NASA's clever technique to make combustion chambers

[@BreakingTaps]

I am honestly stunned how quickly those extra combustion chambers sold out! 🤯 I assumed they would dribble out over a few months, instead of a few days! If you still want one, I'm going to make another small batch. There's a "notify me when in stock" button on Etsy if you're interested. Thanks to everyone that purchased the first batch, hope you like them!

[@kyohiromitsu4010]

3d printing has very low strength.

[@Eduardo_Espinoza]

I was thinking of doing something like this, awesome how it turned out! :)

[@1islam1]

@@kyohiromitsu4010 🔴 What Is Islam? 🔴 Islam is not just another religion. 🔵 It is the same message preached by Moses, Jesus and Abraham. 🔴 Islam literally means ‘submission to God’ and it teaches us to have a direct relationship with God. 🔵 It reminds us that since God created us, no one should be worshipped except God alone. 🔴 It also teaches that God is nothing like a human being or like anything that we can imagine. 🌍 The concept of God is summarized in the Quran as: 📖 { “Say, He is God, the One. God, the Absolute. He does not give birth, nor was He born, and there is nothing like Him.”} (Quran 112:1-4) 📚 🔴 Becoming a Muslim is not turning your back to Jesus. 🔵 Rather it’s going back to the original teachings of Jesus and obeying him. More ....

[@kyohiromitsu4010]

@@1islam1 lol

[@CountryDick]

Did shit.

[@JKTCGMV13]

I worked at Rocketdyne (builders of the RS-25, RL-10, F1, etc.) for 3 years. I did software though, so I can’t comment on the manufacturing process other than to say they have MASSIVE lathes.

[@BreakingTaps]

Oh man, yeah I bet the manufacturing facility is wild! Would love to tour it some day!

[@Splarkszter]

@@BreakingTaps +1 i would love to see that too.

[@Xsiondu]

Me +3

[@JKTCGMV13]

They did occasional tours of the campus (they have some engines on display) but I don’t know if those tours went through the manufacturing area. They might’ve? They have parts on display in there too. Not sure what it takes to get on a tour like that

[@thatyoutubeguy7583]

Why can’t you comment? Is it a national security issue

[@papparocket]

Great job! It does look a lot like the chambers NASA and the industry made. While the Narloy Z is much stronger than pure copper, it isn't strong enough by itself to withstand the very high chamber pressures. Beside the hydrogen embrittlement, the nickel closeout (usually including a small percentage of copper, aluminum and titanium such as in the K500 nickel alloy that resulted in precipitation hardening) was as thick as it was because it is what provides the structural strength. One additional thing we added in the late 1980s when trying to qualify engines of this type for use in expander cycles rocket engines to be used in upper stage rocket was *very* thin "V" shaped slots opening to the inside of the chamber that went about halfway up the lands (wall between coolant channels). This is because the hydrogen *inside* those channels are at a far higher pressure than the combustion gases inside the chamber. In our engine the chamber pressure was 3000 psi while the discharge pressure of the hydrogen turbopump was about 6000 psia. When the engine is running, the thermal expansion and high pressure loads cause the copper in the lands to undergo plastic deformation (which means that it won't fully spring back to its original shape). As a result when the engine is turned off and cools cracks often form in the lands and those cracks are usually at the point of highest stress, which is the corners of the channels. The engine I worked on was targeted to replace our workhorse engine the Pratt & Whitney RL-10. Upper stage engines have to start not once, but at least twice during a mission. Their first burn is during the last phase of the initial launch to complete insertion of the upper stage into low earth orbit. At that point the engine is shutdown and completely cools off. Then at some point up to several hours later the engine has to be reignited to send the upper stage into a transfer orbit to a higher orbit (such as sending a communications satellite to geostationary orbit). The start sequence of an engine involves a chill down where hydrogen is slowly flowed through the engine to reduce temperature to -427 F (temp of LH2). This is need for many reasons too many to bore you with here. But an undesirable effect is that the lands shrink way down. They are designed to do that when there are no cracks. But if cracks formed because the lands were crushed during the first burn, the chill down will cause those cracks to expand greatly because the copper loses a lot of its ductility at those very low temperatures and so is much more prone to cracking, especially if there is already a small crack to serve as a starting point. As the engine pressure and temperature rise during the second burn, the cracks in the copper can cause the wall between the coolant channel and the chamber to fail and the hydrogen will flow through into the chamber at that point. The amount of propellant lost from the failure of a single channel isn't huge, but the main effect is that the portion of the channel downstream of where the fracture was is now no longer being cooled and quickly melts through. Also the lands between channels need hydrogen on both sides of them to keep them from becoming too hot. With no hydrogen flowing in a chamber because it leaked out upstream first the wall between the channel and the chamber melts. Then with combustion gases on the lands between the channels on each side, the temperature of the land gets too high and also fails. Now there are three channels that have failed. Quickly the zipper effect results in a total failure of the engine. The V shaped slots serve as a way to reduce the stress in the lands. As the engine heats up and pressures rise the copper in the lands begin to expand and the V slots in the lands close. But because the portion of the expansion where the V was closing didn't result in any stress, the final stress level is much lower than it would be without the V and the copper never reaches a level where it undergoes plastic deformation. As a result when the engine is shut down the first time, the copper in the lands returns to its previous shape without cracks forming and the V slots open back up. Then without the cracks when the engine is restarted there is a *much* reduced chance the walls of the hydrogen cooling channels will fracture and the second burn goes as anticipated.

