What would you guys suggest on how to get our RPMs higher? Our next three strategies are to try lighter materials (magnesium or carbon fiber), hollowed out wheels, and finally smaller diameter wheels. At this point those seem to be our only bottle necks, anything we’re over looking?
Smaller diameter titanium wheel and spray paint it white and then put a nice thick black sharpie line in order for your tachometer to get a clear reading :)
Cut a groove in the side of the Ti wheel (and make sure it still balances). Then, using the water drops as a time reference using a black and white checked board with known measurements (like they use in myth busters) you should be able to get an accurate account for the time and rotation of the wheel.
If you're asking if it would produce a sonic boom, that's a no. A spinning object doesn't produce the kind of compression force needed for a boom. A sonic boom is produced when air is compressed at a faster rate than it can expand itself. The wheel would have to be moving, not spinning. Since the wheel is a uniform shape, there's nowhere along the wheel for air to accumulate and compress. As far as producing a different pitch or tone, though... That's beyond me. I'm not familiar with that part of physics
This makes sense, took a few physics classes and somehow missed that red flag. Though this does beg the question, could you start something on fire purely from air resistance in this fashion.
@@DoubsGaming yeah, i think so. Pretty sure that's what happens when objects enter Earth's atmosphere. It's part of the reason designing spacecrafts meant for re-entry are so difficult.
You can actually hear the fan blade tips becoming supersonic on moder high bypass turbofan engines, it maes a very strange buzzing sound, so its definitely possible but in this case unlike a turbofan this wheel is completely smooth so like you say I don't think it would create any notable disturbance in the air, who knows though I'm not an aerodynamisist or an engineer
Jet engine engineer here. First, fun to see the resin wheel break into thirds, that's exactly how a disk would be expected to "burst" as it's called at my company. You can see the damage that little thing did to your machine. Imagine what would happen if a 200lb chunk of nickel broke up like that. Second, do NOT hollow out the inside. Material closest to the rotation axis is actually what is doing all the work to hold the disk together. It's also the most efficient material in terms of added strength/weight. Third, while I don't know the dimensions of your wheel, the outer diameter might already be breaking the sound barrier. A 60mm wheel would have to spin to 109k RPM for the outer edge to reach the sound barrier. As others have stated, due to the smooth outer surface, there really isn't anything to generate a shockwave and make an audible sound. This is outside my lane, but I question your speed estimation methodology. How do you know the frequency you are picking up is the once-per-rev tone and not something like the passing frequency of the bearing balls
I noticed a lot more overtones in the spectrum of the titanium wheel, too. That said, the overtones are multiples of the fundamental, so choosing a different peak frequency would halve / double the calculated RPM, so...
Try making a magnesium wheel but press fit a titanium sleeve around the outer diameter to give it more strength. Should hit crazy high RPMs as magnesium is significantly lighter than even aluminum.
The trick to ti on the band saw... 1 flood coolant, 2 brand new Lennox blade! 3 turn the band speed as low as it goes, I don't care if the Internet gave you a different speed. If it's a variable speed, turn the adjuster till the band stops moving then turn it up till it barely works. If it's a multi speed, put a vfd controller on the motor to slow it down. I've been able to turn induction motors down to 15 hz which is 1/4 speed. It might even go down to 10hz. As for the lathe, If it's a fairly heavy lathe you can take pretty heavy cuts. If you have lots of cooling like a CNC you may even be able to go a reasonable RPM. Ti likes CNC lathes. Continuous cuts are good. Thick chips are good. Prefer a feed/rev relationship over higher rpm. Thin chips are bad, high rpm is generally bad unless you have the cooling capacity. For a manual lathe use power feed and if you want to be safe use a very low rpm. Always use new sharp tools. For a milling machine, well if it's CNC use climbing cuts and a fixed feed rate, no slowing down for corners. Use healthy oversteps. A thin chips will harden the work and break the cutter faster than an abrupt 90 corner with a heavier volumetric load will. If you are manually milling, you may be able to face it. But good luck profiling it. It hates conventional cuts and heat. But climbing cuts heavy enough to punch through the work hardened surface will likely draw the work into the cutter. You can try locking the gibs and letting the leadscrew pull through the friction. But a CNC with ball nuts is just a more reliable way to work with it.
Take it from a guy who mass machines titanium on the regular, whatever speed you think you should be running at, halve it. Most machinists who are unfamiliar with the material go way too fast and destory any cutting edge you once had. Bi-metal band saw blades will cut it but have to be sharp and run slow, 300 series stainless slow. Cutting it on the lathe, use carbide and go a hair slower than stainless steel speeds.
@@76Arfa I truthfully don't have an answer for you. I am primarily a lathe operator but I can guess that cutting over a round surface can be a challenge on the jet because it gets deflected but I really don't know. Also the struggle may have just been better content.
I also cut much Ti and Inconel. When I discovered cermet inserts my life changed. Now, I ENJOY Ti, Inconel and hard machining. Maschosicism at its finest.
Agree! Titanium (especially the machinable grades) isn't hard to machine as long as you go VERY slow. I was making a titanium pen (yeah, go figure) and lost several drill bits center cutting the middle out until I realized I was just going a little too fast for the heat. I slowed down just a little and it cut beautifully. Once it starts grabbing, the heat skyrockets and something breaks. It's almost like copper, but not that gummy. Despite the hype, titanium is softer than steel, but harder to machine unless you go slow.
First, use a silver or white line for contrast to get the Tachometer to work. Also, the titanium wheel would most likely have a different resonant frequency especially since you changed the bearings. Bearings are usually the noise maker anyway and since you upgraded them the frequencies almost certainly wouldn’t correspond to the same RPMS. You very likely exceeded the RPMs of the aluminum wheel with this experiment. Keep it up, i love this stuff, it’s why i like engineering!
This is the first video of yours that I've watched and while waterjet videos don't exactly peak my interest the comedy/editing will keep me watching haha, keep it up
I'm an engineer. The limiting factor on wheel RPM is parasitic drag from air resistance and bearing friction; not the weight of the material. If you had low enough friction, the outer surface would achieve the same velocity as the jet. The best way to achieve lower air drag is to polish the surface of the wheel, and place the whole contraption in a somewhat airtight cylindrical container, so a rotating mass of air can form around it, instead of accelerating the stationary air in the room. But by far the biggest improvement could be had by removing the grease from the bearing. After all you only need it to work once.
