Why Starting A Rocket Engine Is So Hard!

Today we’re going to do a deep dive on how exactly you start a rocket engine. We’ll cover pretty much everything from a simple solid rocket motor, to all the intricacies of liquid fueled rocket engines.
We'll go over thermal conditioning the engine, the spin up process, the scary transient regions, and the actual ignition of the propellants. Then we’ll talk about some of the extra challenges like starting a rocket engine in space and then we'll go step by step through the RS-25's startup procedure.
More of a reader? Check out our article version that also includes some links and sources - everydayastronaut.com/how-to-...
Timestamps:
00:00 - Intro
01:55 - Recommended Pre-Requisite Knowledge
02:35 - Starting a Solid Rocket Motor
05:45 - Purging And Thermal Conditioning
13:45 - Spin Up
20:55 - Transients
24:10 - Ignition
32:40 - Starting A Rocket Engine In Space
38:20 - Step By Step Example
53:15 - Throttling And Shutdown
57:10 - Summary And Final Thoughts
"Space Shuttle Main Engine" by Robert E Biggs - amzn.to/3J0VdKo
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[@austingirdner92]

All of this in less than an hour is definitely not a long video. I'm honestly impressed you were able to cram this much into an hour!

[@Scott_C]

Each peace could easily be 30 minute video and a month long series..

[@loganhumphries4851]

@@Scott_C or even a college class

[@patricktho6546]

@@loganhumphries4851 nah, a lot of theory is missing for university and even the step before

[@LQB42]

Super impressive isn't jt

[@TheDrumrhythm]

Wait, that was an hour!? Woof

[@mixsmasher]

I think we can safely say this is one of the most anticipated videos that everyone wants to watch. Thanks for all the effort you and the team put into it! 😊

[@LQB42]

I showed my dad and he said he doesn't care 😔

[@marylizbender]

I second this!

[@mixsmasher]

@@LQB42 when I said everyone I meant of his subscribers, your dad doesn’t need to care everyone has their own interests🙃

[@LQB42]

@@mixsmasher he doesn't talk to me about things I like he only wants to talk about family

[@risharehraje793]

I just start watching and I'm super curious if we will finally know how does Raptor 2 start.... For now it is mystery.

[@ShadowZone]

Me, an hour ago: "Yeah, rocket engineering is complex, I know." Me, after watching this: "Holy cow, how did they ever manage to NOT blow up every single space shuttle on the pad?" Great, informative content, Tim! Thanks for this.

[@JoseNovaUltra]

Love your channel! happy to see you here.

[@Loanshark753]

Maybe Rocket lab chose electric fuel pumps to reduce engineering challenges.

[@alanm8932]

Yeah, it does make it even more amazing that the V2 rocket managed to be pretty successful 80 years ago. I guess the hydrogen peroxide powered pump made things much simpler, if less efficient. The fuel wasn't cryogenic but did they precondition the liquid oxygen pump? Was it just built strong (& heavy) enough to withstand pressure surges at startup?

[@michaelschnittker7388]

@@Loanshark753 Rocket Lab circumvented about HALF of the complexities by going with battery powered electric motors to run the fuel and oxidizer pumps vice using the propellants themselves which is literally an almost one hundred year old 1930's approach. I cannot see why there could not be a combination of the two, use electric motors to get the pumps running and the engine started THEN chuck the motors and batteries on the way up to save weight and let the pumps run from turbines like "normal" by burning internal fuel and oxygen to spin turbines, BEST OF BOTH WORLDS. It would eliminate a LOT of hardware. And hopefully at some point in the future batteries will be sufficiently robust to run the pumps with electric motors ALL the time.

[@Mawyman2316]

@@michaelschnittker7388 Except when you get to the part about chucking, it fails, and crashes into your rocket destroying your lower stage. I think we should just put a little wind turbine under the rocket and have it spin with the propulsion. No way that could go wrong.

[@anthonyblacker8471]

I'm just at the beginning, but Tim, brother you have really taken your love for rockets (all of it) and come SO FAR!! You have assembled the highest production quality team of genius people and so much talent on your team Tim, wow. You're SUCH a GREAT filmmaker!! You really deserve whatever fame and glory you have gotten and will continue to get. I'm amazed every video you create for us all to enjoy free. Thank you SO much for the hard work, all the sleepless nights, the long hours, just to share your experiences and learned knowledge with us on KZbin. You're one of a kind Tim.