[@BreakingTaps]

This is really fascinating, thanks for sharing all the extra details! I had read about the "doghouse effect" making the channels themselves thin over time and eventually rupture, but hadn't read about the space in between the channels experiencing issues. That's really interesting! And seems like a really elegant/simple solution to what was probably a really complicated problem to analyze. Super neat, thanks for sharing! ♥

[@ibbylancaster8981]

Dude, my dad would have loved your channel. He was a machinist, woodworker,etc. He worked for 35 years at NC State University College of Architectural/Product Design in the shop that the students went to , turning drawings into reality. It was wood, metal and plastic capable (Back in the late 70’s) and grew with time and technology. Unfortunately he passed away last year, but the numbers of lives he touched over the years are vast. A lot of “tools” left with him. Much love from North Carolina. Glad that I found your channel.

[@carl2591]

GO PACK!! fun to see someone from a local, to us, college.. I bet my BIL know him, maybe.. engineering student in the 80's.. sorry for your loss.. sounds like he was one of the greats..

[@ibbylancaster8981]

@@carl2591 thanks. Dad worked at School of product and Architectural Design. He probably knew some of the same folks. Much love from Raeford 🤙🤙and definitely Go Pack! Aaaaahhhhhhoooooooooo!

[@shaunhall960]

I was a kid back in the 70's and our next door neighbor was a rocket scientist for the Apollo 14. I remember her talking about how they built the rocket. She is the one that really got me into astronomy. Love you Sue!

[@KnowL-oo5po]

you will be alive to see 1 million people in mars

[@jonnyj.]

Its so mindblowing how the rs-25, an engine designed in the early 70's, is considered probably the 2nd most advanced and efficient rocket engine ever flown to this day. More insane is that the design has literally not changed, from the metallurgy of the turbopumps to the tolerances and manufacturing techniques. The ones on the sls are the same ones that were flown on the space shuttle.

[@andrewdoesyt7787]

It’s even more mind blowing the that #1 most efficient rocket engine, the rl-10, is even older?

[@Wolfiecolada]

"more advanced" doesn't always mean "better". fewer moving parts and simpler designs often are more efficient and reliable. just ask munro.

[@ahfreebird]

@@Wolfiecolada I did. He just started ranting about MBAs being useless???

[@avroarchitect1793]

@@Wolfiecolada yup, this is why SpaceX is blowing up so many prototype engines trying to perfect the Raptor family of engines. Despite going for the most difficult combustion cycle type it is simpler in parts while being more efficient.

[@huntercooke9592]

They built the V1 rocket in 1944 and where the Rs-25 got its fundamentals

[@EverydayAstronaut]

Woah! Awesome to see our website and thanks for the shout out!!! Great video, love this!!!

[@BreakingTaps]

Thanks Tim! Huge fan of your work, really great educational videos!

[@TecSanento]

May be this tells you why recreating the rs-25 engines for the sls is this expansive. It looks like a process that's slow and hand work, with lots of possible problems - causing imperfect parts blowing up the bill

[@infinitetradecraft1837]

Based on my research into NARloy-Z a few years ago, the silver raised the thermal conductivity and inhibited oxygen mobility in the copper, while the zirconium aided in forming a refractory oxide layer, much like aluminum and titanium, which resisted the highly oxidizing environment of the combustion chamber. It was the same alloy used in the linear aerospike planned for replacing the F1 engine, and that engine used aluminum backing structures to provide mechanical strength, while the copper formed the chamber walls. As a hoop structure, the need for additional bracing was minimized in the SSME.

[@doyleself6849]

Hey you win that's over my head thanks.

[@pucmahone3893]

Ahhhh….yea…..I believe you know what you are saying….. Way over my head!

[@tysonristau4995]

Aerospikes are cool

[@malibudan]

More detail please?

[@allakin8574]

I was an electroplating process engineer at Rocketdyne from 1975 - 1980 and worked on the RS-25 (known as SSME in my day). Much of your description is spot on, but we had buckets of Secret Sauce (tips, tricks, techniques, process controls) that took 6-8 years to develop in the engineering lab and then transition to a production environment. I can’t tell if the art has been lost, or you omitted for brevity.

[@born-in-Atlanta]

I LOVE your “secret sauce” reference.

[@wheelsandwings28]

ok now reveal it

[@acarrillo8277]

@@wheelsandwings28 He can't, ITAR

[@TrainWorxStudio]

The art has not been lost. Look out for the ITER beam source grids 👌

[@StarGateSG7]

These days using electroplating is a tad old-fashioned when you can thick-film sputter in a vacuum chamber Aluminum Oxide ceramics (i.e. Corundums aka Sapphire-like) coatings and then Tungsten coatings which can withstand 3,422°C (6,191.6°F) ....AND... if you want to go more exotic, use thick-film sputtered Hafnium Carbide to get 4000°C (7232°F) worth of thermal protection onto your 6061-series or 7075-series Aluminum CNC-machined and cyrogenically surface hardened combustion chambers and nozzles! AND nowadays I can also design and machine via CAD/CAM/FEA an entire hemispherical combustion chamber into three parts and have the cooling channel grooves CNC-machined as half-circles on the outer and inner surfaces and then fully-align when bolted together. You can even use 6061 series aluminum or 7075 series Aluminum and just coat with a Corundum and then a Tungsten or Hafnium Carbide layer for maximum thermal protection. Much cheaper and easier than using these Copper/Silver alloys! V

[@6alecapristrudel]

Since you seem like a fan of plating, I'd like to share my recipe for making parts conductive without graphite. It's an alternate acid version of the silver mirror Tollens test thing. Sometimes things you want to plate get destroyed by base. Say PLA which gets eaten by base and basic silver baths don't stick. So what do you do? Make evil silver lemonade. Ironically metal doesn't play well with it unless it's already silver but it is what it is. I keep 4 stock solutions: A)10mg/mL AgNO3 B)100mg/mL Citric acid C)10mg/mL Na2EDTA D)10mg/ml Ascorbic acid - vitamin C Get 1 part of A, B and C and mix together. Then add 2 parts of D to start plating. To activate stuff for plating make some SnCl2 in HCl (to keep it from hydrolyzing). I add whatever amount of my 100mg/mL SnCl2 stock to enough water to soak the part. After the tin soln. rinse off lightly with distilled water and soak in dilute AgNO3. 1 or 2 ml of soln. A in whatever water to soak it again. This seeds silver nanoparticles on whatever your substrate is. Sometimes you can see clear objects get a slight brown tint. The plating solution is truly electroless for a few minutes and only plates activated stuff but then starts plating more and more and crashes out silver powder. Rinse out the parts after activation and before plating to remove loose Ag NPs and extend the time before it crashes out. I've had items completely silvered while the solution was perfectly clear and the container wasn't plated at all. Still plenty good enough for seed layers without base, ammonia or formaldehyde. ..

