Fog testing 3D printer part fan ducts with lights, lasers & **sparkles**

[@SianaGearz]

Congratulations on glitterbombing yourself, you're one of us now.

[@NeedItMakeIt]

I'm still trying to clean it up, I'm just lucky my kids haven't seen it. I'm going to try using mica powder next time, I had no idea it was already used for fluid testing, very cool!

[@jjptech]

Finally!! someone makes a proper flow test other than water testing

[@NeedItMakeIt]

I'm trying! I think we can level up these tests even more, there are some great ideas here in the comments. Using a laser level is a great one, I can find way to set a vertical line from the side, that would be so cool and might give much more clear info than what I was able to do, if that doesn't work, I can also create a shield with a slit in it for the flashlight too!

[@timlong7289]

Perhaps the un-asked question is: "what is the goal"? If you consider bridges, where is it important to focus the cooling air? Perhaps "at the nozzle" is not the right answer?

[@JohnDoe-fk6id]

for bridges in particular, you want to cool the extruded filament as quickly as possible, as close to the exit of the nozzle as possible, to prevent it from drooping. So "at the nozzle" is going to be pretty close. It's going to be an experimental approach to figure out how to get as much air THROUGH that area, in order to maximize the cooling effect, without cooling the nozzle itself, or driving the filament downward.

[@NeedItMakeIt]

Great question! The general goal is for best overall cooling performance on all sides and on all types of parts. For more fidelity on tie issues, it gets tough, especially with bridges, we have the initial cooling, but then we have the subsequent layers as well, when the 2nd layer is placed, it reheats the first and causes defects. From my understanding so far, with a bridge, we need fast cooling but it can't force the filament sideways or down too much, the single duct did really well with the bridges but so did the medusa version. More testing is needed to know the main areas to focus on for the best overall cooling performance on a high speed printer. Like anything there are lots of variables, so I'll try to limit as many as I can.

[@Kentrilek]

@@JohnDoe-fk6id so maybe wider ends of ducts? the same mass of air will flow around the object but with less velocity (less pressure). Another thing is direction of air flow. Up would be best but maybe parallel? pointing down is not the best I think. but for bridges dont you think that this should be adjust in slicer? thiner line with less material flow to pull it at straight line from point A to point B. Less mass will prevent drooping. Depending of viscocity of the material.

[@cosmic_cupcake]

That´s a very good question, because printing speed also matters here. Especially on ultra-fast printers you want some air to spill out away from the nozzle to continue cooling a location as the printhead is moving away, while slower printers benefit more from focusing everything on the nozzle directly.

[@igiannakas]

One thing to consider is also the spread of the air. The nozzle doesn’t remain static while it’s printing through the print area - and in particular with a fast printer you’re spending milliseconds over one specific spot. So you really want to be spreading the cooling also around the nozzle both before and after it in all directions to allow for residual heat to be dissipated after the nozzle has moved on. Basically also consider speed and time as a variable and while these tests are excellent, I feel that this is the next step in optimising the duct design. That’s why also wider opening ducts work quite well - cause they dissipate air in a larger area around the print head.

[@gabriel3437gfcxg]

you should try making a cheap schlieren imaging setup. relatively easy to do, and in my opinion yields better results. :)

[@Andre_M_3D]

Great video. I am sure a lot of us went oh oh when you poured those sparkles in the bowl and then hit it with it with all that air. Lol. Those sparkles are so hard to get rid of. Good luck! 😊.

[@dennisgignac5103]

As an Engineer, I commend you !!! Thank you

[@75keg75]

14:11 8 yrs later you’ll still be finding that stuff!!

[@thejoetandy]

craft herpes

[@NeedItMakeIt]

Brutal. I had sparkles all over me, on my face somehow as well. I just need to make sure my kids don't find it!

[@kitizz548]

In your pondering about why they would waste the CPAP power using a tube, etc. I’m guessing that they needed to make the extruding head lighter, and so moving the fan to the case and connecting it via a duct was the chosen solution. And so _because of_ all the losses in flow through the tube, they needed to source a fan capable of compensating. And little PC fans are just not capable of the required pressures. So CPAP was likely the best off the shelf solution around. And bonus points for the marketing having a new cool edge to it 😄

[@thenextlayer]

Great video, love your thorough research. May I suggest you add chapters to your videos though?