[@EverydayAstronaut]

Thank you so much for the kind words. I appreciate it immensely! I'm glad the passion shows 🖤

[@Trrenik0kb]

he deserves to go in space for free.

[@ibleedblue1101]

This comment sums up exactly how I feel while I’m left to delve into my newly found passion for rocket engines. Thank you

[@kookieinsd]

Can all this information be found on the internet? Or do you need to have a SPECIAL team with VERY INTELLIGENT people to make a video or learn something like this?

[@JoeLaFon3]

Gaaaayyyyy

[@AtubewatcheR]

I CANNOT believe this is free. Thank you Tim for everything you do. This is incredible and an entire generation is learning about space travel because of you. 🙏

[@BravoNineThreeTwo]

There's nothing 'free' about the ad-revenue e-commerce model. You are the product, my friend. Awesome content though, Tim.

[@neon_Nomad]

@@BravoNineThreeTwo whats an ad

[@geulach]

Sponsored by Apple watch

[@BeaverZer0]

Coming to you by whatever ad I didn't see using premium.

[@harmankardon478]

not free bud

[@srun121]

I'm waiter. The fact that I sort of understand the engineering behind rocket engines because of the work you do is kind of insane. This is some of the best educational content out there. Beautifully explained and produced. You are a legend, my friend. Keep up the good work

[@kevfluke1]

🎉❤😢

[@nguyen4566]

Like many of you, I’ve already watched the 2 videos recommended. The “Everyday Astronaut” deserves a flight to the moon and back home safely. I’ve learned so much from this channel.

[@Titter2]

I've been watching this channel since you were just live streaming Spacex launches from your house. To see how far you've come in such a short amount of time is quite incredible. I've learned so much in the years I've watched. Hard work surely pays off, keep it going friend.

[@cseblivestreaming8073]

„Ferb, I know what we‘re gonna do today“

[@dannybell926]

What's that Phineas?

[@ThePixelated_kris]

Underrated comment

[@altair1405]

You are so busted!

[@Scott_C]

Where's Perry?

[@cseblivestreaming8073]

@@steveschritz1823 following this, we get a great doofenschmirtz flashback-type backstory where he talks about his uncle, Werner von Braun, who was too busy with his rockets to ever attend one of his birthdays

[@rogue6]

Incredible video as always, Tim. The graphics used here are second to none, and your dedication to communicating the science of spaceflight to the general public is absolutely amazing. Keep it up!

[@ScottRainey]

Icing on the cake: Clips from Tim's earlier interviews with actual space entrepreneurs, and not just Elon Musk, which was in itself a huge journalistic score.

[@Gupp1s]

As an amateur rocketeer who has been attempting to make a funtional liquid fueled model rocket for 3 years now, this video is invaluable to me. Thank you so much Tim, the work you do to make this information more accessible is amazing. Keep it up. PS: I can't wait to join you in losing our minds over the first full stack Starship launch, I'll be watching live even if I have to take an extra break at work.

[@thothheartmaat2833]

LEARN HOW TO SPELL FUNCTIONAL CORRECTLY FIRST.. NORMALLY IM NOT A GRAMMAR NAZI BUT IN TERMS OF ROCKET ENGINEERING WE CANT AFFORD TO BE MAKING THESE KINDS OF MISTAKES.. ITS LITERALLY THE DIFFERENCE BETWEEN SUCCESS AND FAILURE..

[@Bpace777]

That RS-25 start up is insane!

[@chilliadmiralportsmouth221]

Your channel iterations since 2018 are beyond admirable, Tim. This takes the space biscuit. Well done mate.

[@Rojasher25]

This is why we wait so long. Thanks for the incredible quality Tim! 🚀

[@SapientPearwood]

This is an awesome video, great job!! I'm a propulsion fluid dynamics expert at NASA, and I learned a bunch from this! Some of the folks I work with are involved with RS-25 startup, and it's really cool to see their work showcased so publicly like this. Also, I'd love to see a video on engine throttling!! You could go through solid rocket grain shape, in-space thruster pulsing and impulse bits, and of course the wild world of launch vehicle engine throttling and deep throttling. Great topic to add to your growing collection of incredibly informative rocket propulsion videos.

[@feldamar2]

Transients suck. So lets put a transient inducer into the sucker!

[@ikeraguirre5865]

ER-42 at Marshall?