[@iBlue0riginal]

I'll totally steal this.

[@BreakingTaps]

Cheers for the tip! This is going straight into my notes on plating for future use ♥

[@integza]

This is a really cool method ! Thank you for sharing!

[@coyotedomino]

thought it was gonna be a simpler lost wax casting, but lost wax electroplating-! that’s a really cool technique. excited to see you on N☆!

[@PsRohrbaugh]

I've never had anything against 3d printing, but this video does an amazing job of showing how much you can fabricate with older techniques and a little cleverness.

[@hobbified]

Sure, 3D printing doesn't make anything *new*. It just makes some things *cheaper*.

[@M_Northstar]

...And a LOT of patience: 1 cm of nickel plating at 20 microns an hour would take 500 hours, nearly 3 weeks, nonstop.

[@PsRohrbaugh]

I 100% agree with both replies! I just feel traditional machinists don't get enough credit by the "wow 3d printing" crowd who often seem like they believe 20 years ago all we had were hammers and chisels. With a bit of clever thinking, plus technologies like EDM or electroplating, you could fabricate quite complex parts. Sure there are advantages to drawing something in CAD and clicking "print", but it's kinda like desktop publishing in the 90s - it had an impact on what the common person could do much more than the professional.

[@bumpstart21]

@@PsRohrbaugh Right. Years ago I was the cnc nerd kid who worked with some real old school tool makers. They would show me some interesting techniques like crush grinding for complex form grinding. Maybe just to remind me what up :)

[@wktodd]

Interesting technique. You may get better plating results if you have motion between the part and the electrode , to even out the field strength. A commercialL brightening agent would also help

[@kilomike5792]

That would help, but he would still get the dendritic growth. He needs a pulse plating power supply to really improve the quality.

[@BariumCobaltNitrog3n]

@@kilomike5792 And maybe a bigger part. Soo tiny...

[@keatoncampbell820]

As a welder I want to recreate the brazed channel nozzle to make an engine. I believe they used torch brazing, which makes my head hurt. I want to create a small motor with tig brazing. If you want I can make a nozzle to whatever specs you want, I have a small lathe I could use to bring it into tolerance. Would be useful for you for testing!

[@infinitetradecraft1837]

We were working with some students a few years ago on a regenerative cooled small scale engine, and had some reasonable luck with furnace brazing, but I think either way there's always *some* torch work. Tig brazing could definitely add some automation to the process, but the stacks of tubes are so pretty it almost begs to be hand made.

[@keatoncampbell820]

@@infinitetradecraft1837 I agree! Tig brazing would be easier for hand brazing only on a smaller nozzle, there's some necessary amount of heat bleed around the working area required to prevent distortion later when heating and cooling. It's really hard to compete with hydrocarbon combustion in terms of generating heat but tig is still very nice bc the precision it can offer is ridiculous!

[@ovanai6277]

@@keatoncampbell820 Are you sure your combustion chamber can export to USA or some other countries? I think it's quite difficult to export for some kind of combustion chamber which is about 4 to 5 times bigger than the one mentioned in the video.

[@ovanai6277]

@@keatoncampbell820 I hope you can finish well with your combustion chamber. Wish you always success in your work.

[@keatoncampbell820]

@@ovanai6277 i live in the United snakes myself so shipping around is less of an issue. Truly the biggest issue with shipping big metal hunks is the cost of freight due to specialized equipment, and I am poor

[@mikedrop4421]

The way they built the huge bells for the F16 was amazing. They built the largest brazing kilns in the world to fuse the cooling tubes together and when that NASA executive said we can't go to the moon anymore that was part of what they were talking about. They don't have the equipment or people capable of that kind of braising anymore.

[@BreakingTaps]

Straight up nuts. It still astounds me they were able to build those giant engines at the time. Had to quite literally build all the infrastructure to even manufacture the things. On the note of lost-tech, the original company that did the Narloy-Z castings dismantled the equipment for it after making the shuttle blanks. And it was a proprietary process, so NASA has more recent papers talking about replacements for the alloy and manufacturing it since they can't just re-use the same as before 😢

[@dennisthompson6242]

I worked on these engines at the Rocket Engine Test Facility at NASA Lewis in the 1970s. We were the main facility for producing and testing this type of combustion chamber. I remember quite well the Z alloy and the nickle plating operations. Our chambers had about a 1 inch diameter throat and weighed maybe 50 lbs. They were in the 5,000 to 10,00 lbs thrust range. They each took weeks of electroplating. We tested each one to failure and and had quite a rogues gallery of burnt through engines. I have tried to explain the process to people several times over the years so this video will really help. I was often the engine operator, stationed only about 50 feet from the test stand. The room was very heavy reinforced concrete with a thick steel outer shell. We viewed the test stand through a steel periscope that had 40 panes of bullet proof glass at the end! My hand hovered over the abort button but the scientists hated to abort until the engine was destroyed. If a LOX line ruptured it spewed huge flames as the 3000 psi LOX burned the heavy wall 2" stainless steel pipes like a Roman candle. here is an overview of the RETF: www1.grc.nasa.gov/historic-facilities/rocket-engine-test-facility/origins-of-the-retf/ Here is the gang I worked with. The man on the far left with the Dutch boy haircut is George Repas, one of the main inventors of this process: www1.grc.nasa.gov/historic-facilities/rocket-engine-test-facility/retf-staff/

