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The power of an educated individual, fully aware of what the heck his machine can do. You'd be shocked to find out just how little a lot of self proclaimed machinists (hired at that) know about their machines, what can be done on them, etc. Most of them are weekend to weekend workers.
@@mostlymotorizedyou really don't understand the very very tight tolerances that engines require. This would have been EXTREMELY difficult to machine.
I feel like watching Rob dahm is another level of content creation. His videos are so indepth, and I feel like I learn a lot about not only rotaries but also mechanics in general. I love this content, man.
the fact this dude made this engine back in 2008 is WILD - don't think many people realize how much of a feat that was. And on top of that how much he got right with minimal mistakes. Obviously as time goes by things get better technology advancements etc. This thing is going to be insane.
To add to this, when making it he said he was using 60-70 year old machining tools, so that means its all “by hand” and im guessing he did the draught work for it himself too, the guy is literally a master engineer in my books, and i’m just happy they’re sharing this knowledge with us
It's so cool getting a proper video showing the inner workings of this mythical motor and I'm super excited to see it go together and hopefully fire up soon enough. There are so many weird myths and claims about this thing, just yesterday I saw someone claim this exact engine had been dynoed at over 5000hp with turbos, which is funny because it has never had turbos mounted to it.
@@hadrian2505To be fair, the engine for that did actually exist and produced a fuckton of power, it's just the rest of the car that ended up being fake.
@@claybrinkman533because it’s not possible, having an engine produce 5000hp doesn’t mean you can put it in a car! There is so much more involved to do that.
Even if it's not perfect, this engine is legendary, can't wait to see it run, also taking everything learned from this engine and the 4 rotor, how about a fully inhouse build twin turbo 8 rotor 🤔
The fact that you aren't afraid to go into full detail in your videos at the expense of a little extra time is perfectly suited for the rotary community. Your videos have peeled back the veil on what many people (myself included) thought to be a complex/mysterious engine... only to reveal how simple and powerful they can be. You are the inspiration that will keep the rotary scene alive for years to come
2008? Damn, that engine was designed & make 15 years ago? It's genuinely impressive considering there were limitations on some knowledge & machine. I honestly want to see Rob Dahm make a 3-bank 3-rotor (3x1) version of this engine himself, a revision 2 of this 12 rotors engine but corrected everything that is wrong.
Yeah this thing was absolutely bleeding edge and incredibly expensive back in the day. Hell, even though the tech has matured in that time, it would probably still cost the same now.
@TURST67 that's not true. Computing power, sensors, tools, CAD programs have all become much more powerful. As well as flow simulation programs a regular pc can run.
This is absolutely fascinating, and I love that you're pointing out a whole lot of things that I wouldn't have thought about. Not too many people understand engines that well, let alone rotary engines, let alone custom-built 12-rotor rotary engines. Great video!
The only thing that confused me was when Rob was talking about the engine being out of time with the timing gears. Wouldn't he just machine the splines on the inside of the gear to be 3 degrees offset to the outer teeth to eliminate the issue? assuming all 3 sets of rotors are only connected by those gears? Just a thought. This thing is so fascinating I can't get enough of it, what a machine.
I think ol dude knew it needed some finicky little touches and you were the perfect finicky little dude to make it happen. No one else on earth would or could enjoy this engine as much as you are enjoying it right now, you definitely deserve to have it.
When I first saw the 12 rotor a while back, my wish was to see Rob get his hands on it. Holy shit I can't wait to see the learning journey building this and what he's gonna do with it.
should talk to your local industrial bearing supplier R.E the end bearings - there are angular contact ball bearings that can handle relatively high (for a ball type) axial loads, and are normally same overall dimensions as standard ball bearings, and (usually) have a higher ball count due to their construction
I can't believe the guy designed this with so few problems first go. Massive engine knowledge and creativity...Genious level stuff really. Clearly it's not going to run a long time as it is presently built but with some design adjustments it looks capable of being a solid functional block. The value of taking it apart, seeing his design and how it started failing is off the charts. In a marine application this engine has serious potential as well.
