Intro: Soldier 76 Pulse Rifle
This is my second venture into making a large scale wooden prop, although this uses mainly plywood for its construction, rather than the timber beams of my Reach sniper
Based on the gold skin (With some influence from Halo's fuel rod gun) from the Overwatch character Soldier 76, this rifle includes some adaptations that allow certain parts to illuminate or trigger sound with an integrated switch in the trigger mechanism.
I did make a quick costume to match the colour scheme, but the focus of this instructable is mainly on the rifle itself
Step 1: Generating the Template
The 3D files for overwatch models are readily available online. Many people have designed models for Overwatch props from scratch, which yields a cleaner result to work from, but using the Autodesk tool 123D Make, I was able to slice the model to get something to start with. The tool itself could be used in conjunction with a laser cutter, or even use the layers to print and cut out by hand to build the prop entirely from 2D slices, but in this instructable I'll mainly just be using the center slice as a reference.
The middle slice is a good starting point as it contains most of the overall dimensions, so you won't need to refer to the model all the time in order to check relative sizes of each component you're adding on.
The 2 PDFs in this step combine to form the cross section of the prop, and are scaled to make the pulse rifle around 95cm long, which is my best approximation from the concept art. The print outs are for A2 sized paper, so each one should use 4 sheets of A4. When cut out and arranged, they can be stuck to a plywood or MDF sheet so the making can begin.
If measurements of the prop are needed, using a program such as Pepakura Designer to compare the co-ordinates of two vertices will tell you the distance between them so that you can manually draw out cut lines onto your templates.
Step 2: Main Body
The most difficult part of making wooden props like this is planning out how to construct it as easily as possible given the available materials. Prop making is often a compromise between what it accurate to the original specifications, and what looks good, so ignoring some changes in width, or surfaces that are near enough parallel, you can get a much cleaner look.
For example, the foregrip should be almost 10mm wider than the hand grip, but considering the change in width is spread over half the length of the gun, there's no easy way to replicate that angle. Rather than routing in the details for the hand grip, I instead built up the raised sections afterwards and blended the edges in after, allowing it to reach the original thickness. By working with common plywood thicknesses (I used 12mm, 8mm and 3mm) you can replicate around 80-90% of the whole prop's volume using just 5 separate pieces.
Once the template is stuck to the first sheet of ply, use a jigsaw to cut around it as neatly as possible. Take your time, as this will serve as a guide later on. Once finished, drill pilot holes at the far corners of the design (See 2nd image) into additional sheets of plywood, and bolt them together. Use a router with a bearing bit to trace around the shape of the first cross section. A more powerful router may be able to do multiple pieces at a time.
The two outermost pieces do not include the hand grip but does extend the area around the ammo counter, and the tip of the "barrel" varies slightly between each. This means that there are 3 different shapes within these 5 sections, but it took very little time to remedy: When cutting out the barrel, I ignored the original template and extended it to match the profile of the outermost sections so I could remove material later rather than adding on the parts that were missed when replicating the slices, and applied a similar process when cutting around the ammo counter on the outermost pieces.
Depending on how straight the edges are it may be okay to use a router to bevel the edges after assembly (As with the hand grip), or clamp it to the edge of a table and use that as a guide for the router (Preferred method for the top and bottom of the barrels).
Step 3: Extra Side Panels
At this point it's worth mentioning that all assembly is still temporary, and should be done using the bolts and guide holes, since electronics (If applicable) and other components will need to be added later.
There is more variation to the thicknesses of the following parts. The main body of the rifle should be around 50mm (5 sheets of 10mm would be ideal, though mine consisted of a 12mm core with two 8mm layers on either side for a total of 44mm). The base of the rifle and the stock each need an additional layer (I used a small section of 8mm for each), but the strips that run down the length of the barrel are more prominent, so they would require two layers of plywood sandwiched together (Image 2). There is a lot of shallow bevelling to be done here, and potentially freehand routing / engraving. A belt sander would save you a lot of time, but it's well within the realms of possibility to use a wood rasp and a file, then finish it off with a block of wood and sandpaper.
Step 4: Internal Wiring + EL Wire Inverter
The casing for the AA cells that supply power to the inverter and EL wire was slightly wider than the center 3 sheets of ply, so I had to engrave a small section away to allow it to fit.
The EL wire would usually toggle between modes, but by bridging two specific points on the pcb I was able to bypass this (CAT5 for the win!) so that it would always be on as long as there were AA cells installed. This made the activation method much simpler, as I could cut the strip of metal joining the two AA cells, run a wire from each down to a momentary switch behind the trigger and turn the power on and off using that!
In addition to the output from the inverter, I added two more outputs directly from the 0 and +3v of the cells (Before where the springs attached to the PCB. One was planned for a sound module, but later be left disconnected (Explained in the next step), but the other stretched just above the inverter where I connected a blue LED to act as a backlight for the ammo counter.
Now that the pieces were no longer required to be separated, I tested the trigger actuation and the fit of the wires before gluing the 5 sections together permanently.