[@rdallas81]

Very cool

[@bartekburmistrz8679]

Thank you for this video, I always thought that to make internal cooling channels are impossible to make DIY, but now I see that it have been my mindset that's been wrong, there is always a way

[@thomaslindell5448]

I absolutely love the voices in the old instruction videos

[@CaskStrength777]

I had wondered so much how you did this considering wax is not conductive. Makes total sense, fascinating

[@AsymptoteInverse]

Everything about any working rocket engine is remarkable, but there are so many extra-remarkable things here. I'm particularly impressed by the stones on whoever said "You know what? Let's just electroplate a centimeter of nickel onto the thing. That'll do it." I'm also super-impressed that you managed to replicate this at all, let alone on such an adorable scale. Cheers!

[@wildgophers91]

You know I don't typically enjoy the "WATCH ME BREATHLESSLY EXPLAIN SCIENCE" videos, but I'm really enjoying your presentation style in this one. (maybe because it's not so breathless)

[@wildgophers91]

Also you're actually, like ... doing work in this which is great.

[@BreakingTaps]

Thanks! And yeah, I like to actually make/build/fabricate stuff in addition to talking about. Feels more relatable to actually point at a physical artifact rather than just vaguely wave at some CGI or greenscreen animation :)

[@jeffmcdonald101]

@@BreakingTaps You do a fine job of both sir.

[@carrickrichards2457]

I played with electroplating, lost wax and sand mold casting when 11-12 years old using lead bullets in the sitting room fireplace (Brave parents!) Wish I'd had you channel then. Thanks for sharing this

[@quirkyMakes]

I love the fact that we basically use the same technology as 50 years ago just more refined and robust. I still think it's the best way although being able to 3d print some parts is really helpful and speeds up manufacturing

[@bullywa]

there are some problem - rocket nozzle needs tight connection with copper heatsink(metal 3d printing like slm or sls only one material) , any void will cause burnout. It could be done with special techniques of forming.

[@quentin1362]

@@bullywa Fortunately new technologies arrive. It's now possible to print multi-material parts by FAST/SPS or LPBF, maybe not such big parts but in few years for sure.

[@corujario2752]

Seeing someone taking such a project with the level of detail you did is encouraging and impressive. Congratulations.

[@badherodot]

Very cool to see this technique used in manufacturing like that. It reminds me a lot of the lost-wax casting method that’s been used in bronze sculpture for thousands of years. Thank you for sharing!

[@eicdesigner]

Yet again I stumble across a subject I never even thought about but watched the entire video with rapt attention. Thanks for sharing and know that none of us blames you for trying to avoid the algorithms. Good luck on Nebula!

[@dienelt5661]

This is amazing, exploring specific ways to manufacture complex parts is fascinating. This could be a video series if you have more material for it (although I imagine these would be really long and expensive to make). Still one of my favorite channel to this day, thanks for the top tier content :)

[@BreakingTaps]

I've definitely been thinking about something similar! Would probably need to pick an item that's a bit simpler just so it's more tractable, but it would be really neat to replicate a scale model of and explain the various ways it was done. Aerospace, rockets, etc is probably ideal since a lot of the information is public domain too. Will think it over!

[@josephpk4878]

Human ingenuity is remarkable. This was a great presentation - going to try out that STL on some metallic filament.

[@Bob4golf1]

Very cool! I'm impressed that you hung in there long enough to get a couple of working pieces. One of the more interesting videos on KZbin! Well Done!

[@MachiningandMicrowaves]

Fascinating as always. I feel encouraged to get my electroformed corrugated antenna horn project finished now!

[@solowri5100]

Hmmmm... I have no idea what the heck your talking about or what it means... but I'm intrigued. All I know is 1) I'm bored, 2) I think "corrugated" means wavy 3) I have no equipment and don't know how but I want to electroplate stuff too 4) I'm willing to learn stuff & things & whatnot 5) I like machines and have been known to use one or two on occasion 6) I use microwaves to help make my food taste terrible 7) My questions number just over the "many" designation but that's ok because I can make more 8) I am on occasion a Nigerian prince and would like to add your money to my money so we can both be richly 9) Number eight is a joke. Not like, the actual number eight, (even though it is silly looking and has to get part time work as the infinity symbol) but el numero ocho of this list and last but not least #9: Since you have passed the interview process I am willing to learn anything you would like to teach about whatever the heck it is you were talking about in the comments as well as that forbidden, evil dark arts of the Microwaves.

[@MachiningandMicrowaves]

@@solowri5100 The corrugations in an antenna horn are internal grooves which create a high impedance surface. Huge fun

[@overvoltagestudio]

Your equipment is like, really REALLY impressive! I’ve never seen any personal KZbin channel with this calibre of machinery

[@BreakingTaps]

Thanks! To be fair, its main use is outside of youtube for jobshop/prototype manufacturing stuff. But it does make for a great toy to use for videos!

[@dav1dsm1th]

It would have added another process - but it would be interesting if, after machining off the high spots, you could have applied a resist to the newly machined surfaces - so that the subsequent electro plating would target just the low spots. Not sure how a resist could be applied - but maybe from a negative of the shape that had just been machined. Just throwing random stupid ideas out there 🙂 Very interesting video, as always. Stay safe out there.

[@mndlessdrwer]

It's really fascinating how they managed to figure that out. I probably would have gone the route of just buffing on some finely powdered silver so I could leave the wax as machinable as possible, then just dip the whole thing in the wax until a coating the depth of the grooves had been deposited before scraping off the mounting flange, chucking it into the mill and machining the surfaces flush to eliminate excess wax. It is supposed to be a machinable wax, after all. Purging the majority of the wax out through heating is definitely a good idea, as it allows you to have a much larger surface area to dissolve the wax out chemically afterward.