All of this tells is that you aren’t going to quit until all 12 are singing together and insane a Mazda box good luck hopefully in 3 years this beast be on the track.🤟🏼
Hey rob, love to see how far youve came. Youve inspired me to get my build going as well as start a youtube channel myself(have yet to start it but getting footage) thank you for being you man! Keep inspiring others.
I'm loving this, it's great to see your accrued knowledge coming into play here Rob, you've come so far since I began following you and it's really great to see how far you have come. You're like THE rotary guy now!
time each bank as a traditional 4 Rotor, then set one bank to 0 degrees, the next 30 degrees out form the first, and the third an additional 30 degrees. every rotor should fire independently and a combustion should occur every 10 degrees of crankshaft rotation. the sound would be absolutely legendary.
they dont fire 3 times per rotation of the e-shaft (crankshaft), they fire 3 times per rotation of the rotor. the rotor spins at a 3:1 ratio to the e-shaft, making one ignition event per rotor per rotation of the e-shaft.
I JUST CANT HELP but think that this is a problem A.I. was made for! I mean I know you want to do this with your (combined) big ol brain power(s) and good gawd good luck to you but also I would be thinking about whipping Ken Blocks ass with whatever you put that in. Hoonigan vs Time Machine? lol Talk about chomping at the bit!! I can't WAIT to see that thing scream and it will literally SCREAM when it fires. Oh yeah- twin turbo too- just sayin... God bless you brother. Best content on the net.
Just a quick comment on the teeth timing issue. The problem as you describe it only exists when the gears are identical and on a radial angle divisible by the tooth pitch this issue could already be solved by the gears position relative to each other but could equally still exist. I hope I explained that well enough! :-)
It could also be solved by rotating that left gear a few splines on the crankshaft, as the crankshaft is where timing is set, the gears are just relative to the crankshaft.
Yes I think I am thinking of the same thing. Do not worry about the teeth of the gear being 3 degrees off. Compensate for that offset by changing the clocking of the e-shaft to the gear to accomodate for that tooth to valley offset. TDC on the center should have the tooth down, at the same time the left gear that is in direct contact with the center should have it's TDC at a valley pointed down. So yea, change the clocking of the splines to the teeth of the gear.
The machining on this motor is so insane for back in 2008. People in 2023 still can't do this style of work. Amazing work man. Stoked to see the rob touches on it
I’ve never been a big rotary fan but you talking about the physics and the way this whole system interacts has got my engine/physics geek brain going for wanting more of this build this is going to be epic!
Its definitely mind blowing seeing this 1 of a kind piece of engineering. The old man who built this is a genius he gets an idea for a motor that he wants to put in a boat of all things and completely re-engineered a rotary engine. Then the 12 rotor rotary engine was born. Now thats how you follow through on an idea 😂😂
Been watching you for a while now and your recent content made it to the new heights. You are really number 1 youtuber on my list now. And the fact you have so much experience... Thank you Rob.
6:36 Otherwise called Positive Crankcase Vacuum ports, on any other engine. Typically has lines run to it with a PCV valve that regulates the direction the air flows and helps to prevent oil from going places it shouldn't (like the intake plenum or right behind the throttle body on most cars along with the EGR stuff.... )
Nah man, you're mixing stuff up with wet sump and dry sump engines. On wet sump engines you have a pcv system that creates a vacuum in the engine by attaching a hose from the intake plenum to the crank case (or valve train area, which has a direct connection to the crank case). On a dry sump engine you create that vacuum with the dry sump oil pump and you don't have a pcv system.
Hi rob just love your enthusiasm for rotary engines I love them and have learnt a lot from watching your videos thank you and keep them coming can’t wait to hear and see that 12 rotor running all the best from the UK
Good luck guys, hope your patience and dedication paies off in the end !!! First start first sound, fear off blowing somethin'!!! This is exiting !!! Good luck guys !!!
You need to flip one of the drive gears over to get all 3 banks timed perfectly. If each gear is off by 1.5 degrees, say clockwise, then flipping one gear over would make it 1.5 degrees off counterclockwise. A drivve gear mounted backwards would cancel out the timing offset.
To solve the 3* timing offset in the gearing, would it be beneficial to have another custom gear made with the inner spline for the shaft to account for the 3* offset? seems like you might be tinkering with that idea already from the marks you made on the inner spline circumference. anyways pls throw this 12 rotor in that boat of a Lincoln lol!
