Sans Mask Cosplay (with LED)




Introduction: Sans Mask Cosplay (with LED)

#crafting #cosplay #sans #undertale

Hey guys. Today I will tell you, how I made mask for cosplay of one of the best characters from Undertale - Sans The Skeleton :) This is my first experience with polyurethane foam, LEDs, mask crafting and writing articles in English on Instructables :) So there are few errors with sizing of the mask (a bit big). But it looks fine :) So begin:

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Step 1: Sketch

First to start we need to make a rough sketch of Sans head, with the size of our own head. This will further helps us to orientate. Take three A4 sheets and fit them as at the picture. A small clarification - because I’m not so good in drawing, but I'm a bit "trust-me-i-am-engineer" - I chose a point that should be the center and after marked it with pencil... I hit the point with my nose. The second point - for the radius of our circle, was taken like about where forehead stops touching the paper. Draw a circle, then draw the eyes, smile, nose and cheekbones, approximately the as they are (it will be good practice for your drawing skills and how-to-draw-an-owl :))

Step 2: Base Framework

Let’s makе the framework for the mask. You can use a lot of things - balloons, covered with papier mache, cardboard, old ball , etc. But our spray foam is a really important thing for us, guys ^-^. Warning – it will be really difficult to rent a foam from everything: whether carpet, or clothing, or even skin. And if it happened that foam hit on the hand - drop anything you do and go to wash hands with soap, or even dish detergent, otherwise it would be really difficult, when it dries. If it is certainly happened and foam dried - Never try to use any kind of acid. Because your hands will start to be lobsterkind with the first degree burns for you (Say hi to my dota skills in picture 1 :) )

Here we need the cheapest spray foam . I paid something about 20 USD(analogue in my country). Take round box for cakes (unfortunately I haven’t this photo :( ) and just fill it completely with foam. After 6-8 hours, when the foam dries, we will have something looks like a ball. Especially it will remind you a ball if you have a good imagination. You can cut the rough corners of foam by the box cutter to make shapes of the ball, but I strongly advice you not to get too involved in this process. The size should be such like the face of the Sans, that we have drawn. Then glue it with papier mache (using PVA). Two or three layers of paper will be enough. It should be like in picture 2

Step 3: Base Framework 2

According to our sketch, draw eyes, nose and mouth with permanent marker. Like in picture (if you could see some inconspicuous black lines). This is in order to to use more foam in the mouth area in a future

Step 4: Base Framework 3

The frame is ready. Now you are going to have a really bad time :) . Here I used two foam container, but in fact could be used only one. It is advisable to do some stand for our carcass. I used inverted pot in which was inserted sushi chopsticks like in picture 1 (but I think you could use anything more useful)

This step is boring because foam likes to slip down, and more foam you place - more time it needs to dry. So we start from top and slowly lay it on with small spiral stripes. Try to make steps in a small areas to make it more easily to dry . When it dries in 6-8 hours, turn and make another area, and so on, until our ball becomes something like a burst of a bomb :) (Picture 2) When the papier mache is fully covered, fill holes with foam. This whole step should take approximately three or four day.

Draw eyes and mouth with permanent marker like in our sketch (I hope you have not lost, where they were marked in step 3? :) )

Step 5: Helm of Courage

Finally the most satisfying part starts after a few days of work: Cut circle on one side of this burst-of-a-bomb straight to papier mache (below mouth part), with size approximately to fit of your head (preferably cut a bit more for ventilation).

And start to remove our foam frame from inside with hands, spoons, scissors, knives and a bit madness, till only papier mache will remain inside. (Should be like in picture1)

Congratulations now you have the helm of courage!

Step 6: Eyes?

Do you remember all those times when we were draw sketches in our burst-of-a-bomb ? So now it’s the time to use them for its DETERMINATION. Cut eyes. (Not yours) ! Although ... Despite who do you want to cosplay in future))

Step 7: Mouth

We continue to show REAL KNIFE skills and we cut a smile (Joker you?), temples and nose (as in pictures)

Especially take a look at eye cutting (it was hard for me) - cut them once roughly in proportion, and do not touch them at all, or later you have add some foam or glue to them

Step 8: Fill the Holes!

Make shapes of the sketch by using the sand paper, and when it becomes look like in our sketch you can start to fill holes. And believe me - there would be a lot of them in foam. For this I used "liquid nails" type of the glue (It is on the background. White and orange)

It costs nearly the 5 USD. Also it is cheaper to use the "liquid nails" in tubes. By the way, this glue is very handy if you need to add size to our form.

