work area
- Do not work with epoxy or Bondo indoors without very good ventilation. The odors are strong. ALWAYS wear a respirator and eye protection when working with fumed silica or sanding Bondo.
After the fact I found that using the epoxy resin was probably optional, although it did make the helmets virtually indestructible. If you aren't going to use epoxy, skip to the next step.
The original plan was to coat the helmets with epoxy resin and sand the resin down to a smooth finish, then paint. That turned out to be naive - epoxy becomes incredibly hard when it cures! I tried sanding it with a power sander, but the sandpaper lost that battle.
The epoxy resin I used was West System 105 resin and 206 slow hardener. It is expensive stuff, I chose it because I thought it was going to be the final coating before prime & paint. If you decide to epoxy your project for strength you can probably use something much cheaper.
Be sure to mix the correct epoxy/hardener ratio according to the instructions, and add fumed silica until it is thick enough to bridge gaps when applied, stirring the whole time. Apply with a brush that you don't like, it will be hard as a rock when the epoxy cures.
Step 4: Bondo-ing
- Bondo spreader tools
- Paint stir sticks
- Nitrile/rubber gloves
- Ventilated work area
- Orbital sander (highly recommended) & sandpaper 100, 220 grits
- Water basin for rinsing
- Do not work with epoxy or Bondo indoors without very good ventilation.
The odors are strong. ALWAYS wear a respirator and eye protection when working with fumed silica or sanding Bondo.
I've never worked with Bondo before; turns out the stuff is awesome, if a little bit of a pain to apply. The ability to shape it and polish it to a smooth glossy finish is what makes it great. Check out this video on how to work with it:
It cures very fast, and sticks to everything. But you learn fast how to get good results. Apply in batches, let cure, sand, and rinse. Repeat to fill voids until you have a smooth, shaped surface.
Step 5: Sanding & Priming
- Sandpaper - 320, 500, 1000 grits, wet/dry. Gotta love Harbor Freight!
- Orbital sander - highly recommended
- Rust-oleum 2-in-1 Filler & Sandable Primer (wish I would have found this stuff earlier, works much better for this project than regular sandable primer). Get 2 cans just in case.
- Bondo Spot Putty (optional - you can also use regular Bondo)
- Water basin for rinsing
- Eye protection
Once you are happy with the shape and all holes and voids are filled, it's time for finish sanding.
Dry sand with 320 sandpaper to remove scratches and smooth over rough areas. Whether using an orbital sander or hand-sanding, use circular motions while constantly moving to prevent flat spots. It's not as hard as it sounds, and fun to 'sculpt' the part as you go.
Rinse, dry, and sand with 500 grit.
Rinse again and wet-sand with 1000 grit sandpaper. This part is rewarding - you will end up with a glassy smooth surface.
I tried several primers before I found the best option - Rust-oleum 2-in-1 Filler & Sandable Primer. The 'filler' part fixes a lot of little imperfections, but will also fill in fine details so you might not want to use it on the faux circuit board beneath the ear cylinders.
The primer will highlight larger imperfections. Once it dries, fill these areas with Bondo Spot Putty or regular Bondo. Let it cure, then sand again with 500 and 1000 grit.
Rinse, dry, and apply (hopefully) the last coat of primer. Once it dries, time for the final polish.
Step 6: Final Polish and Painting
OK time to get excited! The hardest part is done, and the helmets are starting to look really good.
- Wet & Dry sandpaper sheets, 1000 and/or 2000 grit
- Water basin for rinsing
- Krylon Foil Metallic spray paint, 1 can each gold & silver
For the final polish, wet sand the primer with 2000 grit wet/dry sandpaper. You may need to go to an auto parts store to find grits greater than 1000. Rinse with fresh water and let dry completely.
We tried several different gold and silver spray paints and found there was a wide difference in what manufacturers considered a 'metallic' finish. Brands that said chrome metallic were more of a shiny gray with sparkly specs, and several weren't shiny at all. The winner was Krylon Foil Metallic, which was about as close as you can get to the desired finish without spending $500 on professional chrome plating.