I think I've only seen one other comment correctly pointing out that a lighter wheel wouldn't help. IDK what mechanism they're even imagining for a heavier wheel to have more drag. With good bearings, the extra weight on them should be negligible compared to air resistance. If the wheel isn't perfectly balanced on the same axis as the bearing, a lighter wheel wouldn't wobble as hard. But I think wobble must be low enough to be pretty negligible, or something would probably break at those speeds. Wheel *diameter* on the other hand is a significant factor. The outer edge of the wheel can only reach a linear speed of at most the water jet speed. The larger the wheel radius, the lower RPM for the same linear speed. Cutting a groove into the wheel (or just shrinking it) would give the water jet a higher "gear ratio" in turning the wheel. ---- Interesting idea about a housing to allow rotating air. It would still have to allow water from the water jet to escape so it couldn't be airtight everywhere, but yeah you could maybe get a shroud around it that would encourage air to move around it. (Unless you were driving the wheel by a different mechanism, like electromagnetism, like a DC motor at a distance? Then you could put it in a low-pressure / partial vacuum bell jar or something. Makes me think of some modern hard drives that use helium.)
You need a white mark on a black wheel, these tachometers don't work very well with black marks on white wheels, because they need short impulses of a light surface. But usually they don't work above 100,000 rpm....
This whole channel feels like a post-apocalyptic Waterjet Channel where a lone survivor stumbles upon the location and partial ruins of the Waterjet Channel and started making videos to keep from going insane.
10:11 If you had the world's first 100% energy transfer device; which would technically be breaking the rules of thermodynamics simply by the small distance.
Since the titanium isn't gonna get gouged out as much, to maximize the speed you are gonna want to have it hit the wheel further out so the water stream is hitting at an angle closer to tangent of the surface of the wheel.
You're giving advice to someone who can't even bother to fit a bearing properly. Also someone who's best idea for spinning wheels quickly is to unbalance them as fast as possible. Also someone who thinks puns and bad accents are the height of wit. etc.
You could possibly increase the max speed at the outer diameter by creating a tophat shaped wheel. Point the waterjet at the smaller diameter section and the larger half may move faster than the water from the jet just like higher gearing in a car. It will however be harder to spin.
I'm not a smart person, butt I love to think - that I'm a smart person. Add new batteries to the tach, (Taco) a shield for the tachometer's sensor's 'view' (+ a small, adjoining fan?) and a groove into the wheel's side for better 'traction' between the water jet and wheel. Whatever the tach 'looks at' needs to be exaggerated. BONUS! (I hope this helps)>>>Aim the jet at a smaller circumference of the wheel. HF!
The peak frequency of the fundamental tone on the Titanium sample reached a maximum of 953Hz (on my spectrogram). That equates to 57,180 RPM. I'd throw out your tachometer, and ignore any previous readings. Working out new speeds based upon the previous rpm measured with it will be giving falsely high results for everything. They can pick up false signals (harmonics) and give you twice the speed or more. Here's my measurements: *Resin + Titanium Shavings:* 429 Hz * 60 = 25,740 RPM *Copper:* 332 Hz * 60 = 19,920 RPM *Titanium:* 953 Hz * 60 = 57,180 RPM
Someone else did say that different bearings produce different sound signatures so doing another series of tests with only ceramic bearings would also give a more accurate result.
@@DoubsGaming Good call! I think the difference in sound would mostly come from higher harmonics and intermodulation (which can produce frequencies lower than the fundamental). But still, would be great to keep everything constant except for the material being tested. 👍
@@retrocompaq5212 Aye, you're right about the different sounds. I should probably make a video on this - after my audio interface is repaired for the 2nd time in a row. Differences in sound characteristics usually come from frequencies higher than the fundamental. Usually, the fundamental (1st harmonic) is the one to look at, as it'll be the one that represents the rotation speed (except in cases of strange vibrations). But usually you can see these other vibrations starting to occur in the spectrogram and ignore them.
Here's an idea to get the tachometer to read. You guys electrocuted it so it turned blue, well dip half of it In the solution so it becomes a different colour than the other half. I don't know how the tachometer exactly works, but it's how I think it does, it should be able to give a reading. And it won't rub off like the sharpie did.(I have no idea if it will actually work but it's an idea)
my guess would be the tachometer functions on contrast to generate a differential pulse wave, then just spits out pulses per second to pulses per minute to get RPM, the blue anodization may have hindered the contrast (red laser), so maybe try a white spray paint and the sharpie black line, a wider black line may be beneficial because at higher RPM the contrast would produce a fainter pulse signal for a thin one with respect to the sensors sample rate.
At the speeds they're trying to measure itd probably be best to do half black non reflective and the other half white very reflective. That way instead of trying to catch a quick blip the meter has half a rotation to sense the change in intensity. As long as its capturing one up and one down level change per rotation it will remain accurate. Also, itd be a helluva lot easier to deduce on high speed.
it did not read the speed because of the color diffrence , you can glue a white paper with a dark line on the side of the wheel. (tho in this case the water wouldnt help much.) laser readers work much better if the line is much darker than the surface , but in this case theres not much you can do but paint the wheel white. a white line would probably give somewhat innacurate reading duo to the laser being red .
If you're gonna keep bumping up the RPMs, you'll need a better measuring method. Get a very small disc magnet, drill a hole in the side of your wheel (not the circumference, it'll get thrown off, just the side, as close to the bearing as you can to avoid imbalance), JB weld it in, balance it, and then use a read head pulled out of an old tape deck, hooked to an oscilliscope, to measure the speed of the wheel. An optical tachometer just isn't gonna keep up at these speeds, although you may have better results spray painting it black, and then adding a retro-reflective white strip.
instead of a tape reader couldn't you just use any inductor or even a piece of coiled copper? the charge generated by the magnet could be detected by an oscilloscope, and since you basically made a monophase generator, you could measure the frequency of the current you generate, and instead of embedding a magnet which could cause imbalance you could electro-coat a part of it with something ferromagnetic
@@eduardopupucon Sure you could, but a tape head has the advantages of being readily available, cheap, and most importantly - has a really high frequency response. You could use any old coil of wire, but at 100khz+ ... well I'm no electrical engineer, but at some point you'll have to actually think about the design of your coil so that it can actually produce a signal at those frequencies, and why bother doing that when you can use one where someone's already done all the work for you?
It's better to treat the magnets like a small generator, whatever wattage you get out of it can be measured at lower more accurate speeds, then that wattage number can get you a good estimate on how fast its turning at higher rpm, works for 20k rpm liter bikes at least
Make sure it's perfectly balanced, I could tell just from the hand spin it was off balance since it ended up swinging back and forth around the heavy side. The imbalance is going to cause the bearings to wear unevenly and cause more friction. Use a hobby propeller balancer to get it as close as possible to perfect. I would also suggest rounding off the corners and trying to shoot for a flattened sphere shape to avoid air turbulence. Good luck!
I just commented that the heavy side is the bottom which makes it act as a pendulum. Knock a couple grams off until it goes away. Its typical to see a bunch of drilled out spots on engine crankshafts to balance them. Same could be done here. Just drill or mill off a little bit of material.
