Wynta Handheld Fridge

Welcome to the full build guide for the world's first 3D printable handheld fridge, the Wynta! This design utilises a peltier TEC module, along with other off the shelf components to cool down your canned drinks in a comparable time to a regular fridge!

Unlike a regular fridge which cools down the air inside it, this cooler uses a more direct approach, literally! The can is kept in contact with the cold plate under pressure. This means a direct transfer of heat out of the can, and into the TEC module, making the Wynta one of the fastest and most energy efficient drink coolers that you can make yourself.

Please support my intructables page and help me make more cool gadgets by purchasing my design from cults3d:

https://cults3d.com/en/3d-model/gadget/wynta-handheld-fridge

-Standard PLA filament

-TPU 95A filament

-Peltier module

-90mm square CPU cooler

-1" Copper pipe

-4x M3x10 Countersunk screws

-4x M3 nuts

-Thermal paste

-Bench vise

-Steel ruler

-Phillips screwdriver

-Pipe cutter (optional)

-Hacksaw

-Hammer

-Plastic or Nylon hammer

-Sandpaper

-Butane gas torch

-Cold chisel

-Peltier Module:

https://www.aliexpress.com/item/1920892048.html?pdp_npi=2%40dis%21AUD%21AU%20%241.21%21AU%20%241.21%21%21%21%21%21%402103239e16770280571495983e6de1%2110000000200160713%21btf&_t=pvid:9f7f6b6a-dd71-4aa3-9e47-aaede5ef2bcd&afTraceInfo=1920892048__pc__pcBridgePPC__xxxxxx__1677028057&spm=a2g0o.ppclist.product.mainProduct

-CPU Cooler:

https://www.aliexpress.com/item/1005004849055115.html?spm=a2g0o.ppclist.product.2.69a9xCzyxCzyBT&pdp_npi=2%40dis%21AUD%21AU%20%2419.70%21AU%20%2415.95%21%21%21%21%21%402101f6b316770276995147880ef6b9%2112000030740962355%21btf&_t=pvid:92e80daf-eef8-4dcc-86c6-283719db6d60&afTraceInfo=1005004849055115__pc__pcBridgePPC__xxxxxx__1677027699

-Copper for Cold Plate:

https://www.ebay.com.au/itm/304498884797?hash=item46e58c40bd:g:a7cAAOSw~W5iiwmj&amdata=enc%3AAQAHAAAA4CIKs2%2FWau8ymZBQkL2QJwf6yyn9Bgfxw7uq2CFzizaTB2aifoIEZy7SnyspbIfCeoTk11EkHc7DgXWdoeMk4nqPfrRlwA0u5bHJ0IN8o4walDyszcoEunwUPW04d4A%2FgJsmV768DZExErC5DI1rVM6BHVLYqbML8SfahDPpPo6VVcR%2B5wlDxFcvfIVXrjXc5Nvov1YuQUFWPyq5fpjeFpgVUx5iyszASH7uSrQWNgVDxRjpPH3DXJquuFDBpwIZql0%2FLUPahbUHvQ87l11l8pp16zP6VujKS1dIvGNI99mJ%7Ctkp%3ABk9SR4jwuOrOYQ

Printing is quite straight forward, i've designed this model to work well with mostly standard settings in the CURA Arachne Engine, and standard PLA filament, so as long as your printer is calibrated, printing should be a snap!

-The Base can be printed without supports, 2 walls, and 10% infill. I've found this to be about the minimum before structural integrity becomes an issue, also some light will leak through the print walls, exposing the infill pattern if placed in sunlight, so i recommend if you want a more aesthetically pleasing print, use at least 3 walls.

-The cooling chamber can be printed in much the same way as the base, with the same considerations for light leakage etc.

-The cold plate bracket is under quite a lot of flexural stress from the CPU cooler, therefore it is necessary to print it to be much more robust, typically I would use 4 layers on the top and bottom, and have a minimum of 4 walls, about 25% infill for this part.

The cold plate is simple to make, but takes time and perseverance for a good result.