At this point it's crunch time, only a couple of days until Halloween. We didn't get the last coat of paint on until Halloween day, which is inadvisable. The helmets looked good, but picked up fingerprints easily. It would probably have helped to give it 24 hours to completely dry.
Step 7: Building a Vacuum Former
- Shop Vac or vacuum with hose
- Saw to cut plywood & 1"x4"s (rotary saw works well)
- Drill / power screwdriver
- Hole saw - for cutting hole in plywood to insert vacuum tube
- Plywood, 3/4" thick (other thickness might work), 1/2 sheet will be more than enough
- Pegboard, or plywood drilled with lots of holes
- Foil tape
- 1"x4" board, about 7 feet long, for frame
- Your kitchen oven
- Wood glue (optional)
- Caulk (possibly optional)
- 3D printed adapter for connecting vacuum hose to box (optional)
To make the gold Guy Manuel visor, we are going to build a vacuum former. It's relatively easy, inexpensive, and doesn't take up much space when stored.
How it Works
Vacuum forming works by heating a sheet of plastic up until it's very pliable, placing the plastic over a mold on top of a vacuum platen, and applying vacuum. The vacuum pulls the hot plastic down to conform to the mold. Here's a video on how it works:
Building the Vacuum Former
The vacuum former base should be larger than the mold, but the length & width needs to fit inside your oven. For my particular design, it should be tall enough to be able to attach the vacuum hose in the side.
Use the hole saw to drill a hole for the vacuum to attach to. The hole should form a good seal around the vacuum hose. If you aren't able to 3D print an adapter, the foil tape can be used to form a seal.
Assemble the bottom and 4 sides of the vacuum chamber box with glue and screws. Optionally, caulk the joints inside the box. Use the box as a template to mark the pegboard sheet.
Cut the pegboard sheet. Attached pegboard with foil tape to the top of the box. Seal all other outside joints with the foil tape.
Building the Frame
The frame will hold the plastic as it heats up in the oven, and will keep it in place as the plastic is drawn around the mold. There are various ways to make a frame. I simply used 1x4s to make a rectangle.
The frame should be the same length and width as the vacuum form box. Cut the 1x4s and screw them together to form a rectangle as in the pictures.
Step 8: Vacuum Forming the Visor
- PETG Sheet, 1/16" thick, 24"x24", 2-3 sheets because you'll probably mess up a few visors
- Tin snips, box cutter, or ? for cutting PETG sheet
- Stapler for attaching PETG to frame
- Oven mitts
I searched for pre-tinted PETG sheet but it wasn't available except for custom order (thousands of dollars). Instead we were going to have to shape and then tint. I cut a strip of about 6" off one side of the 24x24 sheets of PETG to be used for the visor for the silver helmet, leaving an 18x24" sheet. Cutting that in half left two 18x12 sheets to form two visors for the gold helmet.
The key to getting a good parts is to heat the plastic to the right temperature. We weren't able to directly measure the temp, so we had to go off of the visible clues. That is, how much the plastic sags as it is heated. For this size frame and thickness of PETG, I found that about 4 inches or more was about what we wanted. Since the frame is only 4" tall, more than that would require blocks to hold the frame away from the oven racks.
This video shows the early stages of the plastic sagging:
Vacuum Forming the Visor
Cut out a sheet of PETG to fit the frame. Use a stapler or other means to attach the plastic securely to the frame. Move the oven rack up so that the frame will be about 4-6 inches below it.
Center the mold on the vacuum forming box on a counter near the oven. I found, after a few tries, that this mold works better if it is elevated a little bit. Use shims or whatever you have handy to raise the mold up about 1/4" to 1/2" off the vacuum forming box.
Attach the vacuum and turn on the broiler in the oven. Allow the oven to preheat for about 5 minutes and put on the oven mitts.
Timing is key here:
- Place the frame, plastic side up, under the broiler
- Watch closely as the PETG will start to sag. Wait until it's almost touching the oven rack.
- Turn on the vacuum
- With oven mitts, pull the frame out of the oven, flip it over, and press it straight down over the mold
- Allow to cool for a few seconds
- Turn off the vacuum
You will want to make several of the visors, there are plenty of ways to screw them up in the next steps...
