Cooler With Blender, Speaker & More




Introduction: Cooler With Blender, Speaker & More

I started this project earlier this summer with one goal: have more fun outdoors by bringing my music and tasty blended drinks to the adventure.

I know first-hand how much fun it is to have a cooler with speakers, and a portable blender for margaritas and smoothies, because I built myself one of each almost ten years ago. I tried to bring them both to a party this year and got frustrated when I couldn't get the gas powered blender to start up and the old lead batteries for the stereo were dead.

Technology has come quite a ways since I built these toys, so I decided it was time for a remix. This one would be portable, reliable, and also tackle three other things that annoyed me about coolers.

I call it the COOLEST :)

I'll show you step-by-step how you can build a 'Coolest' of your own, or just improve your exiting cooler and add some or all of these features:

I launched a Kickstarter to bring this idea to life, which ends Christmas at midnight. You can check it out here:

My original plan was to make this idea my first Instructable project, and I hope you like it. I've also decided to enter it in the Outdoor Projects Contest, so please vote for me if you think any of these cooler mods would improve your next outdoor adventure!

Step 1: Stuff You'll Need

Warning: things that are sharp can cut you, things that are hot can burn, etc, etc. If you're not sure how to safely use any of these tools you can probably find an excellent instructions right here on this site. Ok... on to the fun!

Main components

Fabricated or 3D printed parts (files included)
  • Blender holder
  • Battery holder
  • Speaker holder
  • Button hinge
Not everyone has a 3D printer (yet!) but you can get these parts printed at Shapeways, or use your DIY craftiness to figure out another solution. Perhaps wood, or using Shapelock?

Miscellaneous components:

  • Wire (I used speaker wire)
  • Copper strips for battery housing
  • SPDT Switch
  • Pop rivets (3/16" and/or 5/32")
  • Wire connector
  • Large zip ties
  • 3/16" bungee shock cord
  • Plastic epoxy

  • Utility knife with new blade
  • Dremel
  • Pop riveter
  • Drill
  • Screwdriver
  • Ruler
  • Saw
  • Tin snips
  • Soldering iron
  • Sharpie
  • Caliper
  • Hot glue gun
  • Angle grinder
  • Sander (belt)

Step 2: Add a Blender to Your Cooler

I love the great outdoors and when it's hot out there is nothing on earth more refreshing than a blended drink. I love that I can make smoothies or awesome blended drinks anywhere.

WARNING: Don't add a blender to your cooler if you do not want attention

Few things I've ever built have received the kind of reaction I got when I took my 'Coolest' tailgating and fired up the blender. If you're prepared to share your tasty cocktails, here's how to add a blender to your cooler.

1. Cut out a cup holder

Print out the PDF guide and trace around one of your cup holders closest to the hinge, preferably the left hand one when facing the front of the cooler. You'll only want to cut the top of the lid at this time as this is where your blender holder part will go. If you don't have the 3D printed part, you can use the Shapelock material and make one that will securely hold the blender in place.

Place the blender holder in the opening and mark the location for your center hole. Drill a 1/2" hole in that location.

Save your PDF guide as we still need to make the holes that will line up with the blender holder, but first we want to get our motor in place.

Step 3: Prepare the Motor

I first tried using the motor from a cordless circular saw, but once I had it installed I found that the speed and torque just wasn't there for crushing the ice for blended drinks. In take two I upgraded powerhouses to this Porter-Cable 18v angle grinder, with 8,500 rpm of power. The attachment isn't beautiful, but it's secure and effective.

1. Break down the angle grinder by removing the grinder guard, handle and the black section that threads onto the threaded shaft.

2. Angle Grinder vs. Angle Grinder
The output shaft from the angle grinder is a threaded rod. We need to make that into a XXX square shaft that will lock into the base of the blender pitcher and spin that blade. I used an angle grinder with a metal cutoff wheel to perform the surgery. This was actually easier than I expected. Mark your centerpoint then start cutting the edges off of the threaded rod in equal and parallel cuts. I found it was easier to first cut a larger square shaft, then carefully grind a little more off each side. I used my calipers to make sure that the width of one side was the same as the other. Mine are .238"in width.