Start by cutting a roughly 80mm length from your 1" copper pipe, a pipe cutter makes this much easier but is not essential.

Now you'll need to heat the copper pipe up nice and hot, get a butane gas torch and heat the pipe until it is faintly glowing, without melting, the hotter the better, then quickly submerge the metal into some water, this will soften the copper and prevent it from cracking when you go to manipulate it in the next step.

You'll want to mark a line running down the length pipe you cut, put it in a vise, then go ahead and cut along that line only through one side of the pipe, you should end up with a "C" shape. Now insert something round into the cut pipe, a large bolt, a broomhandle, even a smooth rock would work, and start prying the metal open.

Once you've opened the metal enough, you'll be able to start flattening it out with your hammer and a flat surface, most bench vises have a flat surface on them suitable for striking with a rubber or plastic hammer. Begin flattening out the metal.

Now that you have a roughly flat plate of copper, you'll want to mark out the diameter using a compass, the final diameter of the plate should be at least 59mm but no more than 62mm to ensure a good fit. Use a cold chisel and a large metal hammer to cut out the shape of the copper disc, a file can be used after cutting to clean up rough edges.

Almost done! now we have to sand the plate to make it as flat as possible, use either some flat concrete, or a known flat table surface with some sandpaper laid on top. Check regularly with your steel ruler that you don't have any high spots, this can be done by holding the edge of the ruler perpendicular to the surface of the cold plate, holding it up to a light source, and looking for gaps between the ruler and the cold plate. If there are any significant high spots, indicated by light leaking between the edge of the ruler and the coldplate, you can hammer those out gently before continuing.

Most importantly, take your time, and get at least one side very flat and smooth, the other side will be against your drink, so perfect flatness is not essential.

Assembly is simple, start by taking a square of styrofoam roughly 100mm x 100mm x 8mm, and pressing it onto the cooler, this will mark where the 4 bolt holes are in the foam and make orientating other parts easier.

Then take the cooling plate bracket, and firmly press it onto the foam square, being careful to align the holes of the bracket, with the marks you made in the foam earlier.

This will leave you with a nice outline of where you need to cut the foam.

You will probably need to trim and adjust the foam, you can see the shape i ended up with from the photos.

Then it's simply a case of attaching the CPU cooler to the hot side of the peltier, and the copper plate to the cold side, make sure you apply just enough thermal paste to both sides of the peltier, then sandwich all of this together using the cold plate bracket and 4x M3 nuts. Ensure that the cold plate itself is centered in the bracket before tightening down.

Now that you have the core of your Wynta complete, it's time to assemble the rest of the project.

Start by lowering the core into the Base, there may be some friction as the part is designed to fit snugly. Ensure that the direction of flow is correct; you want the air to be sucked through the slats in the base, and blown out the circular hole on the backside. Also ensure that there are no pinching wires.

Insert the M3 countersunk screws into the side of the base, aligning them with the cold plate bracket, and screw them in. Be sure not to overtighten.

Now just insert a can of drink of your choice into the cold plate bracket, it should be a snug fit that can hold the weight of your can, but still be easily maipulated in and out.

Lower the whole assemly into the cooling chamber, and you're done!

Now just supply 12V DC to the cooler's fan, and the peltier module and enjoy your cold drink after around 2 hours of cooling time, comparable to a standard fridge! Not bad for something you made yourself, eh?

The Boring Stuff:

My instructable includes the use of dangerous tools, gas torches, saws, potentially a soldering iron, and it must be said that you are responsible for your own actions. I do not, and will not provide advice on how to connect the electrical components, nor what kind of power source you should use, i only state that the electronics i recommend using require 12 volts DC, how you power it is on you. So if you burn yourself, or cut yourself, or start a fire because of bad soldering i am NOT responsible for that.

If you want to make this project, but you are not confident in your own abilities, then i recommend going somewhere like a robotics club, or some sort of hobbyist group, or even if you want to spend the money, hire an electrician to do the work for you and verify it's safe.