[@michaeltaylors2456]

So much complexity and yet zero failures to start on any mission once in space, kudos to the engineers.

[@rocketpunchgo1]

Easily one of the best space engineering channels on KZbin ever. Keep up the great work Tim!

[@jonnylakewood7767]

Tim, I feel like I finely understand rocket engine power. I have been fascinated since I was a kid in the early 60's but no matter what I read, I had never really been inside a rocket engine, until now. Thank you for doing your homework and explaining it so well. Your interviews and deep-dives with rocketeers are gritty and enlightening. Also, I appreciate all the work you did to put this video together.

[@edmondthompson1523]

This excellent content is why you are on the Dear Moon team! Thanks for doing this!

[@nankinink]

As a programmer, it sounds like rocket engines are like multi-threaded applications where each word could lead to a explosion instead of error messages. Insane and really well done lol

[@MordecaiV]

It's so rewarding to see you able to draw from your years of dedication to get the _perfect_ examples to use as B-roll/explanation shots. Great work.

[@TheSfyfe]

Tim, this is easily one of the best videos you’ve published to date. You truly captures that feeling I used to get watching the discovery channel when learning something new and fascinating! Thank you for all you and your team’s hard work in creating these deep dives!

[@dizzyizzie6354]

You must be extremely old! Do you remember that other channel called "history"..? I'm just joking, but honestly KZbin has gone from low quality sub 10min "nonsense". to having the best, incredibly in-depth, educational "content" that exists today. In literally every subject / niche. ( Some Premium & Paid subscriptions are okay, but) TV entertainment models. high cost production, decompressed , fluffed or dragged out & interrupted delivery. Low information destiny, or low/no amount of educational information, either to fundamentally or completely understand. & actually learn anything at all. In a limited frame. Tim is probably the most influential or best of educational, space/rocket, creators! I'm so happy he won dear moon contest! He has continually improved & multiplied content quality so consistently. I say he can't get any better yet he does!

[@ScottRainey]

One of the best? I dunno. Top 100 surely. Nearly every explainer Tim does, is simply awesome at taking twisty complex stuff and making it clear, often simple. I know what you meant though. Hard to select the right superlative when every effort vastly exceeds expectations.

[@chuckvanderbildt]

This is a very impressively structured and researched video. Amazing work, Tim.

[@robjchristopher]

Fantastic content Tim - huge congrats to you and the team responsible for making this happen. Fascinating stuff.

[@TheMusaic]

Excellent work, once again! Thank you, I learned a lot! One last thing, as a retired professional aerospace engineer, I am super-impressed with your deep dives. Takes real effort to absorb all of this material and you have real talent!

[@andrewrowe5224]

Wow! Knocked it out of the park as usual! 'Appreciation' is the word. I had no idea, and Tim, you're absolutely right. Developing a rocket engine design to the point where it can be reliably fired up is a very impressive feat. I did not appreciate this previously. Thank you 😊

[@choppythechimp1567]

I've been watching science/engineering videos on YT for years and just found this channel?? It's second to none.

[@BLKBRDD]

Videos like this are why I donate to this channel. It’s inspiring, fascinating and I feel the collective passion of everyone involved in making these videos. Never stop inspiring 💪

[@CameronMakesRockets]

Thanks for the HUGE amount of effort on this video! You and your team are producing very high quality content and I can’t thank you enough!

[@pythosdegothos6181]

Crazy how complex a process that happens in seconds truly is. Thank you Tim.

[@CSIStarbase]

So many questions answered! Awesome video Tim! I'm glad I was finally able to watch this

[@fardreamer1576]

It's truely impressive how much information you packed into one video while also explaining it that well. You make it so very easy - relative to the complex nature of the topic - to understand. Thank you!

[@thespacepeacock]

I would love to see more videos about rocket engines! You really make these extremely complicated subjects feel understandable and intuitive. Well done Tim and team!

[@jimalbi]

Another great encyclopedic video. I had to pause and rewind a lot to follow up because there's so much in it.

[@sixstringedthing]

I will never get tired of watching RS-25's spin up in slo-mo and seeing the engine bells resonating like literal bells in sympathy with the initial shockwave when the engine transitions from pre-burner to full flow. Then watching the boundary layer spread out across the nozzle wall as combustion stabilises. So impressive, I love it every time.

[@zaf_nz]

I gotta say I absolutely love that you provide accessible content by means of having this as both written and video form. You're a star!