You have few things you need to work out with yourself but other than that you are somewhat entertaining to a guy who never smiles. Take that as a compliment...
I'm glad you guys decided to take the frequency of the sound.... Over just drawing a white line on the wheel, or a "tracking dot " from a 3D scanner. But you know it worked
@@Sharpless2 Drill the side, thread it and insert a bolt. Cut it flush and do the same on the other side at 180° to keep the balance. The cut bolt end could be painted to reflect the laser tachometer.
@@locouk why put painted bolts in the wheel? It is much easier and more effective if you just use black spray paint to make the whole wheel black and then paint a quarter of the wheel white
you could cut out a little tab/wing on the side of the wheel that will receive air resistance instead of water, possibly allowing you to test the sound barrier idea
That might work. It is spinning, though... You would probably have to make almost a small cupped indent on it to catch air so it can compress. I do wonder if that would work, though... 🤔
@@yourbifriendaspen3629 I feel like the drag would prevent him from getting to the speed required, I don't remember where I saw it but doesn't drag increase with speed? If that's true then in that case it might not be possible considering how fast it's going.
Im sure the harmonics would be completely different between the materials and bearings used. The pitch used between them for estimates can't be reliable
The right way to do it would be to take samples from different parts of the video, find a part where you could measure it with the tachometer, and watch the corresponding line travel left to make sure you are tracking the right one. Picking out "maximums" on a spetrograph is kind of bullshit.
Have you spun nickel metal yet? Would also be cool to see the titanium wheel lightened up and see if you can increase that spead. Maybe Nurle the outside too for extra friction with the water and media. Awesome video, now i need to convince my company to let me try some experiments 😂
As Colin Chapman once said "If you want to go faster.... just add lightness" thats your answer right there my boy. Now go get that sound barrier broken, im intrigued as to what will happen.
Check out the fitting of bearings on good downhill longboard wheels. Bearings are always a super tight fit. Also taking advantage of how durable titanium is, you should hollow it out a bit. Like a titanium whiffle ball. I think the groove it cut in those resin wheels really affected how it was spinning.
I think fully precision machining the wheel is gonna end up being a needed step to really optimize it, that oughta get some interesting results! And I wonder if machining a groove in a resin wheel and then encasing wire might be cool? That’d be a fun comparison to this wire one! Ye could even try making a batch with different material wire, maybe?
5:28 Interesting fact: In high-power rocketry they mix titanium sponge into some of the solid fuel motors and the result is a beautiful shower of sparks from the rocket as it blasts off into the sky.
"How do we measure that?" With white tape or paint. Damn. Also, SURELY you can set up a safe system to read the RPMs without having to run up to it after it's already slowed down a bit. Danger isn't entertaining regarding these types of tests...at least not to me.
Assist with air and paint it black with a white or silver mark to measure RPM . Get fingernail polish that matches the silver tape that was supplied with the tachometer. The air will serve two assisting properties. The motion and lower the pressure due to that Bernoulli thing.. You could also use an air bearing for reduced friction. Make a steel spool that fits the profile of the titanium and pump air out of the center of the spool. Replace any grease the bearing might have with WD-40. Good Luck
I hope there is a part 2 to this video where you try different kinds of lead or metals. This was top 3 of videos you have ever done in my opinion. I want to see 2 bullets fuse now and hope you get it done. Good Luck and God Bless
11:10 sound frequency was roughly 1000hz, so approximately 60,000 rpm (very roughly). So the assuming the wheel's got a diameter of around 3 inches, edge would be moving at ((1000*60*60*(3/12/5280)*3.14) which is around 530 miles an hour on the rim. Seems close to your result, of course who knows how accurate the camera's recording or my measurement are lol.
Great entertainment. I can tell you have working around this shop forever as your ability to cover all ideas or theorys with tests along with funny spats makes this very fun to watch! Great job!
m8 you are just wrong, titanium is a brilliant conductor, i make titanium knives, and you simply can't hold them for 2 grinding passes without cooling them down whereas you can make 6 in carbon steel before needing to quench, but I'm with you on the saw, takes me like 5 1mm cutting disks to cut out the shape of a 9-inch blade, and it usually kills the angle grinder, PS you can't measure it because you anodized it there is not enough color difference between the pen and background .... DOH! PPS'm also a British army-qualified gunsmith you will not get a sonic boom from it if that is what you're hoping for as it does not pass through air.
You want to make it go really really fast using the same wheel and setup? Put the wheel on a slight tilt so that the water jet can it the side of the wheel. Then accelerate the wheel to the maximum (until frequency stops climbing) like you do here, but then move the water jet head to the side of the wheel starting from the outter diameter, and moving slowly in the direction of the center. The closer to the center the faster (RPM) the wheel will go, because the water speed is constant so is the surface speed wherever the water hits the wheel, and in a smaller diameter that means higher RPM. Just remember moving the jet slowly because the inner it goes the more rotational inertia it has to overcome in order to accelerate the wheel. To mesure the RPM you can paint a white stripe in the wheel, or paint the side white and put a black stripe.
The jet could be more tangential to the wheel, because of the bigger size of the wheel. Also, the bigger the wheel, the slower the"water speed" will make it spin. Made me remember the first Mini with their small wheels and short life tires. Thank you for the content!
Okay so after a brief scroll through a handful of comments, heres the suggestions I think would be most interesting to see put together Firstly, dont annodize the wheel because that will make it harder to see the marker line. Also, as a part 2 to this one, use a white or other more vibrant color marking on the wheel Second, aim the waterjet further away from the wheel's center Titanium is much harder to gouge compared to aluminum, so if you hit the wheel closer to the edge, itll spin faster (in theory) and still wont gouge. Third, I saw this interesting suggestion of making a wheel out of Magnesium because of how light it is, and then using a layer of Titanium to encase it for added strength. In theory, not a terrible idea, so maybe try that alongside a completely titanium wheel.
Some good precision machining the bore, and balance it when your done, the balance will greatly improve your rotational speed before failure. This very cool, thanks for sharing. Cheers!
Might drill small holes into in the side and through the wheels, taking out material to lighten it up and also creating a surface that you might be able to get a reading. Just make sure every hole is precisely located to maintain balance.
I work with CNCs, and one of my customers mass produces medical components, many of which are made from titanium (since it’s 1 of 2 metals that the body won’t reject), and it’s really not that difficult to work with compared to some other really hard alloys. Just keep a steady stream of coolant on the tools, and if you can get that coolant at a really high pressure, it’ll help break a chip. Also, having the right inserts for the job really helps.
