Introduction: TARDIS Fading Light Bag - It's Bigger on the Inside...

It's bigger on the inside…

I like bags.

And since my last messenger bag I also like electronics in bags.

And I never worked with microcontrollers before.

And I wanted an eye-catching inconspicuous bag.

Perfect combination.

I want a fading TARDIS bag which is bigger on the inside - especially because grocery shopping is usually more than expected…

Attention, this appeared to become a longer instructable than I expected. You don't have to do (or read) everything.

You could also do parts of this instructable or different combinations, also depending on your time you like or have to spend.

For example add a fading TARDIS on a bag which you already have (from step 6)

Or just sew the bag (it is very handy and light weight). (from step 1)

Or just sew the bag and add the TARDIS, but forget about the programming and the light. (ignore step8+9).

Step 1: Material and Tools

For the bag:

For the TARDIS

  • 1 piece of blue form felt, its a stiff felt
  • 1 piece of white flex foil, ca. 6x8cm
  • 1 small piece of white fabric
  • 1 small piece of black fabric
  • Black yarn, white yarn + Yarn in your fitting color
  • A printed TARDIS image (ask google) or your computer to have it on the display and some white paper
  • A plotter (I use a silhouette cameo)

For the electronics

  • Conductive Thread
  • 1 microcontroller - I used the Adafruit Gemma
  • USB 2.0 Hub for programming your Adafruit Gemma
  • 1 LiPo battery
  • 1 charger board (5V Micro USB 1A 18650 Lithium Battery Charger Board Module TP4056 TE420)
  • 1 2-pin cable
  • 1 white sequin, (I used a lilypad white)
  • 1 switch (I used a lilypad slide)
  • Micro USB cable (and USB 2.0 hub) for programming the controller

General tools:

  • Pencil
  • Sharpie, Edding or Ball pen
  • Ruler Scissors
  • Optional: rollcutter + cutting board
  • Sewing maschine
  • Wonderclips (or pins, I mostly prefer wonderclips because the don't cast holes in the fabric)
  • Sewing hand needle
  • Safty pin
  • Hot iron
  • Seam ripper (it's always good to have a seam ripper while sewing, but you can also use sharp scissors or an x-acto knive)

Step 2: The Pattern and the Bag

I made two test bags out of cotton, which didn't totally convince me, so at the end I made it as easy as possible. Sometimes the easiest way might end up in the expected result.

Of course you can create your bag with every fabric you like, but I recommend a rip stop nylon.It's very light weight and if it gets a punch hole or a cut, it doesn't continue breaking due to its weaving structure.

Since I don't know how familiar you are with sewing let me quickly explain some sewing terms:

(if you are firm with sewing or if you don't want a bigger on the inside bag you can skip to Step 6 )

  • Right side of the fabric - the side which will be seen on the finished piece, the "nice" side (in the drawings blue)
  • Left side of the fabric - the ugly or unwanted side (in the drawings grey)
  • Right on right - the nice sides of the fabric are on top of each other
  • Left on left - you guessed it already, it's the other way around
  • Turn around - turn the inside out (or the outside in)
  • Seam allowance - the distance you need to keep to the border of the fabric
  • French seams - technique to hide the open material edges
  • Sew up - sewing some stitches for and back to avoid opening the seam by itself

The pattern:

  • 2x 50x70cm the body
  • 4x 11x70cm the handles
  • 1x 5x70cm the loops (actually you only need 4x 15cm, but if you are using a roll cutter you can just measure and cut and then trim to specific length)
  • Optional: your own clothing label

Sewing instruction:

  1. First fold the upper edge of your first body piece two times, with the right side visible - first at 1cm and then again at 4cm, stitch down with one or two seams
  2. Repeat with second body piece.
  3. Staple both body faces left on left. Sew around the sides with seam allowance of approx. 4-5mm , now you already have something like a bag, at least you can put something into it)
  4. Now turn the body inside out and repeat sewing the borders with 1cm of seam allowance. With this step we make sure that the seams are stronger and the inside of the bag looks cleaner, it's also called french seams.

The next step is done to create a bigger bottom. Until now the bag would be like an envelope or an ordinary plastic bag, but with forming the corners its appearance becomes more of a bag one.

  1. Turn the outside in and take one of the corners from the bottom. Flatten it to a triangle and make sure that the seams are on top of each other.
  2. Take a ruler and measure ca. 10cm (4inch) from the corner, make a line and sew with a straight stitch, don't forget to stitch up. Repeat with the other corner.
  3. Cut the corners off. Leave around 5mm of seam allowance.
  4. Turn the inside out and sew the corners with 1cm of seam allowance.
  5. Turn the body again - your main bag is finished.