[@sjwatt]

Super high quality presentation! Thanks so much. This seems about as deep as you can go without losing half the audience along the way. Amazing job

[@thomascharlton8545]

What an incredible job you've done with this! This series you've created on the fundamentals of rocket engines will be so useful to so many people. Thank you Tim Dodd.

[@liver.flush.maestro]

Wow, beautiful diagrams of this RS-25 startup sequence, you really put a lot of effort into this video; congratulations!

[@tcf70tyrannosapiensbonsai]

What a superb presentation of this complex issue. From storytelling to infographics to anything else, I'm impressed! Thank you very much.

[@kinuorthel8096]

So grateful for this, have been following you and Scott for a while and neither of you had (I think) explained this process so comprehensively, thank you!

[@Drflamerock]

Fantastic video!!🎉 amazing graphics demonstrating the startups. Very grateful for all the work you and your team put it. Thank you Tim🙏

[@GOVAUS1]

Tim, what you have created does benefit all of humanity immensly. Everyone can bite as much as they can, but overall we all win. Thank you for everything you have done. This is a truly excellent episode. For older folks, just imagine how many libraries you'd have to visit to get 10% of this episode in 80's or so.

[@WuffiePhoenix]

Awesome video, Tim. I'm fascinated with rocket engines and this was, while complicated, probably the best explanation I've ever heard.

[@iwayini]

What a fantastic video! Editing was excellent. Transition between was sections was seamless with no long pauses in the script. Very well done Tim and team. The hour went by very quickly indeed.

[@russellharbin8020]

Tim, nice job as usual! Very informative and presented in a way that is easy to follow. You truly are the Everyday Astronaut bringing space down to earth for everyday people.

[@nickledeposit]

I just absolutely love these videos and appreciate the command of the subjects that Tim shows in such little time. I look forward to many more of these deep dives and learning much more.

[@ScottRainey]

OMFG! 200k views in just 2 days on a DEEPLY geeky topic? Tim, you totally rock as a tech explainer! Separately, it is very impressive that there are that many people on earth who want to watch this. A measure of someone really understanding something, is the ease with which they explain it in relatively simple words. Bravo!

[@TiFredTheBest]

I’ve been waiting for this one! Thanks for all that you do Tim !

[@njits23]

Oh boy. One hour of rocketry. I'm excited.

[@ollimartikainen]

Tim this video is a work of art and I'm sad for humanity that it's not getting that much views. Don't let that get you down tho, this actual document is something you can be proud of.

[@sr71kartik]

This is just incredible Tim. I hope you continue making such videos because these subject specific videos are what hooked me to your channel in the first place. I love the content with space startups as well, but this is what I wait for. Maybe try getting these companies to contribute to your videos in any way they can?

[@mozzerellaman]

Thanks for always creating content of such incredible quality!

[@Cardroid]

As usual.. very well done! What a tremendous gift you are providing for kids of all ages wanting to learn.

[@Gibson99]

Amazing work, Tim, Caspar, & team! I'm a space nerd, and I watched the previous videos and Scott Manley's video on rs25 startup. I even heard them testing rs25 engines at stennis and visited a test stand when I lived in Mississippi in the 80s (not that that would teach me how it works)... A lot of this went over my head. I'll have to watch it a few more times to fully understand it all. Thank you for all this work!

[@Carstuff111]

And this is the kind of stuff I miss on TV, where you actually LEARN something. Thank you folks for posting stuff like this.

[@MikesTropicalTech]

Hey Tim, giving you a thumbs-up even before I start watching. We missed you but I know the tremendous amout of effort it takes to research and produce these videos. I promise I will only watch at 1x speed because of your rare high-information-density!

[@paullastnamehere3295]

This is an incredible explanation of starting a rocket engine. As a former jet engine mechanic, I am able to follow this a little bit. My mind keeps going back to the operation of a jet engine and the similarities of the two at the same time knowing that a rocket engine is a different beast.

[@PaddyPatrone]

Amazing Video, learned a Ton!

[@Pooneil1984]

Great video. Your explanations are right on target for an audience motivated to learn.

[@wiggancreativestudios]

I have been waiting for this video for a looooooooooooong time! Absolutely wonderful graphics! Thanks Caspar!!!!

[@aksh_x_]

Thank you for this amazing deep dive Tim! You're the best!