Video of forming process (early attempt without shims):
You can now vacuum form parts with your own former. High five.
Step 9: Tinting the Visor - Dye Method
This method for tinting the visor didn't work for me as I used the wrong dye, but theoretically the results are great if you do it right. To skip to what I ended up doing go to the next step.
- iDyePoly fabric dye
- Candy thermometer
- Pre-formed visors
- 5-gallon pot
- Rinse basin
- Dropcloth - cover everything, dye is hard to get out!
- Nitrile gloves
Wear clothes you don't care about.
This method should be the best way to do it, however, as I learned later, RIT doesn't work for PETG. I have heard that iDyePoly (not the regular iDye) will work and I may try that if I redo the visors.
This video explains the whole process very well, I wish I had seen it before:
Step 10: Tinting the Visor - Success (sort Of)
After failing with the dye method, other options were considered. Having a local auto tinting shop do it was tempting, but the ease of spray-on tint was pretty attractive. I ordered some VHT Nite-Shades taillight tinting spray and tried it out.
Spraying the back side with 2-4 coats achieved about the right amount of tint. Be very careful to use a steady, nonstop motion to avoid uneven coating. Don't touch it until it is completely dry or it will smear. Try it out on a scrap piece first to get the hang of it. And wear a mask, WOW does this stuff stink.
Overall I wouldn't recommend this method. Up close you can see the little dots of black, and it's difficult to see out of, especially at night.
Step 11: Trimming the Visors
- Formed, tinted visors
- Tin snips
- Dremel with rotary sanding wheel
- Box cutter
Trimming the PETG Visors
I tried a few ways to trim the visors to their final form and found the best for each visor.
The visor for the silver Thomas helmet has simple, straight lines and angles. The best tools to cut it to shape were a box cutter and a straightedge.
The compound curves of the gold visor made it a bit more complicated. I tried a Dremel VersaTip hot knife, which worked tolerably well, but found the best way was to trim closely with tin snips and sand the last bit down with a rotary Dremel sanding wheel. The sanding wheel gave a very nice edge with a finished look.
The back of the gold helmet features exposed wiring. Not much to this step, simply double sided tape and scrap wire. Make sure you use fine gauge wire; the larger stuff gets heavy fast.
Step 12: Silver Thomas Helmet Scrolling Marquee LED (Controlled by Smartphone Via Bluetooth)
- Adafruit Trinket Pro 5v $10
- HC-05 Bluetooth Module $6
- MAX7219 LED Matrix (4 linked together) x2 $16
- USB Battery $16 (or any battery with the correct voltage)
- USB Micro Breakout board $1.50 (upgrade from my original build, not pictured)
- USB to Micro USB Cable (you probably already have one, these are the most common USB cables out there. Used to charge most Android phones)
- Vero Board (or other prototyping PCB)
- Soldering iron, solder, flux
- Bluetooth SPP app to send text and control the LED display
The goal for this part of the build is to create a scrolling LED marquee that is programmable from a cell phone via Bluetooth. Being able to write a message to the visor on the fly would better enable me to anger friends and neighbors with disparaging remarks about their favorite sports teams.
I would have liked a more authentic LED matrix, but that would take a lot of time that I didn't have. The compromise was to use MAX7219 LED matrix squares. They are 8x8 LED matrices and are daisy chain-able. I could use a Arduino controller (Adafruit Trinket Pro) and send commands to it via an add-on Bluetooth module (HC-05). To power the whole thing (and the ear LEDs in the next step), I re-purposed a USB cell phone charging battery pack.
I adapted the directions on this site to create the display:
Here's anther similar one:
I won't go into depth on this step as all the info is in those two websites, and this Instructable is long enough already!
The visor required a curved LED marquee instead of straight, so I broke each 8x8 unit apart and wired them together. The circuit boards they are mounted to are made to be easily cut apart. The newly separated matrices were then mounted to a custom 3D printed frame that can be epoxied into the visor. If you get this far and are interested in the frames, send me a message and I'll send you the stl files for 3D printing.
To house the Trinket & Bluetooth module, I created a 3D printed 'puck' that goes into the earpieces.