Step 3: The Handles and the Small Patches

For the handles

  1. Take one of the 11x70cm pieces and fold them in the length right side to right side.
  2. Sew along the long side.
  3. Now you need to turn it inside out; this is easily done with and sewing saftey pin. Just stick it into one endside of your handle tube and lead it through the tunnel.
  4. Flatten the handle and sew on both length sides with approx. 7mm (1/4'')
  5. If the seam is in the middle this side will be handled for the future as a "left side". If you put the seam to one border and both sides look the same it doesn't matter.
  6. Repeat another 3 times

For the small patches

Those are needed to strengthen the gaps where the handles will go through.

  1. Cut your 5x70cm strip into 15cm pieces.
  2. Fold one piece in the middle to 5x7,5cm
  3. Sew around the edges, but leave a turning hole so you can turn the inside out.
  4. Repeat 3 times.

Step 4: The Body (and the Label)

Yes, I have to admit it, I forgot in the planning to add the label before sewing the body, but since I'm sewing the bag I can add it in the process. :-)

  1. Measure 35cm from the bottom seam (there where the seams look like a cross) and mark it. This will be the heights of your bottom bag.
  2. (If you want to add an in-seam label (like I did) you need to take your sharp scissors or your seam ripper and open the seam from the outside for the length of your label. Hold the label and fix the seam from the inside.)
  3. Clamp both sides of the seam with your wonderclips (or pins) heights and straighten the corner between the side seams. Clamp it.
  4. Sew with a distance of 2,5cm (1inch) around the top.
  5. Now you can pull out the upper part of the body again and you have a "bag with a belt".
  6. Take two of the small patches and place them on the "belt" where you want to have your handles. (I set them approx. at 1/4 and 3/4 of the flat width of my bag.)
  7. Sew a square on the patch. This will be the gap where the handle runs through, so it needs to be a little bit longer than the width of the handle.
  8. Cut carefully a "double inverse point arrow >------< " into the square.
  9. Squeeze everything through the hole and sew along the borders of the window.
  10. Voilà, the first handle window is done - repeat another 3 times.

Step 5: Adding the Handles and Finishing the Main Bag

In this step the handles will be sewn to the body.

  1. Thread one handle through the windows like seen on the scheme picture 1, this will be the lower handle.
  2. Take another handle and lay it on top of the lower handle, this will be the upper handle.
  3. Stitch both handle ends together.
  4. Then fold one end around the upper edge of the body bag and cross stich it together - as in scheme 2
  5. Repeat for the other end.
  6. Then repeat for the other side.
  7. Hooray, your shrinkable main body bag is finished

Step 6: The TARDIS

  1. Search for an TARDIS image online, or take the one you saved already to your disk.
  2. Either print the image in your preferred size, my TARDIS is 10x16cm or size it on your monitor and take a white paper to copy it from your screen. (Since my printer doesn't work right now I needed to go for the second option.
  3. Cut the outer edge and place it on your felt. Depending on your size you might need to size up the signal light on the top.
  4. Mark the outer edges (with the up sized signal light) and cut it. Then cut the TARDIS out of your felt piece.
  5. Copy the details to the felt piece by punching your sharpie into the edges of the details.
  6. Either connect the lines with your pen or make the connection mentally.
  7. Change your thread in the sewing machine to black color and now carefully trace your markings. In this case DON'T stitch up at the end of the seam. You will later stitch it up by hand. Try not to sew over your remaining threads on the felt, otherwise it will be difficult to hide them.
  8. Sew all thread ends by hand on the back side of your TARDIS. Knot them together, always 2 threads at a time and cut the remaining threads.

Step 7: The White TARDIS Details

Take your TARDIS image and load it into your silhouette software. (Or just download the file and save some working time :-) )