Step 9: Stucco (fill Holes)

Now start to cover it with stucco. I took the cheapest one, it cost 1 or 1,5 USD. The main objective now is to fill all the holes that we have (But in real life you could stop with 90% of holes. Next step is a PAINting step). Please not use a lot of plaster , because is really heavy. Sans is enough big-boned :)

Step 10: Stucco 2 (fill Holes?)

After our plaster dries (about 2-3 hours), we should use sand paper (not again). Use all your determination to create the best round form

Step 11: Paining (and... Yes... Fill Holes)

Paint. All. In white.(Did you ever see non-white Sans?)

Draw lines with marker where it will be painted in black color later.

Step 12: Eyes, Nose, Tooth Ets

Suddenly! Paint lines with black.(nose , eyes, tooth ets)

Step 13: MOsquito Net

We need mosquito net for covering eyes and nose. Mosquito net fits perfectly – but it sold in stores only 1 square meter minimum (at least in store where I bought it ) and it costs something about 2 USD for sq.m. and we need a piece not bigger than 20x30 cm. Good for you if you have mosquito net remains somewhere in your house. Color of net does not matter, because you can repaint it (I strongly advice you paint by a permanent marker, do not use acrylic paint by this way). Cut the net, it should cover eyes and nose. Pin it with paper clips. Also then I stucked net by the thermal glue. It was glued to the bone

Step 14: Base Mask Complete

Paint mosquito net with marker. Paint two dots with white acryl as eyes. Paint all of holes on mask with white color. and black color. And make more details and correction if you need it

Main part is ready (WooHoo!)

Step 15: LEDs Introduction

Now I will tell you about LEDs and how it is going with them. I must say that I am quite a beginner, so I will explain it like for beginners)) Here we need:

- LEDs (3v white - 2 units; 3.5v blue - 8 units); //buy more, you generally can broke them

- Resistors (100 Ohm - 5 units)

- Switch (I use 3-position switch)

- Power Source (battery 9V);//Preferably buy two)

- Wire (1 meter, thickness 0.75 cm)

- Soldering iron and tin and rosin

- Insulation tape (Shrink wrap could be also useful)

-Painting tape will be also useful

Step 16: Some Schemes

First thing you need to know about LEDs and power source, if you have 9v battery, and 3v LED, do not connect them directly without proper resistor. LED will burn out. Also if you have 9v battery the best efficiency is when you connect up 3 x 3v LEDs series (9v=3v+3v+3v), but still it needs 1 Ohm resistor. But with parallel connection you can use any number of LEDs, but you must have resistors for all of branches. And if we would have a lot of LEDs in parallels, the source will be low of energy too soon (but in our case it is not important, 10 LEDs connected to 9V battery wont use much energy)

There are a lot of sites in web where you can count a scheme, with given LEDs and source parameters (direct current is 20 mA). Here you can see schemes for my connections. As I told I use 3-position switch. Where middle position is all of LEDs are off, left position is all white LEDs are on. And right position is all blue LEDs are on. Hard to paint it in paint, so there are few photos :)

Also - it desirable to place LEDs on a substrate so they do not shine your eyes, when they are turned on. I made substrate of conventional plastic card. After this action it is useful to paint substrate in black.

Step 17: Shiny Eye Trick :)

Here is one trick I want to share with - when you sold scheme, cover blue LEDs with thermal glue. The effect will be look like if they are fused. Also it is useful because it will help to hold LEDs on substrate

Step 18: Look to Inside

When you done with scheme and thermal glue (it is like to draw an owl, yeah? :) ). Put it in into mask. Try to tape battery at side, that it wont interfere with your face. For wires I used paint tape.

On the photo, where you can see white and blue wire, I attached it with thermal glue

Step 19: End

So now, ensure that Sans mask fits perfectly and wires do not interfere. If something is preventing - use tape or thermal glue (but not use thermal glue on power source :) ) and... PREPARE TO HAVE A BAD TIME >:)

1 Person Made This Project!


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5 Discussions


2 years ago

OOh, something to use to make myself into a meme amongst my nerds! haha. love this, though i'll probably not use LED's because I'm horrible with that kind of stuff. :)


Reply 2 years ago

Thank you )
I thought my hands were horrible too) But it took not a big time to understand) I'm sure u will handle with that!)


Reply 2 years ago

Eventually, yeah, I probably will. But until that day comes, I'll more than likely stray away from LEDs and have someone else handle them. When I do this, I'm gonna have Megalovania be on repeat and just blast it, see how many people will battle with me lol. x)