[@lewismassie]

This was extremely interesting. Though I found the new technique also very interesting. I also happen to be one of they guys who knows far too much about the RS-25. So around STS-89 they started flying Block IIA engines with an entirely new combustion chamber design, I would imagine the new combustion chamber design was a part of that. Also I had no idea that it came from the J-2X either. Would love to read more about that.

[@BreakingTaps]

Grain of salt regarding the J-2X, I didn't find a specific citation for that but more pieced together chonology of the technique and when it was mentioned. So I might actually have that detail wrong (will pin an addendum comment if someone else knows more about it), or they both inherited the technique from elsewhere. But since J-2X was supposed to be the replacement before they decided to re-use the RS-25, it sorta makes sense they'd steal that bit of R&D and retroactively apply it I think. Interesting about Block IIA engines, I'll do some digging! Would indeed be interesting to see what changes they made to the combustion chamber. I think this plating process was a huge expense and bottleneck, so it would make sense if they were trying to streamline or even remove it back then.

[@Leadvest]

Years ago, I read gelatin thickened electrolysis solutions are used to improve plating evenness, but I never got around to testing it out myself. It's really unfortunate that plating with iron/steel are rarely discussed. There's an old adage that electro-winning iron is impossible. I did however find a patent on plating titanium, but even plating onto titanium is considered difficult, and don't get me started on aluminum, and beryllium.

[@BreakingTaps]

I actually made up an iron plating bath a year or two ago! But never really got around to using it and kinda forgot about it. Maybe I'll see if there is a technique/video I could make with it. I recall iron plating having an interesting history, where it was used super extensively and then basically stopped completely once alternate techniques/metals were more common. Could make a fun topic!

[@elguapo3436]

It was worth watching passionately, the process breakdown to the nitty-gritty details is really worth a ton of subscriptions, thank you for sharing. I understand why this has 1.2M+ views. Great content keep it up!

[@naota3k]

This is truly the best website. Videos like this being freely available is an incredible feat of the internet. I love it.

[@curedham2963]

This has to be one of the coolest videos on youtube, i wondered for a really long time how they did this but not questioned it thinking it was some sort of secret.

[@Bakamoichigei]

Brilliant stuff! 👍 At first I thought maybe you were going to talk about investment casting or something, but quickly realized that a cast part would be a godawful nightmare from a QC standpoint... There could be countless internal imperfections in the material which would be _so freakin' bad_ for a rocket engine's combustion chamber! This is my first time seeing this sort of process, and it's a real eye-opener. 🤔 One thing though; I noticed you were having a bit of trouble cutting back the wax to leave just the channels, much less doing so with a nice surface finish. Did you try using heated tools, or solvents? I know when my sister is working on wax masters for jewelry, she works a lot with hot tools for cleaner carving... And she also uses a solvent (denatured alcohol, I think.) to smooth tooling marks out of the surface.

[@BreakingTaps]

Ooh, yeah that would have worked better! I honestly just didn't think about using hot tools or solvents while scraping off the wax. I did heat the whole thing up a few times, helped re-flow the wax and re-stick it to the metal. But didn't think about using hot tools! Will keep that in mind next time I try something like this :)

[@gilbertcabasse6168]

@@BreakingTaps But couldn't you use a lathe with some coolant to remove the extra wax? I suppose it should remove tiny chips at a time, so limiting the stress on the wax that should remain, and so reducing the risk to stick it out?

[@user-fh2fm7vr4m]

Thank you for the nebula plug. I have always had an appeal for Nebula but never really saw an ad to show me what I was missing, but specifically saying hey this video is on Nebula is a great way I think.

[@ominguti6345]

Great video as always. I hope the diamond electroplating video makes it to youtube at some point. I paid for nebula just to see it. It is a bit disappointing there is no comment section on nebula. I would like to ask some questions about that video. For example, why choose carbide for the electroplating tool blank? Wouldn't nickel stick to steel much better making your tool last a lot longer? I'm guessing you choose carbide for rigidity, but the tool shape shown was a shape I think would work well in steel too. Perhaps you're planning future tools will have much larger stick out and be skinnier and this is just to figure out the process... Well. This video made me interested in the process. I didn't even realise it is doable in a hobby setting. Thank you.

[@BreakingTaps]

Perhaps some day! Especially if I can get pure ductile cutting working. (and cheers for joining Nebula, I hope you get some value out of the other creators too! I'll be trying to put stuff up there in the future as well, including like "director's cut" and longer explanations). Comments on Nebula videos is something of a hot topic internally, there's people for and against so not fully decided yet. Otherwise, there's a reddit for Nebula that a lot of folks use to ask questions about videos (www.reddit.com/r/Nebula). I've been keeping an eye on that. To your questions! You're correct, I picked carbide mainly for stiffness/rigidity. Truthfully hardened tool steel probably would have been fine, but I was concerned the small size of the tools (0.3-0.4mm) would lead to deflection issues. At that size even a little deflection can cause the tool to snap, particularly in a rigid material like glass. It was also something of an exercise in hard-milling carbide and using PCD tools. I've always wanted to but never had a good excuse, this seemed like a good one. 😁 Feels like I have a new tool in the toolbox now, being able to mill shapes in carbide for custom jobs.

[@sccolbert]

Well dang. It's a rare day that I come across a new-to-me manufacturing process. Thanks so much!

[@jbrownson]

Love seeing clips of your CNC. Would love a dedicated episode about it

[@BreakingTaps]

I'll see what I can do! Would love to talk about it more, just not entirely sure how to best show it other than "well here's the CNC!". Maybe during a shop tour or something!