[@Taterstyles]

Something that would work better than the sparkles would be pearlescent pigments that people use for resin and things like that. It's a much finer powder with varying color shifts that display motion very well. For an example look up and Dip Your Car videos where they use a mixer to stir.

[@brunocb3]

Make a cover for the flashlight with one thin slit that allows it to project light in a line and maybe you can get something like a cross section of the fog. Or try to use a levelling laser. Adding some LEDs inside the ducts could be interesting. Maybe it won't get useful results but could look cool. About the moving glitter, you are losing a battle against KZbin's compression. I would recommend higher resolution/framerate or providing access to the raw video files.

[@NeedItMakeIt]

That's a great idea! I could easily print a cover to fit over it. I'll have to find a way to get laser level in there to see if it it could work. I have one but it's a little bit large, cool idea though! I'll switch from glitter to Mica powder to see if that helps, good call on that.

[@avejst]

Great test Impressive amount of work. wow Thanks for sharing your experiences with all of us :-)

[@NeedItMakeIt]

Thanks! I wish I could have made a bit more progress, I'll see if I can refine it a bit and focus more to give an even better idea of what's happening. I'd really love to know exactly what contributes the most to cool our part fast and evenly. I was watching a high speed Benchy print two days ago and the Pipe was wobbling around wayyy too much, it looked like a twizzler. Cooling on the Hull wasn't perfect either, so I'm curious about what ideas people will bring to the competition.

[@andyb7754]

Very interesting. My first 2 printers were FLSUN printers, a cube and a delta. Both were the biggest pieces of crap I've used. The next one was a Creality 3 V2, which I did a few mods to and it worked GREAT (still working). I bought a second, same mods and used them until YOU reviewed the QIDI Q1 Pro. I bought the Q1 Pro from the link that you had and have been very, very impressed!! How about some more videos on the Q1 Pro and QIDI slicer? Gave the 2 Creality 3 V2 printers to my son and Grandson. Yes, I'm a subscriber and a Patreon member of yours. Thank you for your videos.

[@shawnodell4382]

A duct modeled from the turbine of a turbocharger would be interesting.

[@phizc]

It would be cool to repeat the smoke test with a line laser. Have a horizontal line/light fan below the nozzle and have the camera directly below the nozzle filming straight up. Not sure how much it would show, but it would probably look really cool.

[@NeedItMakeIt]

I wanted to do this, I didn't plan well enough because the laser I bought was too long to fit. I could put a hole in the printer now that I think of it to get the laser mounted in there, that might work really well.

[@mab4110]

Schlieren imaging would be perfect for these tests.

[@avibank]

Very cool. Saddle video when?

[@dnvm84]

Thank you for doing such a detailed test and video. My biggest issue with your test is 98% of the printers on the market do not have a fan as powerful as you are testing with. Air like water always finds the least restricted way out. So with a less powerful fan there will be less of an equal distribution to all ducts depending on the design.

[@NeedItMakeIt]

It's a great point, we'll be testing and adapting these ideas to work with any fan design. The CAP fan is also an option that could be added to just about any 3D printer and it wouldn't have to be as large as the one I've show either.

[@grasstreefarmer]

That's not really true. Fluids flow through all paths at the same relative pressure drop. Or, total fluid presure is devided equally among all paths. If all paths are not equal restriction then their flow rates will vary. For one path to have half the flow rate of another from an equal pressure source it needs to be 4 times as restrictive. A lower pressure source like a smaller fan will have a lower total flow rate but the proportional flow of each path will be the same as for the higher pressure fan.

[@dnvm84]

@@grasstreefarmer Thank you for the reply. With a standard fan, do you think you will get equal flow out of all of the nozzles of the Medusa? I would think that the air would find the path of least resistance. Yes/No?

[@aaronhambek6362]

@@dnvm84I took a fluids class and he’s right, it’s just positive pressure on one side and ambient pressure on the other for all holes, it will flow out of all of them relatively equally even if one is slightly less restrictive than the others. So the path of least resistance will have more flow, but not by much necessarily

[@dnvm84]

@@aaronhambek6362 Thank you for the information.