3. Shape the shaft
Using a Dremel and a cutting wheel attachment you now need to shape the shaft so the blender base can easily connect to and be removed from the blender holder. This is accomplished by rounding the corners on the side of the shaft, and then rounding the top as well. Now when the blender base is placed on the shaft it will easily self-guide into the opening.

4. Trim the plastic to extend the shaft
To make sure that our shaft can reach all the way through the cooler lid, we need to trim away some of the plastic around the shaft base. Luckily the fine folks at Porter-Cable put a line here that we can saw or Dremel around.

5. Housing flip-flop
IMPORTANT: We need to disassemble the housing because we need to rotate the output shaft 180 degrees. This is done fairly easily by taking each side of the handle off and putting it on the opposite side. This is necessary because in the next step as we need to have access to the housing screws when we mount the motor to the lid. While you're in there remove the trigger and save for a future project.

6. Chop off the excess
Using a saw or band saw cut off the excess plastic housing that extends beyond the motor housing. Now we have a nice little motor with drive shaft that we can mount into the lid.

Let's jump forward a step and bring power into the lid.

Step 4: Mount the Battery

The battery I used was my Makita battery which worked out well because it locks in place with a sliding connection. I measured the base of my drill and, using my CAD software, printed up a battery holder for my 'Coolest'.

1. Print out the 3D file
You'll need to add metal strips for the battery to connect to. I used copper because I had some around, but any conductive metal will work. Cut out a strip and make it long enough to stick out slightly from the back.

2. Solder the wire to the metal strips
Roughen the copper with some sand paper and add a little flux. You'll solder the wire to point straight out from the back of the battery holder.

3. Install the wiring
Decide where you want to mount the battery holder on the back of the cooler. Use a sharpie and draw a rectangle where the wires will go into the cooler and also come out to connect to the lid. Using your fresh blade you'll find it very easy to cut through the cooler housing, but a dremel works too. I found it most effective to use a rocking motion for very controlled cuts. The urethane foam is easily removed with a screwdriver. With the foam removed you may be able to simply push the wiring up, otherwise you can tape the wire to a dowel or screwdriver and pull it up through the openings.

Hold off on pushing the wires into the lid until we prepare the next step to mount the motor.

4. Mount the battery holder
Decide what size pop rivets you'll be using (I used 3/16") and drill 5 holes in the battery holder the same size. Place the battery holder in it's final position, mark the holes, drill, then pop rivet in place. You 're battery holder is now all set!

Step 5: Install the On/off Switch

I don't have a great picture of the first step, but basically we need to cut out a section of the lid so the grinder motor can sit flush and the shaft can extend through our blender mount hole. Since every cooler will be slightly different I'd suggest just tracing your grinder housing on the cooler lid (to get a ballpark) then cut away less than you think you need. Your strongest and best mount will incorporate as much of the lid structure as possible. Once you have a section cut away and your grinder lines up pretty well move to the next step.

1. Wire to the lid
Now that we have a nice opening, lets bring up our wiring. Cut a vertical slit approximately 1/2" tall and 1/4" wide on the back of the lid directly above the battery mount for your wiring to enter the lid. If you make it too small (like I initially did) the wiring will be strained and crimped with each lid opening and will eventually break so give yourself a little room.

2. Prepare the Hinge
3D print the hinge. The hinge lets a pieces of your cooler be the button to push to turn on your blender but you can simplify this step and just use a momentary button if that's easier for your cooler. If you're going for it, take your switch and decide where your button will be. Cut a rectangle out of the side of your lid the width of the switch and the height of your lid (taller is better). Install the hinge to the top of your cooler lid and see how much of the rectangular flap you'll need to trim away so everything lines up. Once you get it working just right remove the hinge flap so we can continue.

3. Wire to the switch
Take one of the wires and another single strand of wiring and bring them to the switch location. Install female wiring connectors to the wires, and giving yourself some slack, connect to the momentary switch.

4. Install the button switch
I needed to bring the height of my momentary switch up slightly so that the hinge flap would hit it properly. I used a piece of plastic to shim it slightly, then drilled holes for a 5/32" pop rivet which fit perfectly through the momentary switch. You need to carefully line up the momentary switch location with the position of the hinge flap. When you have your position perfected, drill and pop rivet in place. Place the hinge flap back in place and push it a bunch of times. Ahhhhhh...... well done!

