Milk Frother Disassembly

Our product testing began with the Ikea ($2) milk frother. First, we had to put in the batteries because it didn't come with any. This took some effort because the battery slot was not smartly designed at all.

Battery hinge design flaw

The hinge of the battery cover blocked part of the opening, which made it difficult to get both batteries in. The overall design of the device was also lacking. It felt cheap in your hand, with a thin spray painted plastic body, and flimsy rod. The frother had no grips, just smooth plastic. The on/off tab felt like it would break easily.

Ikea milk frother did not feel like a quality product

                                     

Despite the aesthetics, the frother actually did its job really well. It was produced to agitate the milk and create air bubbles. This creates a thick froth. It aired up the milk nicely and only took around 30 seconds to do so. Also, the air bubbles in the milk did not collapse very fast (<5 min). The frother didn't splash the milk everywhere, which was nice, but then again, it didn't have a very powerful motor. 

The product has the following strengths and weaknesses:

Advantages	Disadvantages
Cheap	Flimsy design, could break easily
Easy to use and clean	No advanced features - some simple features are clumsy
Does its job-frothing	Not a status symbol
-	Doesn't feel good in hand
-	Hard to put in batteries
-	Not much power

When you first turn the device on, you can feel/hear it vibrating in your hand. Meanwhile, the rod and metal "spring" rotate, indicating that it is powered on and ready to agitate your drink. Based on these cues, the device affords to froth, and does so. However, if the device is not turned on, it is difficult to see what it's purpose is, if you don't know beforehand. Also, the slide switch that turns the device on does not afford rotation. It is a slider that is slid upwards to turn on, and therefore lacks an apparent mapping.

Chocolate milk after being frothed with Ikea milk frother 

The next step was to disassemble the frother. This took place in the following steps:

1. Battery cover removed (unhinged).

2. Metal frother attachment and silicone plug removed.

3. Rod pulled off.

4. Plastic casing opened (with the help of pliers).

5. Small internal metal components and DC motor removed.

It was easy to pull everything apart except for the two plastic halves of casing that were latched together. The inner components were surprisingly simple and standard - especially the motor. It looked like something that would be very easy to copy. It would be interesting to see how they protected their design.


The device only has two "states" - on and off. It operates using a slide switch. I knew that when you slide the switch forward, the circuit is completed, but I wasn't sure exactly how it worked. I found some good images explaining how it functions:

Inside a slide switch, "see saw" mechanism : http://www.engineersgarage.com/insight/slide-switch?page=4

I'm pretty sure this switch is a lot more complex than the one in the Ikea milk frother, because I didn't see any springs or small plastic parts. But I imagine it's the same concept where a piece of metal is pushed downward onto a contact point. The "pins" on the bottom are also apparently soldered - but I didn't entirely understand that part.

The parts were easy to lay out in order:

Ikea milk frother disassembled

We then brought out the higher end milk frothers for comparison. One thing I noticed was that I didn't realize how weak the Ikea milk frother's motor was, until I tried the $20 milk frothers. They had thicker casing, were heavier in the hand, and seemed more waterproof with thick silicone spacers.

According to goodhousekeeping.com, milk frothers should be judged based on the following criteria: how well and how quickly they froth both whole and nonfat milk, how easy they are to operate and clean, and how stylish they are sitting on the countertop. Based on these criteria, one of the higher-end devices would win, especially when it comes to style. They would also win if judged based on the "feedback" the device gives to the user. The higher end models had more powerful motors (same amount of batteries), which eludes to better froth, and were heavier in the hand, which is indicative of durability. 

After disassembling this device, I had a deeper understanding of how the internal components interacted. It was especially helpful to list each part and its interface to see the context of each part. I also was able to guess the materials and manufacturing methods for each part, which helped me think if the device from a perspective other than the consumer's.