  1. "Open the trace window" and click on "Select trace area".
  2. Select the writing. I'm using the following settings, but just fit them like you want to.
  3. High pass filter 74,0
  4. Threshold 39,7
  5. Scale 4
  6. Press "Trace the entire image" button.
  7. Your yellow image now swapped to red thin lines. Drag the image and drop it to the side.
  8. Mark your red lines and click "Release Compound Path"
  9. Delete all the lines you don't need, you only want the lettering.
  10. Depending on your TARDIS size you might narrow the space between the words (at least I needed to do this) otherwise the writing would be too small for cutting. So measure the space you have for your writings on your felt piece. Then mark the whole writing and size it to your measured height. Mine was at 6,82cm but the length was at 75mm, and I had to cut it down to 65mm. Mark "POLICE" and slide it to the right to "public call" then mark "BOX" and slide it to the left, until you have your desired length.
  11. Mark everything and "Make it compound path" again.
  12. Flip horizontally (since you don't want to have it in mirror writing on your bag).
  13. Create the windows and the plate: You can either also trace it with the tracing tool or you do it by hand.
  14. Take your preferred flex foil and cut it.
  15. Weed the cut outs - you're done with the writing.
  16. Place the plotted parts on your felt body, heat the iron to the needed temperature (depending on your foil) and press it on…
  17. Check on your images where the small door knob is (yes I know it is actually the door lock, but now it will be both, knob and lock aka. switch) and cut a small hole in which is big enough for the movable part of your switch

Step 8: Programming Your Adafruit GEMMA

First of all, this was my first time programming anything. So please notice that everything might have been done in an easier and more elegant way, but that's how first programs might look like (at least in my case).

I wanted to simulate the blinking/fading of the head top lamp of the TARDIS, so an ordinary blinking or equal fading mode was not what I was up to.

  1. Make sure that your Computer has an USB 2.0 port and/or you have an old USB hub available. I found out that my USB 2.0 ports at my old laptop don't work with the Gemma, neither as my USB 3.0 ports. So grab your old hub - it might probably work, if not, you might have an charge only cable (see point 2) (or your Gemma is broken). The red LED on your microcontroller should be blinking when you connect the controller with your computer the first time.
  2. Make sure you're using an micro USB data cable for the programming. There are cables in the world which are "charge only" - I didn't know that… It took me 1,5h of internet research to find out that I own one of these cables :-(
  3. Clarify if you have a black or a purple Adafruit Gemma. Yes, there is a difference. No, I have no clue what the difference is. I only ordered an Adafruit Gemma and I got a black one.
  4. Download the Arduino software, (mine is version 1.8.2).
  5. Set in the "Tools" folder the "Board : Arduino Gemma" and for "Programmer : USBtinyISP" The choice of the port doesn't matter as long as you have a data cable and an USB 2.0 hub for the data transfer, it will be picked automatically.
  6. Open the program TARDIS_fading.
  7. Check it once by clicking on the "Verify" button.
  8. Press the small black dot on your Adafruit Gemma and while the red build-in LED its fading upload your program with clicking on the "Upload" button.
  9. Your LED should start fading in an irregular-regular way.
  10. Congrats, now your light is ready to fade with you through the universe.

Step 9: Combining Electronics and the TARDIS

I'm not so used to electronics and there will be probably better ways to set this circuit up, but for me it worked quit fine. If you have any advice for me to do better, I would like to hear it either through the comments or via a private message.

Since I don't really know how to describe the set-up of the circuit please find a scheme in the pictures.

  1. Sew the gemma with normal thread to a small piece of felt using the unused connection holes. It's easier to stitch felt to felt than the microcontroller directly.
  2. Sew the felt carrier to the TARDIS.
  3. Sew the sequin with conductive thread to its specific position at the top lamp. Be careful to not connect the conductive threads between each other.
  4. Use the advantage of the form felt and stitch the conductive thread in two lines to the specific connections. Double sew around the connections and solder it.
  5. Solder the LiPo battery to the +B and -B connection of the charger.
  6. Solder the 2 pin cable to the out- and out+ connection of the charger.
  7. Cut the black (out-) cable in the middle to solder in the switch.
  8. Take the small piece of white fabric and sew it with white thread on the top lamp of the TARDIS.
  9. Then trim it to form.
  10. Depending on your fabric you can now take a sharpie and blacken the top of the lamp. I couldn't do so, because my fabric out of siliconised nylon and the sharpie didn't paint on it. So I needed to repeat the previous step with a small piece of black fabric.
  11. Sew the switch with normal black thread into position and also fix the charger and the LiPo battery on its place.
  12. Cut all unused ends of normal and conductive thread.
  13. Sew the TARDIS by hand to the main bag.

Step 10: Go Out and Let It Fade

Enjoy your finished "it's bigger from the inside bag" and let it fly through your universe.

By the way, mine will be at SPIEL 2017 in Essen and if you would be also there and see me in the crowd I would like to give away the code for a 1 year PRO membership for Instructables. So, just speak to me :-)

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Runner Up in the
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GIFs Challenge 2017

Participated in the
GIFs Challenge 2017

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