What you can do is cut the titanium wheels front to a slight conical like face instead of it being flat so that as the waterjet spins it the more in it goes to the center the faster it'll spin (may possibly break time and space with this method lol). Great video!
Imagine causality being broken, not by physicists in a deep dark secret lab, but a couple of dudes messing with a waterjet when the bosses back is turned 🤣
13:31 it wouldn’t break the sound barrier since that requires a difference in pressure. a sonic boom is caused because an object moves through a space faster than the air can fill it behind it. In this case it’s not going anywhere and so not leaving any voids to fill. But it could still be faster than the speed of sound.
I must say, i love the little monty python easter eggs too, im a long time fan of monty python and i have huge respect for anyone that appreciates that epic british humour, its the funniest shit out there in my opinion and requires a certain kind of humour and whit to enjoy 😊 this channel is gold
I think if the jet can move slightly so that once it’s spinning fast, you can make the jet that it only hits side of titanium. May get that speed. Nice video, new sub. ✌️
I mean, it would cost a ridiculous fortune, but diamond is 3.5 grams per cubic centimeter, compared to titanium's 4.5 grams per cm³ I know industrial diamond isn't the pretty crystal we're familiar with, making it a lot cheaper, but I don't know if they can make a single, monolithic piece of industrial diamond big enough.
The less mass you have far from the axis of rotation, the faster it will spin. Cut wedges out of the wheel so basically you have the bearing (including some titanium to house it), some spokes, and the outer wheel left. I don't know enough about the material properties of titanium or the specs of your waterjet to say how much you need to leave, but I'm pretty sure you could cut away almost all of it and still have enough to hold together. I saw quite a few titanium machining tips in the comments, I assume they know what they're talking about. I think a good knurling would let the water grip the wheel better, and it would also give better dynamic properties (basically, it grips the air/water around the wheel and allows for a smoother transition of fluid speed between the wheel and the surroundings).
My understanding is that titanium has a higher surface roughness than aluminum, which will increase friction and drag. It’s possible that giving the wheel a mirror finish by polishing it will increase the speed. If the wheel is slightly larger, the speed of the water jet will create the same surface rotational speed, all else being equal, leading to a lower RPM overall. It’s also the case that any increase in surface area will increase drag and lower the RPM.
I would be curious if having a more massive mounting solution would introduce more harmonic stability to the system. Your current setup seems secure yet lightweight/low mass, so it may be allowing that harmonic oscillation to leak more energy into the mounting setup. I think if you really want to get high rpms, you're going to want to clamp a high stiffness stud into an mini anvil of some kind, and get that on a thick rubber foam isolation mat. I think that could fit in your waterjet setup. The bearings are showing your other weak links now, and i bet if you put your hand on some of the mounting hardware while the wheel is as speed, it will be vibrating a lot. If you eliminate that loss, you'll eliminate some instability in the wheel rotational system👍
What would you guys suggest on how to get our RPMs higher? Our next three strategies are to try lighter materials (magnesium or carbon fiber), hollowed out wheels, and finally smaller diameter wheels. At this point those seem to be our only bottle necks, anything we’re over looking?
Rutts in the titanium
VTEC
Tungsten?
Smaller diameter titanium wheel and spray paint it white and then put a nice thick black sharpie line in order for your tachometer to get a clear reading :)
Cut a groove in the side of the Ti wheel (and make sure it still balances). Then, using the water drops as a time reference using a black and white checked board with known measurements (like they use in myth busters) you should be able to get an accurate account for the time and rotation of the wheel.
If you're asking if it would produce a sonic boom, that's a no. A spinning object doesn't produce the kind of compression force needed for a boom. A sonic boom is produced when air is compressed at a faster rate than it can expand itself. The wheel would have to be moving, not spinning.
Since the wheel is a uniform shape, there's nowhere along the wheel for air to accumulate and compress.
As far as producing a different pitch or tone, though... That's beyond me. I'm not familiar with that part of physics
This makes sense, took a few physics classes and somehow missed that red flag. Though this does beg the question, could you start something on fire purely from air resistance in this fashion.
@@DoubsGaming yeah, i think so. Pretty sure that's what happens when objects enter Earth's atmosphere. It's part of the reason designing spacecrafts meant for re-entry are so difficult.
You can actually hear the fan blade tips becoming supersonic on moder high bypass turbofan engines, it maes a very strange buzzing sound, so its definitely possible but in this case unlike a turbofan this wheel is completely smooth so like you say I don't think it would create any notable disturbance in the air, who knows though I'm not an aerodynamisist or an engineer
bearings
@@mishkamcivor409 the thunderscreech planes propellar would also make a visible shockwave because of how fast it was going
Jet engine engineer here.
First, fun to see the resin wheel break into thirds, that's exactly how a disk would be expected to "burst" as it's called at my company. You can see the damage that little thing did to your machine. Imagine what would happen if a 200lb chunk of nickel broke up like that.
Second, do NOT hollow out the inside. Material closest to the rotation axis is actually what is doing all the work to hold the disk together. It's also the most efficient material in terms of added strength/weight.
Third, while I don't know the dimensions of your wheel, the outer diameter might already be breaking the sound barrier. A 60mm wheel would have to spin to 109k RPM for the outer edge to reach the sound barrier. As others have stated, due to the smooth outer surface, there really isn't anything to generate a shockwave and make an audible sound. This is outside my lane, but I question your speed estimation methodology. How do you know the frequency you are picking up is the once-per-rev tone and not something like the passing frequency of the bearing balls
I noticed a lot more overtones in the spectrum of the titanium wheel, too. That said, the overtones are multiples of the fundamental, so choosing a different peak frequency would halve / double the calculated RPM, so...
Try making a magnesium wheel but press fit a titanium sleeve around the outer diameter to give it more strength. Should hit crazy high RPMs as magnesium is significantly lighter than even aluminum.
It would accelerate faster, but should reach the same rpm. Also be careful as magnesium fires are troublesome
wouldn't one of the materials stretch more than the other and cause significant problems?
Beryllium? although it'd be mad expensive.
I feel like *magnesium* and a *water*jet could be a funny combo
@@matthewmorgan582 They would die from berylliosis. Do not fuck with that shit.
This is the type of unhinged video that got me hooked on youtube back in its early days.
