Passed Mechanical TFS First Try - Here is what I did to pass.

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I recently passed the Mechanical TFS PE exam on my first attempt, and I wanted to share my experience in the hope that it helps others—just like so many posts here helped me along the way. I promised myself that if I passed, I’d come back and write a full breakdown of my journey.

What follows is a summary of what worked for me. Don’t feel discouraged if your approach looks different—some people study more, others less. I constantly felt either ahead or behind depending on what I read here. Just remember: this process is a mental game. Take it one day at a time, and know you’re not alone in feeling unsure or overwhelmed.

My Background

• ~8 years out of school
• Passed the Mechanical FE last year
• Took about a year off afterward, then started studying for the PE
• My day job has little to do with TFS material—so I didn’t have the “I do this at work” advantage

Study Tools and Strategy

I used the 16-week On-Demand Slay the PE course (Mechanical TFS). My company paid for it, so I didn’t submit homework for a refund. Here's how I approached the course:

Videos and HW Problems

• Watched every video, taking notes.

• Printed the homework PDFs and opened the PE Reference Manual on my computer.

• Attempted to solve problems using only the PE reference manual.

• If I got stuck, I’d force myself to struggle for 5–10 minutes before peeking at solutions. This helped me better retain the concepts.

• It took me 19 weeks to finish the 16-week course because I took my time to truly understand the material.

• I kept a notecard with the hardest 1–2 problems from each homework section.

  • This helped me track concepts I needed to revisit later.

Quizzes

• These were tough—especially on the first try.
• My first quiz scores were often 50–60%.
• I took a screenshot of every quiz problem I missed (without the solution) and saved them in a folder for review later.

Once I had finished all of HW, quizzes, and the Slay Practice Exam (dsicquised as HW), I moved on to Tests A–D. Same process:

• Logged every missed or difficult problem onto my notecard.
• At the end of this phase, I had 26 tough problems.

I then created a custom "mini-exam" from these 26 questions:

• Used SnagIt to compile, printed a few copies.
• Timed myself at 6 min/problem.
• Repeated the mini-exam three times, focusing not just on getting the right answer, but truly understanding the approach.
• Important: Don’t just memorize solutions—understand them.

wholehearted

In the final month, I focused heavily on:

• The NCEES practice exams
  • First attempt: 68%
  • Second attempt (after two days): 74%
• I reworked both the Pre-October and Post-October NCEES practice exams three times.
• Slay practice exam problems were reviewed again—some more than 10 times.

I didn’t track Slay Practice scores since I’d already seen many problems during the course. But by test day, I felt reasonably prepared—though, like many, I still worried about getting a version of the exam I couldn’t pass.

Key Takeaways

• Struggling is part of the process – let it happen. Try a problem, fail, then go back and rework it until it clicks.
• Don’t follow the schedule rigidly – if a topic needs extra time, give it the attention it deserves.
• Watch YouTube videos for tough concepts: Topics I needed extra help on:
  • NPSHa & pump curves
  • Psychrometrics & HVAC terminology (SHR, latent/sensible heat, economizers, etc.)
  • Combined cycle plant walkthroughs
• You don’t need to master every topic to pass. I never fully grasped mols/mass/mole fractions. I decided to skip them. If I saw one on the test, I just guessed and moved on.
• The last 4 weeks are critical. This is when your effort can make or break your chances. Re-solve problems until the steps become second nature.
• Know the reference manual inside and out. This cannot be overstated. You should be using it constantly while studying. By test day, you need to know where to find tables, equations, and concepts without hesitation.

Final Thoughts

This exam is passable—even if you're years out of school and don’t do TFS work daily. Stick with it, embrace the struggle, and focus on building deep understanding instead of shallow repetition.

Feel free to ask questions—I’m happy to help however I can. Good luck to everyone on their PE journey!

Lastly, I would wholeheartedly recommend SlaythePE for anyone looking to take the mechanical PE exam.