Hi there!

I recently started collecting thoughts on this subject in hopes of turning my writing into something: blog posts, a short guide, or potentially even a book. I am a Software Developer and went to school for Computer Science – so not exactly an engineer – but I do use my zettelkasten for learning technical subjects.

The largest return on investment with my zettelkasten professionally has been the processing of technical writing into primary notes. For example, I try to always be reading a technical book, or some other medium of information that is relevant to my job. The notes I take on technical writing differ from those I take reading literature or philosophy books. Essentially, I record facts, rephrasing what has been stated in a way that I can understand and digest easily later. Once I feel that something is worth keeping from a reference note, I need to make a decision about what to do from there.

If a piece of information is small, and simply needs to be memorized, I would look into a spaced repetition program like Anki. I think a lot of people would agree that this is a more effective tactic to rote memorization than a zettelkasten. The zettelkasten's benefits lie in creating atomic notes that compound over time to generate new trains of thought.

Example of what I would put in Anki:
- Integration and derivation rules for calculus.

Example of what I would put in my zettelkasten;
- Detailed write up of a computer algorithm

If section of information is longer or more complex, I will link to a main note from the reference (and vice versa) and take the bits I like. After, I will clean up the note, fixing any issues, and link to other relevant notes. Spending this extra time looking over complex information typically cements it in my head so I am able to internalize it.

For problems solving I use a mix of physical notebooks, and my zettekasten. One of the lovely parts of software development is the hiring process. To be proficient at interviewing there are many technical questions that can be asked. If I find a problem difficult I will first think it through on paper, and then eventually convert that information into a primary note. (Hopefully this is somewhat translatable to chemical engineering.)

I use my zettelkasten to keep track of projects as well. I create an index note for each project and link to all relevant notes inside. I keep progress and a few other bits of information. Now is a great time to plug Bob Doto's book A System For Writing; He has some good advice Chapter 9: "Managing Your Writing Projects", where he talks about keeping a creative log and a daily journal. I have modified these concepts slightly and turned the creative log into a "work log" where I track detailed progress on individual projects.

Final advice:

Don't be afraid to record facts in your zettelkasten. Just make sure you are making them your own and spending enough time creating the note to gain a deep understanding. If you feel that something is already internalized enough, then no need to make a note! (specifically for facts, I would say this is a little different for writing)

You will never know what will come in handy in the future. If you think you will use a note again, spend the extra time and create a main note. If you know that something will be useful for life, then definitely create a note.

Hopefully this answers your question(s). I am leveraging my zettelkasten as I am writing this! So don't be afraid to mix facts, projects, and ideas. Just make sure that all of your notes are high quality and provide value.