😮
we have come full circle
That wheel sounded like a alien going 80,000rpm
The trick to ti on the band saw... 1 flood coolant, 2 brand new Lennox blade! 3 turn the band speed as low as it goes, I don't care if the Internet gave you a different speed. If it's a variable speed, turn the adjuster till the band stops moving then turn it up till it barely works. If it's a multi speed, put a vfd controller on the motor to slow it down. I've been able to turn induction motors down to 15 hz which is 1/4 speed. It might even go down to 10hz. As for the lathe, If it's a fairly heavy lathe you can take pretty heavy cuts. If you have lots of cooling like a CNC you may even be able to go a reasonable RPM. Ti likes CNC lathes. Continuous cuts are good. Thick chips are good. Prefer a feed/rev relationship over higher rpm. Thin chips are bad, high rpm is generally bad unless you have the cooling capacity. For a manual lathe use power feed and if you want to be safe use a very low rpm. Always use new sharp tools. For a milling machine, well if it's CNC use climbing cuts and a fixed feed rate, no slowing down for corners. Use healthy oversteps. A thin chips will harden the work and break the cutter faster than an abrupt 90 corner with a heavier volumetric load will. If you are manually milling, you may be able to face it. But good luck profiling it. It hates conventional cuts and heat. But climbing cuts heavy enough to punch through the work hardened surface will likely draw the work into the cutter. You can try locking the gibs and letting the leadscrew pull through the friction. But a CNC with ball nuts is just a more reliable way to work with it.
Take it from a guy who mass machines titanium on the regular, whatever speed you think you should be running at, halve it. Most machinists who are unfamiliar with the material go way too fast and destory any cutting edge you once had. Bi-metal band saw blades will cut it but have to be sharp and run slow, 300 series stainless slow. Cutting it on the lathe, use carbide and go a hair slower than stainless steel speeds.
Agreed, also a steady stream of coolant on the tip of the cutting tool helps too
Is there a reason they didn't just use the water jet instead of the bandsaw for the rough cut?
@@76Arfa I truthfully don't have an answer for you. I am primarily a lathe operator but I can guess that cutting over a round surface can be a challenge on the jet because it gets deflected but I really don't know. Also the struggle may have just been better content.
I also cut much Ti and Inconel. When I discovered cermet inserts my life changed.
Now, I ENJOY Ti, Inconel and hard machining. Maschosicism at its finest.
Agree! Titanium (especially the machinable grades) isn't hard to machine as long as you go VERY slow. I was making a titanium pen (yeah, go figure) and lost several drill bits center cutting the middle out until I realized I was just going a little too fast for the heat. I slowed down just a little and it cut beautifully. Once it starts grabbing, the heat skyrockets and something breaks. It's almost like copper, but not that gummy. Despite the hype, titanium is softer than steel, but harder to machine unless you go slow.
Should have just drawn a white line on the wheel
Exactly 😂
Yeah that is what is was thinking😂
We’ll certainly give that a try. We were a bit rushed with filming and didn’t have many marking options handy.
That or a piece of tape or they could have scribed a line on
I love white lines
First, use a silver or white line for contrast to get the Tachometer to work. Also, the titanium wheel would most likely have a different resonant frequency especially since you changed the bearings. Bearings are usually the noise maker anyway and since you upgraded them the frequencies almost certainly wouldn’t correspond to the same RPMS. You very likely exceeded the RPMs of the aluminum wheel with this experiment. Keep it up, i love this stuff, it’s why i like engineering!
My first thought was using a white paint marker. Nice
This. Guaranteed the frequencies are different being a different material with different bearings as well
This is the first video of yours that I've watched and while waterjet videos don't exactly peak my interest the comedy/editing will keep me watching haha, keep it up
*pique
I like your sense of humor.
Makes me feel at home.
I'm an engineer. The limiting factor on wheel RPM is parasitic drag from air resistance and bearing friction; not the weight of the material. If you had low enough friction, the outer surface would achieve the same velocity as the jet. The best way to achieve lower air drag is to polish the surface of the wheel, and place the whole contraption in a somewhat airtight cylindrical container, so a rotating mass of air can form around it, instead of accelerating the stationary air in the room. But by far the biggest improvement could be had by removing the grease from the bearing. After all you only need it to work once.
I think I've only seen one other comment correctly pointing out that a lighter wheel wouldn't help.
IDK what mechanism they're even imagining for a heavier wheel to have more drag. With good bearings, the extra weight on them should be negligible compared to air resistance. If the wheel isn't perfectly balanced on the same axis as the bearing, a lighter wheel wouldn't wobble as hard. But I think wobble must be low enough to be pretty negligible, or something would probably break at those speeds.
Wheel *diameter* on the other hand is a significant factor. The outer edge of the wheel can only reach a linear speed of at most the water jet speed. The larger the wheel radius, the lower RPM for the same linear speed.
Cutting a groove into the wheel (or just shrinking it) would give the water jet a higher "gear ratio" in turning the wheel.
----
Interesting idea about a housing to allow rotating air. It would still have to allow water from the water jet to escape so it couldn't be airtight everywhere, but yeah you could maybe get a shroud around it that would encourage air to move around it.
(Unless you were driving the wheel by a different mechanism, like electromagnetism, like a DC motor at a distance? Then you could put it in a low-pressure / partial vacuum bell jar or something. Makes me think of some modern hard drives that use helium.)
Im also an engineer, they need to use ceramic bearings if they want to achieve such high rpms with lower friction.
@@xxn0cturn3xxWhy ceramic and not tungsten carbide ?
@@xxn0cturn3xx They are using ceramic bearings lol
@@RovingPunster better yet, why not sapphire bearings?
Bearing will affect the sound/harmonics. Can’t use the previous frequency. Next time don’t anodize it so there is more contrast for the meter!!
or heavily anodize half the wheel to create contrast that stays on.
A white line on the black wheel would have worked just fine.
Or to just grind off the anodize in a line
@@minimalskill6592 minimal skill but maximum brain
You need a white mark on a black wheel, these tachometers don't work very well with black marks on white wheels, because they need short impulses of a light surface.
But usually they don't work above 100,000 rpm....
This whole channel feels like a post-apocalyptic Waterjet Channel where a lone survivor stumbles upon the location and partial ruins of the Waterjet Channel and started making videos to keep from going insane.
Yeah, wtf happend to the channel?
The good people left and the channel died
they never made a video about it makes me think the channel and the other guys parted on bad terms?
@@xJagaimo I heard somewhere that they moved to a different position or something, it’s just not that good without them tho
0:10 I laughed way too hard and I have no idea why lmao
ONE DAY I WAS BORN
IKR! You're not the only one 😂😂😂
Probably the skulls 💀💀
the fuckin skulls 💀🔄
10:11 If you had the world's first 100% energy transfer device; which would technically be breaking the rules of thermodynamics simply by the small distance.
Since the titanium isn't gonna get gouged out as much, to maximize the speed you are gonna want to have it hit the wheel further out so the water stream is hitting at an angle closer to tangent of the surface of the wheel.
Also it would likely be a good idea to move the jet away from the axis as the wheel expands.
You're giving advice to someone who can't even bother to fit a bearing properly. Also someone who's best idea for spinning wheels quickly is to unbalance them as fast as possible. Also someone who thinks puns and bad accents are the height of wit. etc.