Step 5: Sound Module
It was my original plan to use the spare cables spliced to the battery pack to power a small USB sound module, but I couldn't get it to work by using the 3v source to turn it on temporarily rather than have it already powered up and activated with a momentary trigger, so I opted to install the sound system as a stand alone unit in the grenade launcher.
I epoxied a cheap rechargeable USB speaker to a circle of wood that was cut to fit inside a section of drain pipe, made a short female-female 3.5mm adapter to move the audio connection to the outside of the drain pipe as well as a mini-B male to micro-B female USB extension (Both made from old parts as I couldn't find the right adapters online). I didn't want to bother with opening up the speaker to move the power switch outside too, so I just drilled a small hole above it to toggle it on/off using a small screwdriver.
While not strictly part of the rifle's design, the method I used for attaching the tube to the wooden body of the rifle was to mount an 8 slot picatinny rail to the rifle with long wood screws, and the corresponding bracket to the plastic tube using 3 small bolts. This makes detaching it much easier if the speaker requires charging, or if I'm able to provide a better implementation for the sound playback trigger.
Step 6: Fitting the EL Wire (Final Assembly)
The EL wire is stretched back and forth 10 times within a 30mm external diameter clear acrylic tube with smaller segments of PVC pipe cut out to form the "rings" down its length. I did a test fit, and they were the perfect diameter for the spacing between the upper and lower barrels.
The EL wire joins the output from the inverter in a pair of larger PVC tube sections, the larger of which was the same pipe I used for the "grenade launcher". As the small pvc rings are held to the acrylic tube by the friction of a thin layer of foam (Self adhesive door sealing strips) there only thing holding the tube in place are the two joining points at the front and back, meaning each has to be very secure. For the rear end of the tube I used multiple screwdriver extension bits to drive a 50mm screw through the back of the PVC pipe / wood cluster and into the main body, anchoring it in place. For the front end (The very tip of the barrel) I drove a 100mm screw from the lower barrel into the upper barrel, which not only secured it from moving forwards, but corrected the slight skep between the upper and lower halves that occurred as a result of minor warping in the wood.
Though the additional side panels were already glued in place, I had a small cut-out in the side of the PVC pipe that allowed me to connect the two ends of the EL wire. The 3v output was also present here, and although I have no use for it, I decided I would bring it to the outside just in case, and used another spare 3.5mm connector so that I could make minor electrical additions later on.
During the assembly I also added a 120mm picatinny rail for fun. One use would be an easy attachment point for a shoulder sling, because I forsaw this prop becoming very heavy, although a small flashlight or laser could be mounted and powered from the aforementioned 3v output just below it.
At this point, although there is a lot of sanding before painting can begin, I painted all the parts of the center barrel matte black because they would be inaccessible later on.
Step 7: Bodyfiller + Sanding
A cosmetic disadvantage of using wood for props is the woodgrain effect is always visible unless thick coats of filler or primer are used. This could be solved by using MDF, or another material altogether, but having already made the rifle I did what I could to hide the grain.
Due to time constraints I was unable to get the smoothness I wanted, but I was able to fill any holes caused by knots in certain sheets of ply, as well as smoothing over the joins between the ply sheets, or holes drilled to countersink screws.
Step 8: Armour Pieces
If making only the rifle, this and the following step are not necessary, but may serve as a useful reference for making armour pieces from scrap aluminium sheet.
I made some quick templates from reference images and riveted them together using tabs in a similar style to pepakura, using a combination of 40mm webbing and eva foam to attach them to the rest of the costume.
Step 9: Faceplate
There are several templates available online, both for use with foam and pepakura. For speed and comfort, I sought a foam template, and after some minor modifications I was able to assemble the majority of it using hot glue.
The main additions I made were the black tubing sections that join the ears to the chin (15mm hose shaped with a steel wire insert) and the visor. The visor was relatively simple to make: I used the section of paper cut out from the initial template to transfer onto an A4 sized sample of fluorescent orange acrylic (Available for around £3 to 4 on eBay), then created a 5-10mm buffer around it and keyed the buffer up using a hacksaw so that the hot glue would form a mechanical bond with the foam (Hot glue doesn't stick as well to acrylic as it does to EVA foam due to acrylic's low porosity). Before gluing it in place I used a heat gun to soften the acrylic around the middle third of the visor to produce a bend matching that of the faceplate. It's important to heat the visor evenly and test the amount of flex constantly so you don't overheat a certain spot and cause bubbles to form in the acrylic.
To simplify the painting process, it's advisable to postpone attaching the visor and EL wire strip until the paint and sealer has been applied.
Step 10: Painting
Since my airbrush was broken and I had to finish the paint job in 2 afternoon's worth of time, I used a few basic colours and gave everything a grime wash with a watered down black/brown paint before dry brushing silver accents on exposed edges.
The paint job ended up close enough to what I was hoping for, but the wood grain did show up more than I wanted, especially after applying a couple of coats of automotive lacquer.
Overall, the rifle turned out to be a success, and it serves as a reminder to me that there are often small, detailed parts with the right colour and texture that don't need to be made from scratch, and improve the build speed and overall appearance.