[@anon_y_mousse]

Yeah, it definitely needs a smoother tube to get good flow. The offset nozzles are creating a tornado in the chamber, which is really cool on such a tiny scale. It might be worth testing that out more just to have fun. And now you know that glitter is always a mistake. 🤣

[@NeedItMakeIt]

I was thinking about using resin to coat the inside, any other ideas on that? Ideally I'd have a high temp resin and it could be printed with the resin printer instead, but I only have generic resin and I don't think it would last with the heat. Glitter was a big mistake, I am still finding it everywhere, occasionally it get onto my face even now. I have a new and better option that should be arriving tomorrow, it should do a far better job of showing the flow and it shouldn't make me lose my mind trying to clean it afterward either!

[@anon_y_mousse]

@@NeedItMakeIt Would it be possible to mount the fan on the main gantry so that you could use a short solid piece of tubing?

[@rynnjacobs8601]

Have you thought about using a split-lamp or a line-laser? This should give a cut through the fog.

[@mikebergman1817]

This is pretty freaking genius.

[@NeedItMakeIt]

Thanks man! It was a heck of a lot more work than I picture it would be, but now that we have it setup, we can really dial it in and get even better information. The laser level idea is really cool I want to try that today to see what it looks like. Using mica in water is another one, the sparkles mainly sunk and weren't very even, so mica could be the go-to for that type of test. I think a large dish could be good too.

[@xibatamadness31]

loving this new serie

[@NeedItMakeIt]

Awesome, we have quite a few really cool designs already submitted for the competition and I have some very interesting new equipment coming too so we can gain an even better understanding of what's really happening.

[@Bricksniper]

I wonder how well a Schlieren imaging technique would work for this. Either way, this was a good way to help visualize the airflow for 3d printing ducts.

[@NeedItMakeIt]

I had never heard or that method until about a week ago, and it's so awesome, I'll have to do some research and see how it would be possible to do it, I saw a bit of the video from Veritasium, I'll do a re-watch tonight! The smoke worked, and I'll find some ways to make it better, I think using several lights across the back could work, and a better way to extract the fog more evenly from top and bottom would be better too.

[@Bricksniper]

@@NeedItMakeIt Material wise, a simple Schlieren setup would be pretty easy. A parabolic mirror, a point light source (like a single LED), and a razor blade. The parabolic mirror is placed behind the object, and the LED would be pointed towards it. The razor blade would be placed right in front of the camera lens as to "cut" the image in half. This method is mainly used to visualize supersonic waves and thermal changes in the air, but I've seen it used for visualizing slower air flow too. As long as the fluid medium density is changing due to pressure, temperature, speed, etc, this method should work. I just thought of this as I watched Michael Rechtin's recent video of 3D Printing a supersonic nozzle and visualizing the mach speeds it was achieving.

[@SOHCHEAD]

I think this is a good way of identifying the airflow shape coming from the vents, as others have asked, I’m not sure how these changes will affect the prints themselves. Dry ice was mentioned and I think that would be a better solution for testing while printing. I am wondering if the temperature change will make a major change as well from the ice. I’ve yet to see anyone deep dive into vent design as you’ve started doing, I ended up getting a panda myself and noticed improvements but nothing drastic. They seem to have addressed the captured powder issue during mfg. Excellent start!

[@NeedItMakeIt]

I'm not100% sure yet. My initial thought is that the air needs to pickup some of that heat from the filament and part and then move away as quickly as possible so that new cool air can come in. I'm not sure it's that simple, we're trying to both cool the filament and cool the part with this setup, and that's where I can't quite figure out how to do it all. I think with some different duct designs and a bit more tests we can get a better sense. I'm not sure how much a little bit of air circulation will provide, since that air will also be slightly warm, it'd be better than nothing, but nothing compared to what we'd do when we try to cool our food down by blowing on it. TBH, I wasn't fully satisfied with all of this testing, I wish I could have seem a bit more and drawn some more concrete conclusions too. It comes down as well to my understanding... or lack of understanding of Fluid Dynamics. I certainly need some help!

