What does a mechanical engineer actually do?

In this blog article, we are taking a deep dive into the wonderful world of mechanical design, as we strive to answer the question posed in the headline. The best person to answer is, of course, someone who works as a mechanical engineer, so we asked our mechanical engineer, Matias, to talk about his job in a diary-style blog.  

Coffee to kickstart an engineer’s brain

This engineer’s morning usually starts at around 8 a.m. One good part of flexible working hours is that you can start your workday at your own pace after you have enjoyed your morning cup of coffee. However, the thinking and planning start while the coffee is still in the cup. Considering the priority levels and workloads of ongoing projects determines how the coming day will go. This morning, I have decided to leave my remote workstation and go to the office for a change, because I might need to build a prototype in the evening if the last parts arrive. At the office, I sit at my desk at 8 on the dot, since I should finish a recently started project’s materials before a meeting at 9. The 3D models need to be in presentable form because I have the first review meeting with the client in the early part of the morning.

8.00 a.m.–9.00 a.m.: Documentation and finish up a project

The project has only started, but I have finished the first 3D model, which makes it possible to see the potential look and manufacturing method of the product. At this point, it makes sense to have the first review meeting, so that the client’s needs can be accounted for as well as possible. For the presentation, I paint some components in the 3D model with different colours to make it easier to explain certain functionalities. At the same time, I add nuts, bolts, and other attachment tools to the model. Polishing such details makes the model more visual, and they also make it easier to estimate the size and feasibility of the product on a computer screen. Once the 3D model is ready to be presented, I make a PowerPoint presentation that includes initial information and matters that require further details. A well-made presentation helps the meeting run more smoothly and ensures that we cover everything we need to.

9.00 a.m.–10.00 a.m: Review meeting

The meeting is held remotely because the client’s office is located in Southern Finland. The client seems excited since this is also their first time seeing how the list of requirements and other initial information from the beginning of the project have come together in a 3D model. The meeting covers the designed product, one segment at a time. We also ensure that my vision of the product aligns with the client’s vision. Some areas of improvement are identified during the meeting, so I carefully write everything down in my meeting memo. During the meeting, we also come up with a couple of brand new ideas for further development, but they are put on the back burner and given time to develop for now due to the client’s busy schedule. The meeting is concluded with a good feeling, knowing that we are heading in the right direction and that we can continue the project as planned. Next up is making the changes discussed at the meeting. The next meeting is scheduled towards the end of next week.

After the meeting has ended, I take a small break to stretch while I get some coffee. When you mainly work on the computer, an ergonomic workstation is not enough. You also need to take breaks and have a stretch every once in a while, to stay energetic. This is easy to forget when working from home when you are really focused and immersed in your work. At the office, your co-workers will occasionally remind a plugged-in colleague to take a coffee break.

10.10 a.m.–12.15 p.m.: 3D modelling

The day continues with 3D modelling, which is the most common part of a mechanical engineer’s job. Things brought up in the previous meeting include reducing the overall weight of the product, which is what I start working on next. The device model that I just presented had been designed with steel plates as the frame. However, the client said that the overall mass of the device was too big, so I start thinking of alternative materials or whether we could make the frame from steel plates that are a bit thinner. This type of task combines an engineer’s knowledge about manufacturing methods and materials with my own experience and practical skills in the technical field.

When choosing materials, you must account for potential manufacturing methods and costs to ensure that you choose a sensible material that suits the use purpose. On the other hand, you need to think about what the device will be like as a whole, which parts will be attached to one another, where most of the load will be concentrated, and so on. You always have to consider the entire product. In this case, choosing a lighter material may make the structure too weak, which means that the device might not be able to bear the weight of the components installed inside the device.

I wanted to optimize the device’s frame structure so that the most important parts are still made of steel, but the material will be made slightly thinner. Making the material thinner is the most sensible option in this case because making the planned parts thinner will take significantly less time compared to designing a new frame structure. 

I want to make sure that the thinner structure is durable by carrying out a simulation that tests how the structure would behave in reality. In the simulation, you define the attachment points, the location of the load and its weight, as well as other initial information. After that, you can perform a “virtual test” on the structure’s durability. The result reveals information like how much the parts might bend and whether the structure has some area that would bear too much of the load. A simple simulation indicates that there is one area where the load is too high, so the parts in that area should not be made thinner. Otherwise, the device’s plates can be made thinner, so the device’s overall weight can be reduced quite a bit.

After editing the parts, I carry out a new simulation to make sure that the structure can bear the necessary loads without issues. The weight will also be reduced by changing some of the less critical steel plate parts to aluminium. For example, the protective case that will be placed on top of the device and the simple plate parts inside the device can be easily changed to aluminium, as their purpose is only to protect the components inside.

12.15 p.m.–12.45 p.m.: Lunch break

After the clock strikes a little past midday, a colleague reminds me about lunch. While eating, the discussion quietly shifts to work-related matters, but that sometimes happens with people who are passionate and excited about their work. The topic of discussion stands tall at the workstation next to the lunch table: a prototype of a device designed for a factory environment, waiting for the final electrical components to arrive. The sturdy frame made of machined aluminium parts is not very large, but it will hide within it optical devices and other technology, all designed by us ourselves.

As I return to my workstation, I glance out the window, and as if someone read my mind, I see a familiar delivery vehicle drive into the yard. The prototype’s final components have arrived, so I can finish the assembly. With that, the rest of my day changes from computer work to prototype assembly. I go to check that the design work I did was saved and then start assembling the prototype.

12.45 p.m.–4.50 p.m.: Building the prototype

The frame of the prototype was assembled earlier, so now that the final parts have arrived, it is time to install the parts that go inside the device. The work is mostly installing electric devices and their attachment parts. Although I know the device that I designed thoroughly and the frame has clear places for the components, I print the device’s blueprint next to my workstation to make sure that I assemble everything correctly. This is also good practice for how the order of assembly that I outlined on the computer works in reality. It is rare to get to both design and assemble a device, so this is a good opportunity to develop my skills comprehensively.

In addition to attaching the parts, I also connect the electrical parts. To do this, I go through the device instructions and technical information to make sure that all cables are connected correctly. when making the 3D model, you do not always think about how many parts the device will have inside it in the end. This is thankfully general knowledge, so during the design process, the parts were designed to leave lots of space for cables. The extra space increased the exterior measurements a bit, but it really was necessary during assembly because the cords that came with one electrical device were much thicker than expected. This is not a problem, however, because it was taken into account in the initial design process.

Hobbies help you stay motivated at work

It is almost 5 p.m. as I run power through the device for the first time. All electrical devices seem to work as they should, so this is a good point to stop for now. Tomorrow’s tasks include connecting and programming automation devices, for example. Once the prototype is finished in the coming days, we will first thoroughly test it ourselves, after which we will arrange a meeting with the client for official testing.

I do not want to stop in the middle of work, but you should not stretch out your working day, especially since this project’s schedule does not require rushing things. It is good to give your brain time to rest. Even though the work is not physically very taxing, constant cognitive work goes most smoothly when you are well-rested. This engineer likes to take his mind off work with music and exercise, which makes it easier to come up with new ideas the next day.

As the above description shows, the work of a mechanical engineer is not just 3D modelling. Depending on the engineer’s skills and interests, it can also include many other kinds of work. Are you interested in working as a mechanical engineer? Follow Optotec’s LinkedIn page, and you will be the first to know about open positions!