I designed this money box a while ago and never really got round to doing anything with it....until now! Seeing the FormLabs contest gave me the motivation I needed to sort this money box out and get it on to instructables. So, why do I deserve a 3D printer? Well, to quote Howard Stark; "I am limited by the technology of my time." Well, the stuff I have access to anyway... A 3D printer would allow me to take my designs to the next level, I could produce products which use a blend of different processes and techniques to really create something innovative. So if you like my instructable please vote :)

So lets begin; I've attached all CAD files for you guys to download so you can simply cut out your own parts, alternatively, if you cannot get access to a laser cutter, message me and I would be happy to cut and send you them to you for a small fee (covering materials and postage).

If you have a laser cutter, simply cut the file out of 3mm material, I used MDF. Then print off the sign board decals.

When you have all of the parts in front of you, the assembly is pretty easy.

Step 1: Gluing the Top

First, find the two light parts and using a small amount of PVA glue, slot them together.

Next, find the two small squares with the cross cut outs and again using a small amount of glue stick them together and then fit the light assembly into the cross shaped slot. Ensure the light goes all the way through both layers.

Now, find the two larger squares and glue them together concentrically as shown. After a few minutes the light will hold in place and you can glue the whole assembly together.

Step 2: Inner Casing

Whilst the top drys a little, it's time to fix the inner casing together. Lay out the pieces as shown so you can identify the order in which they go together. Start by gluing the base piece into one of the sides. Work your way around the base piece gluing each side on in turn. Secure with elastic bands and allow to dry for a few minutes.

Step 3: Outer Casing

Remove the elastic bands, then identify the smaller outer panels and stick them on first. Align them with the edges of the inner casing as shown. They should be on the opposite sides to each other. Once in place, the two larger panels should then align with the edges of the two outer panels already in place. Use elastic bands to hold them in place. Pay attention to the panel with the money slot, ensure you align this with the side on the inner casing with the corresponding slot.

Step 4: Adding the Roof

You should be able to easily align the whole top assembly with the main body and stick in place.

Step 5: Skirting

One of the final details is the skirting on the bottom. Like the outer panels you need to pay attention to the larger and smaller pieces and fit them in pairs opposite to each other as shown. Again, if you don't find it too fiddly, use an elastic band to hold it all in place.

Step 6: Sign Boards

Align all four sign boards to the top edge of the outer panels as shown, taking care to not cover the money slot, stick into place. Hold in place with an elastic band.

Step 7: Plug

The plug assembly will allow you to easily access your money when required. To make it easier to turn, start off by adding a small taper to each tab as shown. Then glue the three parts in place ensuring you align the tabs with the small mark. This mark will allow you to easily lock and unlock your plug when fitting to the base of the TARDIS. There are two marks in the base, one indicates the lock position and the other the unlock position. Allow this piece to fully dry before fitting. When dry it should fit into the hole underneath and turn 90 degrees to lock in place.

Step 8: Finally!!!

Right then, a little light sanding on the edges and some paint will really bring your TARDIS to life!! A few of my sixth formers suggested I add a monostable circuit which turns on an LED mounted in the light assembly triggered by a micro switch which is positioned inside the box next to the slot. When you place money into the TARDIS the money catches the switch triggering the circuit. This is a great idea and there are plenty of instructables out there to help you add this great feature.

I hope you enjoy making this a much as I did :)