[@jbrownson]

@@BreakingTaps I was in the market for a 5 axis machine for my garage and the MedCenter was very much on my short list, saw one in LA at a showroom. Wound up with a Datron C5 which isn’t quite as capable and not much cheaper, but less intimidating and fit better in my space. Starting to consider what the next machine is, Hermles are pretty impressive, but maybe MedCenter would still be worth looking at.

[@taterkaze9428]

This is fantastic YT. This kind of content can't be found elsewhere. Well done.

[@thom7440]

One slight correction... the rocket engines made from brazing tubes together didnt have a separate layer for the combustion chamber ... the brazed tubes were in direct contact with the flames .... they WERE the combustion chamber ... Other than that, really good video

[@HesTNTonPMS]

I am absolutely in love with the RS-25's No matter what! That Rocket motor under fire is so impressive to see, I can watch test firings of RS 25's without tiring

[@NastyNixels]

Zachary: This is my first time viewing your channel. Excellent content & well presented. Thanks for your efforts. TIP: If you ever need to do the wax onto copper: Spray the copper with shellac. This will give a thin coat that allows the wax to adhere to it. This was done in the renaissance for metal to leather bonding, so it’s been time-tested fairly well.

[@cosmicraysshotsintothelight]

He could also laser etch the slots to give them little micro pits for the wax to get a grip onto. Or even glass bead blast. I know it is a small scale replica though. Hey... build a bigger one. Make an actual rocket engine. Way more dangerous than those folks playing with SRB based toy rockets. About 3 times bigger than that one should do it. Seen that old man with the triple pulse motor go-cart? He's crazy!

[@etherealbolweevil6268]

Was walked around the making of jet turbine blades. 1 - cast/forge blank blade & inspect 2 - broach & machine foot & inspect 3 - spark erode straight cooling ducts along interior of length of blade & inspect 4 - heat and form the curves in the blade & inspect 5 - polish/finish & inspect 6 - inspect & inspect & inspect. Whole section of the factory dedicated to making and maintaining inspection equipment. Bent holes everywhere. Fantastic. Might be a bit tricky for the waisted tube, but certainly easier at small (and cost limited) size items.

[@bansci]

Amazing work, such a beautiful story from images, to explanation, to demonstration. Thank you.

[@jonlowrey]

I got the chance to help as a chamber wax/de-waxer and you are right about the manual labor involved. Plus always a chance not all the wax got baked out of the channels after plating causing FOD issues. 3D printing is awesome but not always (at least for now) cost effective. Great video and spot on. Can't wait for the next.

[@BreakingTaps]

Oh super cool! I bet that was so frustrating, after all the work for the wax to not get fully removed. And probably expensive too, ugh. 😢 And yeah, I even looked into what it would cost to 3D print these little models and it was wildly expensive. Can't imagine what it would cost for a full scale model, that also has to withstand all the rigors of a hot fire.

[@ianbottom7396]

Very cool (pun intended 😂) It wasn’t too long after I started 3D printing and designing that I realised the potential of learning to electroplate (at least at a hobby level) and so my journey down another rabbit hole began. Apart from the 3D prints I also use the process for organic items such as leaves, insects, rocks, wood etc, it’s such a cool process to see something become plated in metal right in front of you, possibly the closest thing I’ll ever do to Alchemy 😂 Anyway thanks for the video, I always enjoy your content

[@Xsiondu]

Do the insects have a favorite type of metalizing material? Can you give me adamanitium bones like wolverine?

[@skippityblippity8656]

@@Xsiondu Since insects have exoskeletons Unironically yes

[@GwynRosaire]

Placing gold inside a nuclear reactor to make lead was my alchemy moment.

[@ianbottom7396]

@@GwynRosaire very cool too but I’d be surprised if you did it at home. Is it true that while it is possible, it’s by far cheaper to buy gold?

[@cosmicraysshotsintothelight]

@@GwynRosaire It costs more than the natural occurring Lead. heheheheehehehe... You should have tried to make Mercury instead. ;-)

[@4dirt2racer0]

dude thank u so much for making this channel, i love your videos so much u cover the coolest stuff, i think the difference is ur genuine passion, it doesnt seem like u just make videos to get views n become a channel to make $$, u were probably going to do everything u did anyway whether youtube n the world or ur friends knew knew or nobody at all ever knew..

[@ehdeesign]

Another detail on tolerancing. The throat ID on the SSME is the most critical performance variable. A diameter variation of 0.0005" is a 1% thrust penalty. So considering the payload mass of the Shuttle, that is a significant loss of thrust. The engineers I worked with that designed the SSME said it generally considered a complete engineering masterpiece. The injector alone was incredibly complex. One of the guyd I worked with spent 7 years re-designing a SSME upgrade for AR, that got canceled, and never even tested. Not sure I could mentally survive that letdown of effort.

[@jerryanderson7466]

NARloy-Z has definitely gotta be one of the cooler alloy names out there

[@Carhill]

1:59 - That MCO joke XD

[@adeadelowo2110]

The ancient Chinese and the ancient Indians were also using the ancient lost wax method to cast even more complex pieces than a rocket combustion CHAMBER.

[@gastonnogues]

In the lost wax process you make the part out wax first, you then add gates and vents to the wax part…then you dip the part in a ceramic slurry and dust it with sand numerous times before firing it in a kiln to burn out the wax…then you finally get to pour the metal in through the gates, after it cools all the real work begins. I’ve done it. This is a different thing entirely. Not your daddies lost wax.

[@rdallas81]

​@gastonnogues sounds similar to sand castings for engine parts.

[@justinkane290]

6000 lb is not a pressure it's a force haha. Amazing process, and great video! Thanks!