Step 6: Install the Motor

We're getting pretty close, but this next step is a little tricky. You should be able to hold your grinder motor in its final position, with the shaft sticking all the way through the opening hole, and we just need to make it stay there. Using your sharpie, or better yet a sharp knife, mark as many places as possible to help with positioning.

1. Test motor rotation.
Before we go any farther lets make sure our motor is spinning in the correct direction and all our connections are good. Place female connector on the remaining wire from the battery, and also on the other wire coming from the switch. Connect your battery. Connect wires to your motor and make a mark when you figure out which way makes your output shaft rotate clockwise, which is the direction your blender blade needs to rotate to best destroy the ice.

2. Disassemble the motor housing
When you hold your motor in its final position, you need to make sure you can get access to the side screws from below. If not, go back to step #2 and flip the housing position. When everything is correct, remove the back section and prepare to pop rivet it in place.

3. Pop rivet motor housing side
If your housing is not sitting flush to the lid you may need to use a shim as I did. I'd suggest hot gluing the shim in position. Using the marks you made, line up the motor housing as best you can and drill multiple holes sized for your largest pop rivets. Before you pop rivet you really want to vacuum out the inside of the lid (trust me!). Install the pop rivets, connect the wiring and reassemble the motor housing. Hopefully your shaft is extending proudly through the hole and we're almost ready for cocktails!

4. Secure your housing (later)
I initially used some large zip ties to further secure the housing in position, but later decided it was unnecessary. What I did instead was use copious amounts of plastic epoxy to keep the housing from wiggling around. Save this step for AFTER you get the blender housing mounted because you want to make sure everything is lined up just right

Step 7: Install the Blender Holder

We didn't install this part from step one because we wanted to make sure the output shaft was going to line up properly. Hopefully you're well centered, but if not now is the time to shift your opening slightly to accommodate the shaft position. When you have your position determined we can proceed.

1. Drill some holes
Using your PDF template drill 8 holes in the lid which will line up with the holes in the blender holder. Place the blender holder in position and you may want to drill another few holes in the bottom as shown. All of these holes will be filled with epoxy and will help hold the blender holder in position. It's a good idea to test fit your blender again just to make sure everything fits well.

2. Epoxy
Mix up your plastic epoxy and apply generously to all sides making sure to also apply to the underside of the lid holes. While many plastic epoxies claim to join all sorts of disparate plastics, epoxy sticks best to itself. I think of these as epoxy rivets, so rather than just connecting surface to surface, we'll have shafts of epoxy that are connected to an underside ring of epoxy. Clamp or use heavy weights while the epoxy sets.

3. Test
You've just installed a blender in your cooler. Now is the time to test your favorite blended drink or smoothie. Not too many though... We still need to get our music in there!

4. If your angle grinder is still moving slightly in there, now is the time to line it up just right then use some plastic epoxy to keep it in place.

Step 8: Add the Bluetooth Speaker

The lowest hanging fruit, and something that you can easily add to almost any cooler, is a simple shelf to hold a Bluetooth speaker. Speaker technology has really come a long way, and its surprising how much sound you can get out of one of these little boxes. The party is always at the cooler and it's great to DJ the music as I wander around.

That said, pick up any size powered Bluetooth speaker you want just make sure it's less than 2" in thickness. Most coolers have close to that much spacing for insulation in the front and it's quite simple do. If you happen to have the same speaker and cooler as I used, you can simply print out the shelf file of your choice, cut a hole and you're set. I first made a version to hold the speaker, then later went back and expanded it to hold my phone and keys while I'm on the beach.

Here's how to customize for your set-up based on what I've learned:

First we need to figure out how big our shelf/box will be. Start by measuring the size of your Bluetooth speaker. You want to build a simple box around it that you'll insert into the front of the cooler. Make your box 1/2" taller than the height of your speaker, and 1/4" wider. This way you can easily remove it from your cooler for charging. So if your speaker is 6" x 2" x 2" your simple box will have in inside diameter of 6.25" x 2.5". If you're using 1/8" wood, your outer dimensions will be 6.75" x 2.75".

Your box doesn't have to be all that sturdy as we'll be gluing it into the cooler and that will stiffen everything up.