[@evanrichard2562]

Hey Tim, awesome video! For the RS-25 start sequence, at 50:25 CCV sits on the bypass leg, so as it ramps down and closes, it forces more hydrogen down the feedlines and through the nozzle coolant tubes

[@headp3]

That over pressure start up that blew out the pumps and the side of the chamber was insane looking. Very similar to a volcanic release.

[@Big.Ron1]

Thank you Tim and crew. This is amazing. I agree a video deep diving throttling and shut down would be great. This all blows my mind. Because of my age and remembering Gemini and all of Apollo the F1 is my favorite. And to think they did it all with slide rules and trial and error. This is crazy! Thank you again. Be safe.

[@matthanrath497]

Yes I remember using slide rules in the 60’s and we were not aloud to use scientific calculator in the 1970’s from Texas Instruments I thought the teacher was insane to not innovate stuck in caves they were cracking pointers and yard sticks across our butts for arguing this better way such 💩 heads they were

[@rajagopalg290]

Great Video as always. I was waiting for this video from a long time. Great Job team!!

[@MarketMaker23]

I wish there were something like this for all aspects of engineering. The Knowledge that Tim brings to rocket science is astronomical and I can’t get enough of it. Thank you, Sir for your time and expertise in teaching use just a little of rocket science

[@jeremyglass4283]

Great job as always Tim! This video is one of the most knowledge-packed pieces of content I've ever seen, and quite frankly blows even your other deep dives out of the water. I couldn't have said it better: it really does give you an appreciation for all the hard work that goes Ito engine development. I think anyone who regularly complains about how long it is taking to develop an engine really should use this as a reminder of just how ridiculously difficult solving every single minute problem during startup really is. This one was truly worth the wait.

[@Smannellites]

Excellent video, very clear and very well presented. Thank you.

[@JerkerMontelius]

This is like reliving the highs of the Apollo program or the first shuttle launches. Great job!

[@cesar5887]

Amazing video, just great as always. It's so cool to see how you've really become a reference in what I would call space journalism. You now have all these incredible deep interviews with these companies' CEO explaining their work, and you perfectly use them in this video to explain different topics. Great work

[@timpadgett8679]

This was exceptional Tim, thank you. I’ve been interested in these topics since I was a 6 year old boy (that adds up to a big number now) and you answered SO many questions with this it was hard to keep up with all of them. I hope you become convinced that you're the best at this. Andy freakin' Lapsa thinks so. Good enough for me.

[@EverydayAstronaut]

Thank you so much!

[@sdebeaubien]

Thanks so much Tim! Again, you've created a college level overview and put it out there for the general public, at no real cost to us. Amazing, simply amazing. I've only viewed up to the "Starting a Rocket Engine in Space" segment so far, but the explanations along with diagrams and video are all adequate for the non-rocket scientists like me to "Get it", or at least, get most of it. Thanks to your team as well for putting everything together! Elon sure should offer you a job! I think back on those videos where you and he were having discussions, and you both were doing "Real time" design on the fly, that was so cool!

[@favesongslist]

Yet this is still just an overview, imaging the maths and material flow science to make even a single valve work at these temperatures and pressures to operate reliably with this sort of precision and variable flow rates. No wonder it is said rocket science is hard.

[@racingflying4803]

Tim, how in the world you managed to the the pressure, speed, temperature graphs on the engine? Magnificent! This video is gold!

[@planemo191]

Jaw dropping. I've watched this 3 times and it's still complicated. I'm going to keep watching until it sinks in properly, thankfully easily done when it's so amazingly well presented! Thank you!

[@jamessimon3433]

Great as always Tim! Im curious, does gimbaling the engine add a great deal of complexity to the engine? Does pointing all that thrust cause great shear stresses to the system?

[@Horus2Osiris]

So proud of you! Thanks for keeping astronautical everyday comprehensible! Update; mind-boggling details reveal the pure genius of SpaceX... and those other guys...

[@SpenceMan01]

I’ve always had a fascination with and hefty appreciation for all that goes into spaceflight. This video (and the other two prerequisite videos) have boosted that appreciation to an all new level. The nexus of so many disciplines - chemistry, physics, engineering… it’s mind blowing and my respect for the brilliant folks that do this is off the chart. Thanks for giving us a great explanation and peek into the deeper levels behind these engines!