@@amarissimus29 yes because you are much more capable funny witty etc....get a grip
@@amarissimus29I bet you still get invited to all the parties and end up with all the beautiful women.
You could possibly increase the max speed at the outer diameter by creating a tophat shaped wheel. Point the waterjet at the smaller diameter section and the larger half may move faster than the water from the jet just like higher gearing in a car. It will however be harder to spin.
11:00 you know it’s crazy when your water starts sparking
I'm not a smart person, butt I love to think - that I'm a smart person. Add new batteries to the tach, (Taco) a shield for the tachometer's sensor's 'view' (+ a small, adjoining fan?) and a groove into the wheel's side for better 'traction' between the water jet and wheel. Whatever the tach 'looks at' needs to be exaggerated. BONUS! (I hope this helps)>>>Aim the jet at a smaller circumference of the wheel. HF!
Okay, well, guess I was late with my ideas. Taco Meter, though - that could be funny. Ha ha ha 🥐🥓🌮
The peak frequency of the fundamental tone on the Titanium sample reached a maximum of 953Hz (on my spectrogram). That equates to 57,180 RPM.
I'd throw out your tachometer, and ignore any previous readings. Working out new speeds based upon the previous rpm measured with it will be giving falsely high results for everything. They can pick up false signals (harmonics) and give you twice the speed or more.
Here's my measurements:
*Resin + Titanium Shavings:*
429 Hz * 60 = 25,740 RPM
*Copper:*
332 Hz * 60 = 19,920 RPM
*Titanium:*
953 Hz * 60 = 57,180 RPM
@ 12:50 in the video, the peak reading is ~924 Hz, which equates to 55,440 RPM.
@ 13:02 in the video, peak reading is ~1320 Hz = 79,200 RPM.
Someone else did say that different bearings produce different sound signatures so doing another series of tests with only ceramic bearings would also give a more accurate result.
@@DoubsGaming denser materials sounds different too
@@DoubsGaming Good call! I think the difference in sound would mostly come from higher harmonics and intermodulation (which can produce frequencies lower than the fundamental). But still, would be great to keep everything constant except for the material being tested. 👍
@@retrocompaq5212 Aye, you're right about the different sounds. I should probably make a video on this - after my audio interface is repaired for the 2nd time in a row.
Differences in sound characteristics usually come from frequencies higher than the fundamental. Usually, the fundamental (1st harmonic) is the one to look at, as it'll be the one that represents the rotation speed (except in cases of strange vibrations). But usually you can see these other vibrations starting to occur in the spectrogram and ignore them.
Here's an idea to get the tachometer to read. You guys electrocuted it so it turned blue, well dip half of it In the solution so it becomes a different colour than the other half. I don't know how the tachometer exactly works, but it's how I think it does, it should be able to give a reading. And it won't rub off like the sharpie did.(I have no idea if it will actually work but it's an idea)
Tachometers like that usually use reflective tape strips that you put on the object to have a stable signal
The proper thing would be to put a retroreflective strip on it.
@@RIGeek. Most laser tachometers even come with some
@@RIGeek.Can't. You can't put anything on or take anything away.
IF it sticks, it causes a disbalans which is very dangerous at those speeds.
This idea of discoloration is kinda decent does not have to be 50% of the wheel consider 5% to 10% to get some kind of stripe.
my guess would be the tachometer functions on contrast to generate a differential pulse wave, then just spits out pulses per second to pulses per minute to get RPM, the blue anodization may have hindered the contrast (red laser), so maybe try a white spray paint and the sharpie black line, a wider black line may be beneficial because at higher RPM the contrast would produce a fainter pulse signal for a thin one with respect to the sensors sample rate.
or anodise just half very dark....
At the speeds they're trying to measure itd probably be best to do half black non reflective and the other half white very reflective. That way instead of trying to catch a quick blip the meter has half a rotation to sense the change in intensity. As long as its capturing one up and one down level change per rotation it will remain accurate. Also, itd be a helluva lot easier to deduce on high speed.
"Uhhhhh, I know! I'll just leave it on the ground!"
Sent me to space, MY SIDES
it did not read the speed because of the color diffrence , you can glue a white paper with a dark line on the side of the wheel. (tho in this case the water wouldnt help much.)
laser readers work much better if the line is much darker than the surface , but in this case theres not much you can do but paint the wheel white.
a white line would probably give somewhat innacurate reading duo to the laser being red .
If you're gonna keep bumping up the RPMs, you'll need a better measuring method. Get a very small disc magnet, drill a hole in the side of your wheel (not the circumference, it'll get thrown off, just the side, as close to the bearing as you can to avoid imbalance), JB weld it in, balance it, and then use a read head pulled out of an old tape deck, hooked to an oscilliscope, to measure the speed of the wheel. An optical tachometer just isn't gonna keep up at these speeds, although you may have better results spray painting it black, and then adding a retro-reflective white strip.
instead of a tape reader couldn't you just use any inductor or even a piece of coiled copper? the charge generated by the magnet could be detected by an oscilloscope, and since you basically made a monophase generator, you could measure the frequency of the current you generate, and instead of embedding a magnet which could cause imbalance you could electro-coat a part of it with something ferromagnetic
another idea would be to find a way to couple the wheel into a car alternator, that way you already have everything built into
@@eduardopupucon Sure you could, but a tape head has the advantages of being readily available, cheap, and most importantly - has a really high frequency response. You could use any old coil of wire, but at 100khz+ ... well I'm no electrical engineer, but at some point you'll have to actually think about the design of your coil so that it can actually produce a signal at those frequencies, and why bother doing that when you can use one where someone's already done all the work for you?
It's better to treat the magnets like a small generator, whatever wattage you get out of it can be measured at lower more accurate speeds, then that wattage number can get you a good estimate on how fast its turning at higher rpm, works for 20k rpm liter bikes at least
Make sure it's perfectly balanced, I could tell just from the hand spin it was off balance since it ended up swinging back and forth around the heavy side. The imbalance is going to cause the bearings to wear unevenly and cause more friction. Use a hobby propeller balancer to get it as close as possible to perfect. I would also suggest rounding off the corners and trying to shoot for a flattened sphere shape to avoid air turbulence. Good luck!
I just commented that the heavy side is the bottom which makes it act as a pendulum. Knock a couple grams off until it goes away. Its typical to see a bunch of drilled out spots on engine crankshafts to balance them. Same could be done here. Just drill or mill off a little bit of material.
Legend has it the wheel spins faster than Sonic
Lol😊
Go away Walter!
waltuh you aint supposed to be here waltuh
You have few things you need to work out with yourself but other than that you are somewhat entertaining to a guy who never smiles. Take that as a compliment...