[@SOHCHEAD]

@@NeedItMakeIt I think by far the most important part of this series so far is that you saw a potential for significant improvement and even without a solid path, you took what intuition made sense and put together testing to address that. The first tests were with water but that was arguably a planar representation of flow at a certain distance. The smoke added additional dimensions to your analysis but you have limitations in what is available. An ANSYS expert etc in the hivemind would be very useful here. Fluid dynamics was not my strongest course in getting my BSME, it’s worth cracking out the books though. I think this is arguably one of the most slept on aspects of 3D Printer design from a feasibility perspective on cost vs impact. This is starting a conversation that needs to happen, the effort and forethought put into this to get people thinking is arguably more important than the initial results in my opinion. I’ve been taking your joining videos into consideration on every design I have since watching them. I don’t have a FLSUN but I do have an A1m and X1C. Once I get my vented enclosure finished and heat exchanger for thermal management indoors, this is the next thing I want to look at. Watching bridging in real time between stock and BQ shrouds on the X1C was eye opening. The accessory fan cooling the plate would blow the filament together on subsequent passes and cause poor bridging results after 40mm. Then the fan speed and pressure on the extruded filament needed to be targeted enough to not push the cooling filament into the adjacent bridging on initial passes while allowing for cooling. The filament would sag when extruded then tighten up while cooling. 1/2 or more of this equation seems to be slicer parameters, there is definitely a hardware limitation here though. I would suggest also focusing on the actual tool path and runs in real time and not just final results. It paints a better picture of what is going on and has been far more useful for me in tuning.

[@henrivanderriet3895]

Have you tried to visualize with a line laser? Like the ones used to project level lines on a wall.

[@JohnDoe-fk6id]

Came down here to say exactly this. The flashlight helped, but the line laser will isolate "slices" of the flowfield.

[@Cornerstone_Creative]

Was about to recommend the same thing. I’ve used the green ones for airflow test and it works great to see a slice of the airflow

[@NeedItMakeIt]

I have one, I'll give it a try to see what happens. What I can do is take a side panel off so that I can mount the laser in the right position and then still shoot in with the camera from the front, great idea!

[@NeedItMakeIt]

Thanks for that, it's a great idea, I'll give it a try.

[@dimyouprenig]

You can achieve a similar result by restricting your flashlight to a narrow beam with some "curtains". Will give you a way to control "depth" of those slices from a few mm to a few cm. Should also work in combo with laser… some Alien (first movie) VFX mode :)

[@kylek29]

It might be cool to see if you can rig up a Schlieren Imaging setup. Michael Rechtin just happened to do a video on a quick/cheap setup he did to capture some really cool airwave shots. kzbin.info/www/bejne/p6vKg6yfgZutn5Y en.wikipedia.org/wiki/Schlieren_photography

[@NeedItMakeIt]

This would be incredible, I'd love to try it in a future video. I'll check out your link!

[@ThePhilbox]

Cool!

[@r3dzero]

Very good work, it is very useful for me because I'm designing a 3D printer and I will keep it in mind, thanks

[@romeolz]

I wanna see how that will go, subbed

[@stefanNT_1008]

nice work!

[@NeedItMakeIt]

Thanks for that! It wasn't quite as definitive as I had hoped, but it's at least a start.

[@stefanNT_1008]

@@NeedItMakeIt to be honest, this might be the best visual representation of 3d printers cooling fan. I am stoked about the series!

[@Flame0167]

@NeedItMakeIt, have you thought of a ring light attached to the print head facing towards build plate?

[@ManjaroBlack]

This is great testing. One thing about the CPAP, the one I use has external ribbing, but the inside is smooth. It seems like the one you have has internal ribbing? In my testing with the clear tubing on a printer it doesn’t work well. It buckles and doesn’t move well and creates lots of issues.

[@NeedItMakeIt]

Thanks, I hope that in the next videos we'll get even more clear information. I was thinking to move to silicone tubing with a 5/8" ID, it would be just slightly longer than it needs to be, about 8" shorter than the current hose. The hose that came with the printer is ribbed on the outside, but has some corrugations inside too, it might be just a poor quality hose. The ID is too small, that's something pretty easy to address, and I can just cut it to the right length for now.