[@QuantumHistorian]

Simply brilliant. I have to stay I'm not a fan of regular Everyday Astronaut content (nothing wrong with it, just too much bubbly excitement for my tastes), but these longer in-depth lectures / documentaries are truly excellent. It's not afraid of going into technical details, but it also doesn't lose the trees for the forrest. And, to top it all off, it's (as far as I can tell) entirely correct with only the most minor inaccuracies in using technical term.

[@bwjclego]

This is your best video yet. You really set up a strong base with the previous engine videos and the factory tours, and this took all the prior knowledge to a whole new level. Little details like torch igniters, valves and bypasses, purges, and how the engine modulates valves to deal with transients were so informative and almost all new information to me, even though I'd say I have a pretty good armchair knowledge of rocketry. Fantastic work.

[@jimmykreutz6087]

WOW I've literally watched every episode that Tim has referred to as examples, what a dream this guy is living everyday, great job TIM, it's no wonder you don't work at spaceX and NASA at the same time..I myself and my 6 year old son feel like rocket scientist from watching so much of Tim's content..my son AXEL would like to congratulate you on your success and expansive knowledge, maybe some day we could have the honor of watching a launch along side you his hero.. great work 😁

[@goldengoat1737]

I know you have a lot going on being an astronaut and all. thanks a lot for putting some of this super detailed rocket info that we all love!

[@eamonia]

This is my second time watching this and man, I forgot how much fun this is to watch. I will most likely retain very little of this information but going through all these extraordinarily complicated processes is a really engaging and fun way to spend my time. Your brain is a muscle and if you're gonna use it, you might as well have some fun in the process. Thanks Tim.

[@charlesrovira5707]

Wow, you lay down a *_LOT_* of information on a complex subject and you don't _skimp..._ I have *_loved__ it every time you have done a _deep dive_ because they're wonderfully informative. Your interviews with *Elon* were *_epic_* too. Thank you!

[@danielbrowniel]

I love this stuff. I feel like Tim has covered so much on rockets he's going to have to move to another space exploration subject soon. What else is there?

[@macjonte]

Striling powered submarines? ;) They say submarines are the second most complicated technical vehicles you can build… :)

[@peterfireflylund]

Guidance and control, aerodynamics.

[@dxradio33]

Holy Cow! Who knew? Fantastic primer Tim. Really thought provoking , especially because we take it all for granted. They light up and they shut down. For most people it is that simple and not worth further analysis. Outstanding and thanks!

[@JS-og6lh]

Fantastic, educational video! Very well-done. I learned A LOT! You and your team are doing a great job!

[@f205v]

Tim, this was the most fascinating and information rich hour I ever had in my life. Will have to re-watch it at least a couple of times.

[@ragaloft]

We owe such an enormous debt to you and your team. Thanks as always, Tim. 🤓❤️

[@colinwinterman]

In just one hour Ive just had the best education ever on rockets, bless you mate.

[@PikaPilot]

Well, ignition tests just became a lot more interesting. Thanks for the video. I wish I had known about all this earlier in the Raptor testing campaign

[@janedoe9940]

Is it just me or the Ignition part is totally awesome?! Also, the example section - Tim, you're amazing! Hats down for making this part, it's really good. Respect!

[@OzAndyify]

Excellent stuff Tim. Some of the best education I've watched in ages.

[@reddmst]

As someone put it: "there are a thousand different things that can happen during a rocket engine start-up, but only one of them is the right one". Great video!

[@SmogandBlack]

I was really curious about this aspect of spaceflight, so thank you very much for such insight: you are doing a fantastic job and your voice and your face are so friendly and smiling (and enthusiast...) that it's a real pleasure to watch your videos. This one, in particular, was top notch (insanely good, as you would probably say 😊...).

[@juanixinauj]

Woah, Tim! This video has tons of info crammed into it, but it's still pretty digestible! It's great! That's really a feat on itself, considering the subject at hand. And it clearly puts into perspective all of the amazing stuff is going on when you turn the key and get your rocket engines revving! =P

[@syntheticmonk]

Your content is so high quality and so worth having online for people's learning pleasure. And I can tell that the propellant for your ambition is the best fuel type of all: Passion. May I dare say, sir, you've found your ikigai.

[@daStitches]

Awesome video! Thank you for all of your content, especially these educational videos!

[@NotRexButCaesar]

I am glad to see another explanatory video. These are the heart of the channel to me.

[@RawandCookedVegan]

Amazing quality Tim, thank you.