You'll either want to put a faceplate attached to the front of your cooler or a small lip at the bottom of the box like the image I included (small lip is easiest). This will keep your speaker in place as you're rolling the cooler around yet still allow you to remove the Bluetooth speaker when you wish. I made the lip in this image 1/4" tall. If your lip is also made of the 1/8" wood, the depth of your box should be: speaker thickness (2") + lip thickness (1/8") + extra room (1/4") = 2 3/8".

Now measure the outside dimensions of your shelf/box and trace that out on the front of your Cooler. I'd suggest a mid to lower-mid position as that's where coolers are generally thicker. The inner wall of the cooler typically slopes in slightly so you may need to cut or grind an angle into the back of your box as shown in the secnd to last picture (hence the extra 1/4" in depth!).

Use your utility knife to trim the edge of the foam all the way back to the inner cooler wall, then a flat-head screwdriver to pop out the foam.

A line of hot glue around the back edge of the box should be all you need to hold your box in place, or if there's a little extra gaps on the side you can use silicone as well.

Insert Bluetooth speaker and proceed to rock out!

Step 9: Let There Be LIGHT

If you spend any time outdoors camping with coolers, this is one of the easiest and most helpful coolers mods to do.

For my design I overcomplicated things and created a push-button switch that turns on 5 LEDs that I drilled and glued in place in the lid. If you're feeling ambitious you could do this and improve the design by wiring these to run off of the 18v drill battery for the blender. The electrical guru's will probably let us know the easiest way to go from 18v to 3 volts using some sort of Switched Mode Power Supply (switcher). I cheated and used a two AA batteries which if I remember to turn it off between uses should last for a few years.

The EASIEST way that is nearly as good it to pick up one of these pressure activated Dot-It lights from Sylvania. They turn on with a simple push and you won't need to disassemble anything is you need to change the batteries.

Twist open the battery access cap and here's what to do. Drill at least 2 holes in the battery cap of the Dot-It the size of your pop-rivet, let's say 3/16". Line up the lid where you want light and mark and drill the holes on the inside of your cooler lid.

Pop-rivet the lid in place and screw the Dot-It light back on. Now you've got a nice bright water-resistant light inside your cooler. Shine on!

Step 10: Cooler Gear Cart

Having a cooler with wheels that you can't carry anything else with is like having a friend with a pick-up who won't help you move. Unacceptable.

I modified my Coolest to carry my extra gear to and from my car to my outdoor event. The tie-down is a loop of 3/16" bungee shock cord that wraps around the handle of my cooler when not in use, but locks down through a set of clam-cleats.

This set up should work with any cooler that has an extendable handle like mine does. 3D print the three parts for the Tie-Down and here's how to install them:

First, you'll need to drill and pop-rivet the clam-cleat and cord-holder to the back of your cooler in between the handle. I probably went overboard with the pop-rivets, but they are just so efficient and fun!

Next you'll need to install the lid-lip tips. These give your cord something to wrap around when you tie your gear on. Place these close to the edge as shown in the pictures as you still want to be able to easily grip and open the lid. More pop-rivets please.

Thread your shock-cord through the clam-cleat holes from the top down. You may need to melt and shape them to easily fit though the holes, or use a set of needle nose pliers. Now we need to figure out the size of our tie-down loop.

Take a look at the second picture and observe how the cord loop is stored when not in use. You want your loop to be very slightly stretched when in this position. I joined my cord together with a crimped piece of brass tubing I had lying around, but nothing is wrong with a simple knot.

When you place your gear on top of the lid you can simply tension the shock-cord and lock it in place using the clam-cleat. You'll be amazed how much gear you can secure with a loop of this size, and the great thing is that it's always there!

Step 11: Never-lost Bottle Opener

Your teeth. Your keys. Your lighter. Your wedding ring. The curb. The
car bumper. From this day forth, these things need not ever again open your beer.

When you install a bottle opener on your cooler you’ll never have to ask for or lose one again.

I ended up installing two bottle openers on my Coolest prototype because I wasn't sure which one I'd like more.