[@ahmetunal8881]

I worked on one of these experimental nozzles about twenty years ago. We machined a mandrel from steel first, then they sprayed some special copper alloy on it, then we machined the channels on the copper nozzle. After that it went to another supplier, so I did not see the end product, but one of the mandrels we machined was about 20-25 inches in diameter, and about 45-50 inches tall, so it was a pretty big part...

[@TurbulentSphere]

Excellent video! Do you happen to have a link for the retro NASA "how engines work" clips you used?

[@BreakingTaps]

Thanks! I believe most of those clips were snagged from this video: archive.org/details/SaturnPropulsionSystems1965

[@TurbulentSphere]

@@BreakingTaps Thanks!

[@adamh1228]

ha, this is fantastic. I am a mechanical engineer, with a strong background in copper alloy casting. And have done a bit of stuff with centrifugal casting, as well as plating.

[@smash5967]

Still waiting for the static test fire

[@michaelovitch]

Try bead blasting with fine grain or glass dust to get a matt surface so the wax stick on better.

[@abicol6010]

Why is "the machines used by the Machinist are called machine tools" so funny 😂😂

[@BreakingTaps]

Haha right?! I saw that clip while skimming for something else and just couldn't stop laughing, had to include it 😂

[@JesseRoamsFree]

As a nebula subscriber I’m very happy to watch you there, Wendover is the best

[@samuelschuur7044]

What machine did you use to machine the base copper part? That final "turning" operation looked pretty cool. Overall a very cool project.

[@BreakingTaps]

Thanks! It's a Kitamura Medcenter 5ax

[@EricBrummer]

If you're talking about ~10:16 in, that's a endmill in a mill, with an extra axis (4th axis) doing rotation, so achieving similar to a lathe turned part. As to the specific machines he has, I think he's mentioned but I don't recall.

[@samuelschuur7044]

@@EricBrummer Yeah that's what I figured - just a neat operation - the axis looks like it's compensating for run out which is very cool.

[@nasonguy]

Yo those dolly shots of the papers and stuff are straight up beautiful!

[@BreakingTaps]

Yay thanks! Was unsure if those would be visually interesting or just boring. Appreciate the feedback!

[@SBA_poiko]

There's a great Video by Safran (the aerospace firm) about how they use wax to create the complicated turbine geometries. Highly recommend it.

[@BreakingTaps]

Ooh! I think I found it: kzbin.info/www/bejne/Z6Wwaml4bJyhZrc Queing up for a watch this afternoon, cheers for the tip! Looks really interesting

[@SBA_poiko]

@@BreakingTaps yep this is the one

[@oldmanspooky6641]

Just found this channel!!! I’m hooked.

[@RobertLBarnard]

Can nickel be plasma sprayed? I wonder if the bulk of the nickel could be added after the initial electroplating? Although I guess the heating up of the substrate could carbonize the wax, and that would be bad.

[@BreakingTaps]

Not sure to be honest! Destin mentioned on twitter that it has been flame sprayed in the past (twitter.com/smartereveryday/status/1644446860067717121) so perhaps? I'm not super familiar with either technique though so unsure what the limitations are.

[@cogoid]

"Launcher Space" makes their engines by spraying a strong outer jacket on a 3D printed copper structure. They have videos showing the process.

[@OrenTirosh]

An interesting fact about nickel and copper is that they have the same crystal structure and can substitute for each other in one crystal at any ratio. This makes them form a really strong bond - essentially as strong as one piece of metal.

[@Saleemsan]

I was forty years in manufacturing, and I loved solving manufacturing problems

[@ericlotze7724]

I thought it was going to be a sand/wax core like water cooled engines, this is WAY cooler. (Unintentional Pun lol)

[@paulmakinson1965]

Pressure is not in pounds, it is in a unit of force (Newtons in SI units, pound-force in US units) per unit of surface (square meter in SI units, or square inch in US units). One Newton per meter squared is a pascal (Pa). Bar is more practical and often used in rocket engineering: 1 bar = 100.000 Pa. Pressure in the combustion chamber of a SpaceX Raptor 2 can reach 330 bar. A scuba tank is usually at 200 bar. The problem in a combustion chamber is the combination of pressure with temperature and chemically reactive gases. It is lethal for any alloy.

[@marianaldenhoevel7240]

Fascinating to watch you reproduce this byzantine process. Thank you very much! Have you set a launch date? :-)

[@BreakingTaps]

Hehehe, think I have a few more components to work on first 😁

[@WilliamPayneNZ]

I think you are greatly underestimating the appeal of niche scientific content on youtube. I will check out nebula, never heard of it. But I must say as a regular consumer of scientific content I would love for their to just be one platform to watch everything on rather than lots of jumping around. Maybe oneday people will be able to choose how they host their content and viewers can just search for and watch it from one search engine. Oh and fantastic video!! I am really glad it showed up on my recommendations.

[@mattymerr701]

Least you didnt say the pressure was the equivelent to 6 million bald eagles flapping or something

[@fixed1t]

A similar process was used for Jet engine turbine blades to form the film cooling holes and channels which they use to pump in high pressure cold air to keep the titanium blades for vapourising, I had a project at Rolls Royce AeroEngines using the Wisdom Systems Concept Modeller Know Based Engineering System (AI CAD) to design the film cooling holes.

[@Hailfire08]

lbs or even lbs-force isn't a pressure though, do you mean psi?

[@BreakingTaps]

🙉 (it was probably PSI, snagged the number from some rocketdyne whitepaper)

[@Hailfire08]

​​@@BreakingTapsif you calculate the chamber pressure as thrust (~500k lb-force) divided by nozzle neck area (10in diameter) you get 6,400psi, so your number indeed seems to be psi

[@dcw56]

It's amazing to me that a man with his own shop and his own brain can do anything at all like what NASA was doing in the late 70s. That is not a put down. It is truly an amazing thing. Thanks for the vid!