I'm glad you guys decided to take the frequency of the sound.... Over just drawing a white line on the wheel, or a "tracking dot " from a 3D scanner. But you know it worked
Where did the original guys go?
Gone, reduced to atoms
Sold the channel
They licked the wrong substances.
Yeah wtf I really miss them
Retired I guess?
Try using a fan to clear the water mist
Also, thread a reflective bolt into the side so you can get an accurate tachometer reading.
that would unbalance the wheel very badly and would increase the mass. Both of those things would yield much lower RPM.
@@Sharpless2
Drill the side, thread it and insert a bolt. Cut it flush and do the same on the other side at 180° to keep the balance.
The cut bolt end could be painted to reflect the laser tachometer.
@@locouk why put painted bolts in the wheel? It is much easier and more effective if you just use black spray paint to make the whole wheel black and then paint a quarter of the wheel white
@@Henning_S. Easy, cheap, and will work a treat. I think many are overthinking this.
@@locouk The bolt will definitely have a different density to the titanium so that would unbalance the wheel a lot
you could cut out a little tab/wing on the side of the wheel that will receive air resistance instead of water, possibly allowing you to test the sound barrier idea
That might work. It is spinning, though... You would probably have to make almost a small cupped indent on it to catch air so it can compress.
I do wonder if that would work, though... 🤔
@@yourbifriendaspen3629 I feel like the drag would prevent him from getting to the speed required, I don't remember where I saw it but doesn't drag increase with speed? If that's true then in that case it might not be possible considering how fast it's going.
@@DoubsGaming I'm not sure, actually. It's definitely affected by speed, though. I'll look it up
@@DoubsGaming yeah, drag increases with speed.
@@yourbifriendaspen3629 it will increase but with testing there might be a sweet spot on size of resistance
The next time, please do the hardest metal in the world, Tungsten
It’s brittle
It accounts as ALL OF IT. -certified googler here.
I wonder if this sort of thing will end up being turned into an actual manufacturing process to go along casting and stamping ...
Im sure the harmonics would be completely different between the materials and bearings used. The pitch used between them for estimates can't be reliable
The right way to do it would be to take samples from different parts of the video, find a part where you could measure it with the tachometer, and watch the corresponding line travel left to make sure you are tracking the right one. Picking out "maximums" on a spetrograph is kind of bullshit.
It's not a waterjet channel video without a taste test. Good job.
2:30 I think it also helps that they're constantly showering the workpieces in hundreds of liters of coolant per minute
Some bullets spin close to 300,000 RPM in flight. It's crazy how they stay together without exploding as soon as they leave the barrel.
RIP Dr Pepper who made the ultimate sacrifice for this video
1:51 "I turned my camera too late but this is just what happened: uyumymiprr khhh"
Have you spun nickel metal yet? Would also be cool to see the titanium wheel lightened up and see if you can increase that spead. Maybe Nurle the outside too for extra friction with the water and media.
Awesome video, now i need to convince my company to let me try some experiments 😂
Nurgle!?
Heresy!!!
As Colin Chapman once said "If you want to go faster.... just add lightness" thats your answer right there my boy. Now go get that sound barrier broken, im intrigued as to what will happen.
20 mph is not the speed limit it is the frequency of your barrier 13:43
Check out the fitting of bearings on good downhill longboard wheels. Bearings are always a super tight fit. Also taking advantage of how durable titanium is, you should hollow it out a bit. Like a titanium whiffle ball. I think the groove it cut in those resin wheels really affected how it was spinning.
I think fully precision machining the wheel is gonna end up being a needed step to really optimize it, that oughta get some interesting results! And I wonder if machining a groove in a resin wheel and then encasing wire might be cool? That’d be a fun comparison to this wire one! Ye could even try making a batch with different material wire, maybe?
5:28 Interesting fact: In high-power rocketry they mix titanium sponge into some of the solid fuel motors and the result is a beautiful shower of sparks from the rocket as it blasts off into the sky.
"then i decided that i didn't like how few cuts i had on my hands and wanted to change that" LOLOL! 5:38 mark. too funny!
Haven't seen Strongbad in a hot minute
Next time use Liquid Paper. A black Sharpie over a dark surface won't work.
Ok that was really cool
Was not expecting a flashback to my childhood 1 minute into a water jet channel video
0:57 strong bad fqhwgahds reference???!!
as a former homestar runner addict you got me good
"How do we measure that?" With white tape or paint. Damn. Also, SURELY you can set up a safe system to read the RPMs without having to run up to it after it's already slowed down a bit. Danger isn't entertaining regarding these types of tests...at least not to me.
Pfft, the entertainment level is directly proportional to the danger level.
This whole video gives off unintelligent energy.
Does anyone know what happened to the original hosts of this channel?
You COULD call on the slomoguys.
Assist with air and paint it black with a white or silver mark to measure RPM . Get fingernail polish that matches the silver tape that was supplied with the tachometer. The air will serve two assisting properties. The motion and lower the pressure due to that Bernoulli thing.. You could also use an air bearing for reduced friction. Make a steel spool that fits the profile of the titanium and pump air out of the center of the spool. Replace any grease the bearing might have with WD-40. Good Luck
I hope there is a part 2 to this video where you try different kinds of lead or metals. This was top 3 of videos you have ever done in my opinion. I want to see 2 bullets fuse now and hope you get it done. Good Luck and God Bless
I broke the titanium rods in my back😅
Is that where your name comes from 🤔
@@WaterjetChannel yes I got tired of hearing myself say it
11:10 sound frequency was roughly 1000hz, so approximately 60,000 rpm (very roughly). So the assuming the wheel's got a diameter of around 3 inches, edge would be moving at ((1000*60*60*(3/12/5280)*3.14) which is around 530 miles an hour on the rim. Seems close to your result, of course who knows how accurate the camera's recording or my measurement are lol.
Good job bro
The Cheat is to the Limit, cmon fhqwhgads .
You know me...
Great entertainment. I can tell you have working around this shop forever as your ability to cover all ideas or theorys with tests along with funny spats makes this very fun to watch! Great job!
Holy shit man You deserve your own show!! This is awesomeness🎉 You sir have just gained a huge fan:) Not like a fan fan, a fan😅
11:23 someone in the comments could probably calculate the RPM based on the sound pitch or something
nice job 😁
m8 you are just wrong, titanium is a brilliant conductor, i make titanium knives, and you simply can't hold them for 2 grinding passes without cooling them down whereas you can make 6 in carbon steel before needing to quench, but I'm with you on the saw, takes me like 5 1mm cutting disks to cut out the shape of a 9-inch blade, and it usually kills the angle grinder, PS you can't measure it because you anodized it there is not enough color difference between the pen and background .... DOH! PPS'm also a British army-qualified gunsmith you will not get a sonic boom from it if that is what you're hoping for as it does not pass through air.