[@NicksStuff]

I'd have a really hard time drawing any conclusion from these tests. Surely, testing the overhangs, bridges and general print quality is easier (and more representative)

[@NeedItMakeIt]

I always make several videos on any machine I test, so just let me know what you'd like to see specifically and I will make it happen. I have the duct challenge for the next 2 weeks probably, possible 3 and then I can jump back to this printer. I agree with you, I should have shown more standard tests, I just have a hard time printing parts that can't be used for something.

[@NicksStuff]

​@@NeedItMakeIt I understand you not wanting to waste material (we see that on 99.9% of the 3D printing channels already). You could make the ducts easily swappable (like with the use of magnets) and start a long *useful* print with a big constant overhang and three pauses along the height to test 4 ducts

[@alexbogdan5402]

I am curious to see how the HeroMe and EVA ducts behave since these are considered to be the best designs for part cooling. I know its highly unlikely we'll see that since the come as part of a hotend assembly. Regarding the losses in the tube, I don't think it would matter that much since the fan, imo, is already way overpowere for our needs. Plus i think Biqu already factored that in when they speced the fan. As for the Hydra duct, I think some internal channels that split tge airflow and drive it toward each duct might help. But i think it would be necesarry to elongate the inlet of the duct a little and try to make tge paths as tangent as possible. Too bad i don't have MS paint as it would be easier to explain with the help of a drawing

[@engineer1692]

So the problem I see with this testing is that there is no part under the print head. I feel like there should be a simple representative part, like a simple block shape that can be rotated around

[@מיכאלקשי]

interesting!

[@kenniesdead]

can you raise the viscosity of the sparkle liquid so it doesn't splash as much but might still show the effect of the air streams

[@GamingWithURO]

Wonder how using a remote fan source with a light flexible hose would actually work IRL situations. Obviously packaging would be an issue. 🤔🤔🤔

[@RayLenses]

You're becoming my favorite channel, really good quality content, keep it coming

[@802Garage]

Wow the smoke tests are very revealing! They also leave a lot of questions, but still provide a bunch of info. Very interesting the Medusa creates the kind of vortex we think we want to see. Seems to do well actually interacting with the part as well. I'm surprised how even it was given the different tube lengths and all. The shots where you were holding the ducts also showed good info. This definitely revealed the inadequacy of the stock duct. Lots of good insights!

[@JohnDoe-fk6id]

You might want to replace the sparkles with mica powder. It's often used for flow visualization in water tunnels

[@NeedItMakeIt]

I'll have a look right now! My cheap sparkles were sinking and not well distributed, I would have never thought of using mica powder, that's really cool.

[@JohnDoe-fk6id]

@@NeedItMakeIt Glad to help! You're doing great work, and I can't wait to see what comes next!

[@massimo2k1le]

ohh yeah, rheoscopic fluids are so mesmerizing and satisfying to watch ❤

[@jesuiscool7]

Just discovered yesterday your channel with the past video presenting your medusa Fan duct and the work around it. I'm really thrilled to see someone taking the time to do all those tests as detailed as possible. I Also just discovered at the start of this video the "Panda Jet Cooling Fan Duct for Bambu Lab X1" which I will be soon enough be buying :) ! I'm looking forward to your videos when I see the nice quality on technical topics you provide :) !

[@UNVME]

Another question for your testing. Is higher pressure or higher volume better for part cooling? Example, small duct opening with high pressure air that could possibly disrupt the extrusion. Or a bigger duct opening that is flowing more but "softer" air.

[@SquintyGears]

Very cool work on visualisation. Have you considered schlieren imaging too? You get the fog visuals without the mess.

[@HO-cj3ut]

MEDUSA There is a design problem: the incoming air volume slows down as it progresses through the same channel (fluid mechanics). I would help with the design, but I'm a bit busy. Solution: Narrow the air hole along the air channel; by doing this, you prevent the fast-moving air particles in a wider air area from hitting the walls and slowing down. This continues until the final air outlet. The second improvement is the obstacle you mentioned at the air channel entrance. For the third improvement, there is a design flaw: the air comes from a single channel, but in the longest branches, the airflow rate will decrease and slow down; while in the shorter branches, the airflow rate will be higher. You can observe this by aligning a weaker laser at each air channel in a mist test, and you will see that some air channels work less efficiently by reducing the mist. My guess is that the front two branches will be the weakest.