[@AlphaPhoenixChannel]

This was awesome! I had no idea how this was done WITHOUT welding a million tubes together

[@lucaburkhardt2592]

Next time someone uses pounds as a measure of pressur, imma do something real bad

[@jcbsrl]

I just stumbled upon this video. Your explanation is so easy to follow. I don’t know much about engineering, but I could follow along very well and you made it interesting.

[@jimmahon3417]

Sorry I was too late to pick up one of the model MCCs - I was at Rocketdyne working SSME for 14 years. Knew Tony Akpati, the author of one of those papers, fairly well - a quiet, highly intelligent person whose visits to my manufacturing department I enjoyed. The shuttle MCC really was an amazing piece of manufacturing engineering, and we grew used to the scale of all of the SSME components - to the point where our first encounters with the prototype RS-68 chambers were a little jarring. They looked like hot tubs by comparison!

[@Anthony_Gutierrez]

When I was a machinist we made a lot of parts for SpaceX using wire and sinker EDM machines. Those things can cut shapes that you can't do on any other machine too

[@JesseRoamsFree]

Never seen your channel before and that 5-axis machine caught me off guard! Amazing replica man

[@gordonpettus7725]

Great video, explanation, etc. Have your tried and/or can you comment on a couple suggestions. Try any of the following: 1. Roll/thin some very thin copper plate to a little more than the thickness of gold leaf, tin the nozzle ribs, and solder the copper to the ribs. Flow the work along the ribs so the inside surface is smooth. 2. Wind the thinnest copper wire you can find around the nozzle ribs and solder them in place. This will, unfortunately, give a rippled interior surface. So, 3. Reshape the thin wire so it is "D" shaped and wind the wire about the nozzle ribs so the flat surface is attached to the ribs. After you have added the copper, electroplate as needed to get the desired material and thickness. If these don't work, I hope they will at least trigger your brain to find a better solution. 😁😁 Good luck and keep up the great work!

[@BPSspace]

Your work is so impressive dude - the results are pretty great here!

[@BreakingTaps]

🥰🥰🥰 Thanks Joe!

[@ghostmanscores1666]

Lost wax method is really neat the detail can be incredible. Look at how it works with jewelry.

[@ryanrising2237]

So, my school has half of one of those old brazed-tube combustion chamber/nozzle assemblies. I think it’s an LR89 specifically. While the tube construction does seem accurate, the inside of the combustion chamber doesn’t have a jacket between it and the tubing - the inside is formed by those very tubes themselves. This is also matched by what I’ve seen of the F-1. But that doesn’t invalidate the video at all, this was very cool to see done.

[@bentrueblood8144]

2nd week on the job as a new engineer, and I had to go to a test stand, climb on a step ladder set under a SSME, and stick my head up inside the combustion chamber to inspect it... Even more fun is the technology of furnace brazing all the nozzle/cc parts together, using staged brazing at different temperatures (sometimes as many as 9 steps for some experimental stuff).

[@moepow8160]

I think that was cool what you did. I don't think I would have stopped as I am a amateur Hight Power Rocket member and I've been launching model rockets all my life. I've seen a lot of miniaturized versions of real size machines, why not a rocket. We have some members who use bi-perpalants, one being a liquid. And the thrust chamber is mostly a one time use; you have to buy another one. Yours could be used over & over once perfected. Yes, it would be a lot of work, but the achievement would be unbelievable. I also fly RC jets. I saw a miniature jet that was correct in every way, the guy machined or fabricated every part, it was incredible & it flew. Great job either way.

[@JoseJimeniz]

I just saw the short of this. The short is well-done. It's lean; without an ounce of fat. Kudos. And the i wanted to see more - like a Savage Builds type thing. Nice video. Nice work. Thank you. No, seriously. Thank you.

[@nathanhastings8293]

In 2002, I built an ultrasound reciprocating hole saw that cut .003 thick quartz into .3y cool125 diameter blanks. it was pretty cool, I used a aluminum oxide slurry that embedded into the softer metal (rather than plating). This was R&D for the semi-conductor industry. I really like the piece on the cooling pathways.

[@makingtolearn]

Super cool video! What an interesting process. I did some hot isostatic pressing on cast Titanium parts around 30 years ago and now do it on Platinum castings for jewelry I make. In jewelry making we sometimes do co-casting where we add wax to a finished Platinum casting and then investment cast gold into the wax area. We typically have to add in a mechanical bond line as well.

[@seldoon_nemar]

For anyone looking to get a 101 crash course on rocket engines and such, I can't recommend Everyday Astronaut enough. Tim does videos that will end up in classrooms or museums some day, and he can break a subject down so even the most novice person will be able to grasp the concepts

[@LordFalconsword]

It's amazing the ways they came up with to build machines in the 60s. They even hand wove the computer memory on the Apollo guidance computers.

[@dylanscalfscalf9488]

Interesting video! You did a really good job taking a complicated process and explaining it in a way that is easy to understand!

[@eliolmstead6219]

Definitely should make more and sell them if you have the time and resources! Amazing desk decoration for an Aerospace Engineering student!

[@SergiyFakasProfile]

well... Traditional US manufacturing technique for combustion chamber is to braze small tubes (see F-1). Soviet traditional technology is to mill channels in the inner chamber shell and then braze external wall over it. No wax or 3D printing involved but result is the same or even better. And, BTW, RD-0120 - functional analogue of RS-25 - was made in this way.

[@MarzNet256]

That's pretty cool. Blood vessels in animals are organized in a similar way to allow heat exchange loss of heat between blood going from core to periphery and blood returning from periphery to core (which picks up the heat). It is a countercurrent heat exchange mechanism, reducing overall heat loss. The most brilliant thing is that once the fuel absorbs the heat it is burned, preventing components from overheating. I think the Concord used the same strategy of using fuel as a heat sink.