They may have already designed this in. If the key is not centrally aligned to a tooth (or valley), the gear may have 'a' and 'b' sides. Ie Flip over to change timing....
it might work to just rotate one of the gears to get to a point where 3* is offset. dit that to my mazda bg 323 with a BP 1.8l 16v engine when running a ex camshaft on the intake side and had to recount the timing of the camshaft as the gears got different timing marks.
Regarding the timing of the shafts. This could be changed with the position of a 'key' in the sproket, or even by rotating the cavity slightly in the block. If the key is not aligned centrally with a tooth (or valley) then see/check if the sprocket can be flipped over.
Rob is the saviour of all rotaries, can't imagine him doing all this several years ago but I'm happy Rob chooses this path, cause honestly no rotary shops are ever gonna give this level of details to their customers, let alone on RU-vid. Just keep doing you Rob and share what else you know on the engine, looking forward to the firing up on the 12 rotor!!! ❤
that's dope. I admire your informational retention and ability to break down the inner workings and mentally comprehend it, and analyze not only you're own understanding of it, but also where it could be improved upon based off the issues that have shown.
I'm wondering if those stationary gear bolts could be extended to thread into the center the side plates and keep them from bulging. Not sure if they would need to be blind holes or if through holes would work and not damage any of the side seals of the rotor.
I know that Piston engine guys normally do cold treatments on parts to prevent breaks warps and stuff like that im curious if Doing that to parts in there would help
19:21 a potential solution would be to either have bolts, bolting it down to the aluminium all the way around the inner lip, machined flat with the item installed and sunk from the face by a fraction of a mm. The rotor shouldn't care. OR an intermediate plate that sits on the inside of the aluminium, is bolted and has a machined thread that accepts a ring, which itself is threaded and meant to suck the plate in.
A 24 rotor powered boat would be incredible. Even if each rotor only managed 110hp the boat would make as much as 6 mercury 450Rs with probably 1/3 the weight.
The Eunos Cosmo was supposed to come with a V12 for the American market, however this 12 Rotor would be amazing inside a JC cosmo chasis, maybe a cool widebody too. The long hood/engine bay is perfect
It's cool to see mention of a Eunos car, the Cosmo was a pretty cool looking car and this would make it a crazy thing, while I don't have a Cosmo I do have an 800 with the Miller cycle engine, It's beautifully complicated in every way possible, shame it doesn't run properly, I eagerly await the day I figure out what's wrong with it.
You're right in that the first thing I thought when I heard about this engine was, "How do you remove all that heat?". And, since I want to see this thing powering a classic Chevy muscle car, I'm still asking that question.
If you can figure out all the challenges, my vote is to put in a old Rolls Royce like a silver shadow and drive around like an actual turn of the century supervillain. Love the content!
I just gotta say, this is the most excited I e ever been for a RU-vid project, not just for cars, but for pretty much anything, super stoked for how this behemoth performs after all the TLC is taken care of
Man I'd bet the guys at haltech are crazy enough to want to help with some bonkers custom solution to this. If I were an engineer there I would definitely be trying to get someone to let me work on some monster frankenstein ECU for this thing.
I don’t comment much but I couldn’t resist tonight. This will be an epic experience!!! I can’t wait to hear this fire and run!!!! Thank you for all your incredible videos. This is Gas Pump Rob also in Southern California - Rotary enthusiast and old gas and oil collector.
Rob, I know you have dial indicator. Not trying to tell you to do anything, but I would mount a mag-base. Then you can see how much spring you get back. Seriously brother. I cant wait to see this motor run. If there is anyone that can do this, it has to be you. Great job explaining everything. To be as 100% technically correct, and bring it to layman's terms. GOOD LUCK!!!
And Rob now has the knowledge to see and detect problems with rotary engines. Creating his 3-rotor and 4-rotor with all the CNC machining has taught him sooo many things. This is why he's the perfect guy for improving this crazy 12-rotor... 😎🤟
For the oil draining issue for the center rotor, could you have a timed valve that would alternate and let each side alternate vacuum to pull the oil? The valve could even be incorporated into the bronze air screens on the top of the left and right rotors. Love your videos.