The simplest one is to simply order the one I listed on the parts page (black one) and install between the handle on the back of your cooler. It's easy, works great, and always there. The only disadvantage is you need to remove a drink from the front of your cooler, then walk around to the back to open. Lazy complaint I know, but many times the cooler gets placed up against something at an outdoor event and then this is not ideal.

The second method lets you grab a drink and open it in almost one fluid motion, however it does leave the cooler open longer.

The second method is easy as well, and has the added advantage of automatically catching all your bottle caps. You can pick up this bottle opener:
...and install it in the lid of your cooler.

First you'll want to drill two or three 3/16" holes in the opener. As this product is stainless steel make sure you have sharp bits and use a slower rpm.

Mark the hole locations in the lid where you want your opener to mount, and also trace around where the bottle cap inserts. You need to cut a hole slightly larger than the bottle cap opening so your bottle cap will go into the opening.

Use your trusty pop-rivets and secure that bad-boy in place. Now you have a bottle opener you'll never lose again.

Step 12: The Coolest Cooler Progression

Here are a few pics of the process this cooler creation has gone through. As I said I made the Beach Blender and Cooler-Blaster years ago, but they finally were ready for an upgrade.

I've been meaning to create an Instructable of my own for years and that's how I started off this summer. There is so much room for improvement in coolers today I hope everyone adds at least one of these features to your own cooler. Make sure to share your pictures below. I do have a patent pending on a number of these features, but as long as you're not selling your cooler creations you are more than welcome to make your own. :)

Here are the links again to each of the mods:

I decided to try to bring it to market on my own through the Kickstarter platform. You can check out my campaign here:

I've also entered this project in the Outdoor Projects Contest, so please vote for me if you think any of these cooler mods would improve your next outdoor adventure! Thanks!!

Instructables Outdoor Projects Contest

Grand Prize in the
Instructables Outdoor Projects Contest

Be the First to Share


    • Big and Small Contest

      Big and Small Contest
    • Game Design: Student Design Challenge

      Game Design: Student Design Challenge
    • Make It Bridge

      Make It Bridge



    7 years ago

    Where can i buy one of these


    Reply 7 years ago on Introduction

    I got one off the kickstarter, but looks like they will go on sale in July. Here is the signup for it Then again this is still technically in development so there could be delays. I am super excited for it.


    8 years ago on Introduction

    what did you use for the upper housing for the blender. the housing you glued into the cooler


    Reply 8 years ago on Introduction

    3D printed part modeled off of the blender pitcher I had


    Reply 8 years ago on Introduction

    FYI. The files for me to download for blue prints and template don't work. The only one that works is the one of the circle template


    8 years ago on Introduction

    Super famous:


    8 years ago on Introduction

    I just saw your Kickstart campaign as well and I too thought I saw your Instructable about it- congrats on the successful campaign! Happy to see our fellow makers and inventors kick it up a notch! *high five*


    8 years ago on Introduction

    Just seen the Kickstart campaign, doing the rounds on facebook!
    I thought to myself, Hang on, someones nicked an idea I'd seen on here - Good luck!


    8 years ago

    Sweeeet! Ur a camping genius ;)


    8 years ago on Introduction

    Please let me know when you start production on Coolest. I can think of at 20 vandwellers who would love this cooler.


    Reply 8 years ago on Introduction

    You've got it! We're actually gearing up right now to re-launch our Kickstarter end of May. In fact I'll be sharing the new production design this next week and it is seriously the Coolest looking cooler ever. Add your email to and I'll keep you posted.

    Thanks also for the idea of the Vandwellers market!


    8 years ago

    just curious I didn't see if you said it or not but how much did it cost and how long did it take you


    9 years ago on Step 6

    You might want to look at using an LED Infrared detection light like this one from Lee Valley Tools. I use one in my small bar fridge and it works great. The light comes on as soon as I open the door, no switch to push on or off. I love this project. Lots of very good work here.


    9 years ago on Introduction

    Smart ideea, COOL cooler, hope to make good money with it and for you and your friends just: READY, SET, PARTY!


    9 years ago

    Question ? On the 2nd method for the opener , How do you get the caps out of the lid? Is there a door on it or do they just stay in the lid ?


    Reply 9 years ago on Introduction

    The entire lid can't actually fit through the opening there so they end up just falling into the cooler. You could put a magnet back there to hold onto each cap if you were so inclined.