[@drkzilla]

Perhspd you could heat up a thermo coupke and test how long it takes to cool down? Then youbcsn have an empirical measurment with temperature?

[@ajbent1]

I am a little curious what it would be like to pump water out of the fan nozzles and if it would help visualize the potential vortex interactions. Say pumping colored water or water with "sparkles" into the nozzle while it was submerged in water. I have no idea if testing it in water would be useful for characterizing its use with air, but it just seems interesting to try.

[@dave8939]

Try a Schlieren optics setup. Less mess and more detail airflow

[@gpdewitt]

If you have access to an infrared camera - some are relatively inexpensive phone attachments - you might consider testing actual cooling. Perhaps use a metal plate heated to a particular temp, similar to extruded plastic temps. Plate would, of course, have to be the same temp for each test, and ambient the same. You would likely be able to see the cooling pattern on the plate.

[@aaamott]

A line laser might be easier to record and see flow. Especially if you attach it to a rail and move it back to front facing up in place of the flashlight.

[@MsMagnus123]

I think that for a less messy fog test, you could use dry ice in water in the box

[@NeedItMakeIt]

I'll have to try to get my hands on some to give it a try. Using the fog for one test isn't a big deal, but many isn't going to be good for the printer. Your idea might be better way to go for future tests.

[@wekker090]

De medusa left front nozzle melted during test with PA12. I guess it needs some amount of air to keep cool.

[@Haunter1982]

Well, I appreciate the work you put in this. But what is almost forgotten all time in this tests. It only shows while static. In real printing situation the nozzle moves around in fast speeds. So you will get different results even when you change the orientation on your bed. For your CPAP Cooling it is only on the output side of the duct. But think about printers with headmounted fans. Just think about how much more air will get into the inlet of the fan when the head moves "towards" the air, or how much less air if the head moves in the opposite direction... And the next thing is, you do not want to cool down the nozzle or the filament directly beyond the nozzle. But the layer the filament touches. And you dont want to cool only as much as needed to get the material where you put the next layer on, into a temperature where it is stable enogh to carry the next layer but hot enough to melt into the new material... So in my opinion not the most directed is the best but the one which makes the best of all. Big enough to get a good flow even with throttled air flow, small enough to get the air close enogh to the nozzle area and the opening a little bigger on the underside to direct the airstream also down. I think that is also why the oem duct has this additional openings it allows also a little cooling of the larger areas when printing faster.

[@imst4722]

Have you seen the VaLvNaToR duct (thingiverse)? Also some vids from PIRACER VELOCIRAPTOR on trying different ducts/valves for cpap

[@TS_Mind_Swept]

I wonder what a larger version of the fog test would look like 🤔

[@michaelschecker2716]

Please post the link to the fan (kit)

[@suivzmoi]

where are the stls for the test prints?

[@75keg75]

You should look at this for the prusa xl nextruder nozzle. That blows from one side that creates issues with part cooling. The part down stream of the nozzle when parts build up is blocked and parts don’t look quite so good. The fan also seems to cause more wispy dangleberrys that build up over time causing blobs to farm . Couple of attempts to do alternatives on printables but not great options atm I tried to use simscale on one idea but the regions it was testing weren’t easily selected (need more break lines to define surfaces) so Input and outputs weren’t great.

[@NeedItMakeIt]

I looked at that one 2 weeks ago and I couldn't figure it out, why would they only have air coming from one side. My only thought was that they figured it'd be used minimally because it's meant more for engineering plastics. I agree that it needs some more development and when we're done all of our testing I think we're going to have a way better understanding and we'll have some ideas that we can adapt to use for any printer. I've tried Simscale 2x now and I can't figure it out yet, I haven't been able to figure out the region either, the video from Teaching tech shows a different version and it doesn't seem to work the same way anymore. It needs a revisit!