Testing the LEDs:
Final test before assembly:
Once everything is wired up correctly, the Bluetooth SPP app can connect to the setup to send text from your phone that will read out on the display. It also enables you to create preset phrases, change the speed of scrolling, and adjust the brightness.
Step 13: Silver Thomas Helmet Ear LEDs
- Adafruit Trinket 5v $7
- WS2812b Addressable RGB LEDs 60 per meter in waterproof casing $24
- Battery (one battery pack for all the electronics; see scrolling marquee)
- Soldering equipment
- Electrical tape
In addition to the scrolling LED display I also wanted LEDs for the ear light rings. With more time both probably could have been done with one microcontroller. The Trinkets are cheap, so why not use one for each feature?
I decided on WS2812b LEDs as they are RGB and fully addressable with only 3 wires. This website explains them well.
This build was very easy:
- Cut LED strips to length
- Solder wires onto LED strips (hardest part)
- Connect LED strips to Trinket and power
- Connect Trinket to power
- Load Adafruit Neopixel demo sketch onto Trinket
- Edit code to get just the LED sequences you like (optional)
- Power it up
Note that the earpiece light rings that the LED strips went into are customized versions of the ones Ben Diger created, printed in a translucent PETG filament. Optionally, you can cut out acrylic disks and glue the LED strips in place.
Testing the light rings:
Step 14: Gold Guy-Manuel Electronics
Goal for the electronics:
- 3 modes for light bars, selectable via rotary encoder:
- Preset patterns - dropping blocks, etc
- VU meter - Starting at the bottom, lights 'rise' with volume of music/noise
- Graphic equalizer / spectrum analyzer - each of the 8 bars reflect a frequency. Loudness of that frequency determines how many LEDs in the corresponding bar light up
Materials (partial list)
- WS2812b LED strip, 60/meter, cut up into strips of 4 LEDs and wired together, mounted in light bars
- Rotary Encoder with RGB LED illumination
- Microcontroller (Parallax Propeller was what my friend used for this build)
- Microphone & preamp
- MSGEQ7 Graphic Equalizer chip for building with microphone, or the chip + breakout board for line input
- Draft film diffuser paper to cover the LEDs.
- Lots more misc electronics parts
- Gaffer tape (seriously, that stuff is awesome)
Due to the limited time, I enlisted the help of a friend to design and build the electronics for the gold helmet. This section won't have much detail, unless I can convince him to spend even more of his time helping me and doing a writeup! He is a Parallax enthusiast, and built the entire system using a Parallax microcontroller. Although more expensive than Arduino, they are much more powerful at 32 bits with 8 cores to the typical Arduino's one.
The three modes for the light bars (preset patterns, VU meter, and graphic eq) are selectable via a rotary encoder mounted on the side of the helmet. The encoder has a built-in RGB LED, so it was programmed to light up with a color that indicated what mode it was in.
We used 60/meter density LEDs. 144/meter were available, but the 60 density were already very bright. More would also take a lot of extra power and drain the battery faster.
The VU meter was programmed to have a very faint glow from all the bars when the bars aren't active (no noise), with one side glowing blue and the other red.
In the end, everything worked great except the graphic eq. It was buggy, and we ran out of time to program it. The other two modes were a hit though
Step 15: Finishing Touches
- Egg crate foam or foam blocks for inside padding
- Gaffer tape - expensive but worth it, for this project and many other applications.
- Hot glue gun
- Foam double-sided tape, black
I didn't get any pictures of installing the foam padding, but it's pretty straightforward. Cut pieces of egg crate or block foam and use hot glue to attach them inside the helmet. Don't use pieces of foam that are too large and restrict airflow or it will get really hot inside.
Use the gaffer tape to control any stray wires and attach any loose pieces inside. Use the double sided tape to affix the battery inside the helmet. I put the battery in the silver helmet at the back so it would counterbalance the heavy visor in front.
Step 16: Done!
- Beer: Dr. Jekyll's Bio Beer Spiced IPA
- Halloween Candy
I really enjoyed this project. Working with all the technologies and techniques was educational, and the end result exceeded expectations. Plus, they are great conversation pieces on a table running their light show.
Good luck with your build, and if you do build one, please post it in the comments!