You want to make it go really really fast using the same wheel and setup? Put the wheel on a slight tilt so that the water jet can it the side of the wheel. Then accelerate the wheel to the maximum (until frequency stops climbing) like you do here, but then move the water jet head to the side of the wheel starting from the outter diameter, and moving slowly in the direction of the center. The closer to the center the faster (RPM) the wheel will go, because the water speed is constant so is the surface speed wherever the water hits the wheel, and in a smaller diameter that means higher RPM. Just remember moving the jet slowly because the inner it goes the more rotational inertia it has to overcome in order to accelerate the wheel. To mesure the RPM you can paint a white stripe in the wheel, or paint the side white and put a black stripe.
The jet could be more tangential to the wheel, because of the bigger size of the wheel.
Also, the bigger the wheel, the slower the"water speed" will make it spin.
Made me remember the first Mini with their small wheels and short life tires.
Thank you for the content!
Okay so after a brief scroll through a handful of comments, heres the suggestions I think would be most interesting to see put together
Firstly, dont annodize the wheel because that will make it harder to see the marker line. Also, as a part 2 to this one, use a white or other more vibrant color marking on the wheel
Second, aim the waterjet further away from the wheel's center Titanium is much harder to gouge compared to aluminum, so if you hit the wheel closer to the edge, itll spin faster (in theory) and still wont gouge.
Third, I saw this interesting suggestion of making a wheel out of Magnesium because of how light it is, and then using a layer of Titanium to encase it for added strength. In theory, not a terrible idea, so maybe try that alongside a completely titanium wheel.
Fascinating. I'm not a skater (73) and it's 3:45 am. Watched the whole video in the middle of the night. LOL
Some good precision machining the bore, and balance it when your done, the balance will greatly improve your rotational speed before failure. This very cool, thanks for sharing. Cheers!
Safety guy: "I can build a boom for the tachometer"
"Naw it's good I'll take the grenade for science!"
Might drill small holes into in the side and through the wheels, taking out material to lighten it up and also creating a surface that you might be able to get a reading.
Just make sure every hole is precisely located to maintain balance.
Wouldn't a lubricated bushing be more effective for those speeds than bearings ?
"oh I know! I'll just put it on the ground."
I spat me drink at that gold right there
I work with CNCs, and one of my customers mass produces medical components, many of which are made from titanium (since it’s 1 of 2 metals that the body won’t reject), and it’s really not that difficult to work with compared to some other really hard alloys. Just keep a steady stream of coolant on the tools, and if you can get that coolant at a really high pressure, it’ll help break a chip. Also, having the right inserts for the job really helps.
7:17 nice pun with the earth/ground wire!
Paint the surface white, before marking it? Validate the capabilities of the RPM counter?
There is a fine line between genius and insanity, good luck with your travels
4:42
Neko seek: I mean I’m dangerous enough to put a bomb in my stomach to see if I would survive but not this.
Neko seek: nvm it didn’t explode
What you can do is cut the titanium wheels front to a slight conical like face instead of it being flat so that as the waterjet spins it the more in it goes to the center the faster it'll spin (may possibly break time and space with this method lol). Great video!
Imagine causality being broken, not by physicists in a deep dark secret lab, but a couple of dudes messing with a waterjet when the bosses back is turned 🤣
Finally, someone tackling the BIG questions!
Those laser tachometers usually come with a few little reflective stick on tape markers for such cases like this
12am: i should probably go to bed now
2am: Well well well, lets see what happens when you spin a titanium wheel at supersonic speeds!
No amount of money would make me get my hands that close to a screeching titanium cylinder.
13:31 it wouldn’t break the sound barrier since that requires a difference in pressure. a sonic boom is caused because an object moves through a space faster than the air can fill it behind it. In this case it’s not going anywhere and so not leaving any voids to fill. But it could still be faster than the speed of sound.
Love the slapstick interludes, lad
I must say, i love the little monty python easter eggs too, im a long time fan of monty python and i have huge respect for anyone that appreciates that epic british humour, its the funniest shit out there in my opinion and requires a certain kind of humour and whit to enjoy 😊 this channel is gold
The energy in that 80k RPM titanium spinning wheel is off the chart. Enough to kill people behind body armour.
FYI, when you're cutting titanium, prevent the shavings from catching fire. The fumes can be quite dangerous to inhale and can burn extremely bright.
7:16
"just leave it on the ground"
just froze my brain
I think if the jet can move slightly so that once it’s spinning fast, you can make the jet that it only hits side of titanium. May get that speed. Nice video, new sub. ✌️
You didn’t turn on the built in lubrication on your bandsaw while cutting titanium?
11:04 it sounds like a sports car
I mean, it would cost a ridiculous fortune, but diamond is 3.5 grams per cubic centimeter, compared to titanium's 4.5 grams per cm³
I know industrial diamond isn't the pretty crystal we're familiar with, making it a lot cheaper, but I don't know if they can make a single, monolithic piece of industrial diamond big enough.
have you calculated the water speed to know if with this pressure it even possible to acheave soun barrier
The less mass you have far from the axis of rotation, the faster it will spin. Cut wedges out of the wheel so basically you have the bearing (including some titanium to house it), some spokes, and the outer wheel left. I don't know enough about the material properties of titanium or the specs of your waterjet to say how much you need to leave, but I'm pretty sure you could cut away almost all of it and still have enough to hold together. I saw quite a few titanium machining tips in the comments, I assume they know what they're talking about. I think a good knurling would let the water grip the wheel better, and it would also give better dynamic properties (basically, it grips the air/water around the wheel and allows for a smoother transition of fluid speed between the wheel and the surroundings).
My understanding is that titanium has a higher surface roughness than aluminum, which will increase friction and drag. It’s possible that giving the wheel a mirror finish by polishing it will increase the speed.
If the wheel is slightly larger, the speed of the water jet will create the same surface rotational speed, all else being equal, leading to a lower RPM overall.
It’s also the case that any increase in surface area will increase drag and lower the RPM.
I would be curious if having a more massive mounting solution would introduce more harmonic stability to the system. Your current setup seems secure yet lightweight/low mass, so it may be allowing that harmonic oscillation to leak more energy into the mounting setup.
I think if you really want to get high rpms, you're going to want to clamp a high stiffness stud into an mini anvil of some kind, and get that on a thick rubber foam isolation mat.
I think that could fit in your waterjet setup. The bearings are showing your other weak links now, and i bet if you put your hand on some of the mounting hardware while the wheel is as speed, it will be vibrating a lot. If you eliminate that loss, you'll eliminate some instability in the wheel rotational system👍