[@AlexServirog]

If you flick laser across the smoke it highlights the slice of the air volume. Try spinning the laser pointer with a motor. Or find laser module that has optics that acomplishes the same

[@AlexServirog]

Ah, everyone suggests line lasers alredy =)

[@mobiobione]

Sweet testing. I wonder if there's anything to be gained with thermal video watching while printing or moving around an empty heated bed.

[@NeedItMakeIt]

I think it's worth a try, I love to try Schlieren imaging to see what it can bring to the table as well. In the end the best way to know is to test each duct design under extreme conditions. It's also good to be able to explain it so we can learn a bit an design even better options from there.

[@JT40_]

So cool, love the fanducts they have a cool sci-fi biomechanical look!

[@NeedItMakeIt]

Thanks! I thought it would be great to do a minimalist approach and add only what needs to be added to keep the weight down.

[@CrazyMonkeyCM32]

Really cool, love your videos. A line laser would be good to visualize the flow in 3d though :)

[@NeedItMakeIt]

It's a great idea, I thought about using my laser level, but I couldn't figure out how to fit it into my printer, what I can do is take the side panel off or test outside of the printer instead. I'll see what I can do to rig something up!

[@ptigad]

First of all, thank you so much for putting in the incredible amount of time and effort in doing these duct tests, it's a truly valuable, selfless contribution! There are two things that you might want to consider including in your duct tests related to pressure and airflow. I think it might be useful if you were to use a manometer to measure the pressure difference between the input and output of the duct (might be a bit tricky consolidating the outputs, perhaps a jig or something that encloses the duct with a common-dimension output?). The other would be actual airflow (anemometer) measurements of the raw input (from your fan/cpap blower) and the final output from each duct (again, maybe a jig or container that encloses the duct and provides a common-dimension output?) In any case, thanks again for this type of content!

[@JohnDoe-fk6id]

output pressure would be atmospheric pressure (unless you meant the pressure just before the outlet), so you really only need a static pressure sensor in the CPAP hose, to get the pressure drop across the duct. Adding airflow (anemometer, hot-wire AFM, or other meter style) to that static pressure drop would give you a much more complete understanding of the "efficiency" of the ductwork. No need to have an airflow meter on the outlet. Unless the system is leaking, mass flow in MUST equal mass flow out, so just measuring flow on the inlet would be enough.

[@ptigad]

@@JohnDoe-fk6id Thanks much for this. I had a feeling I was missing something after I clicked the reply button, lol. You're spot on.

[@nathansantos.n8]

is it even possible to promote better laminar flow of air out of the nozzles to really fine tune where the air is going to?

[@NeedItMakeIt]

I've seen some ideas for air compressor nozzles which could be directly applied to this. The issue of what you do with the warm air is still a problem, with this type of fan, it's pressurizing the chamber, so the air is being pushed out of any crack that it can, with a standard blower fan, that's not the case. I'd like to find out if what we do with this CPAP fan will also work with a traditional blower fan too.

[@notsurt]

Has anyone done a part cooling fan that rotates around the hotend so it's always optimally placed for overhangs?

[@ErtsenPlayGames]

What if u use ICE to test how well it "cool" (melt it in case of ice) could also be pretty "cool" 😆 test or use piece of aluminium/copper rod and square piece (to check difference in case of different print shapes etc) maybe like 10x10x let's say 50mm with insulated first 40mm , only 10mm stick out and can be exposed heat it up to any temp u want (around 100*C should be easiest - throw it into boiling water) and then try to cool it for some time measuring temp

[@NeedItMakeIt]

I have some equipment on the way that is pretty close to your idea. I will have a demo coming in about a week to see how well it does, but I can certainly also try your idea exactly, I like to use things from around the house that everyone can do themselves as well! I wonder if I can heat up a slab of plastic and place it in the printer and measure how long it takes to cool to a desired temperature as well.

[@ErtsenPlayGames]

@@NeedItMakeIt could work with plastic but harder to measure the temp. Plastic insulate pretty well so its harder to measure the temp , alu/ copper/ bronze will transfer it so should be easier to measure BUT....maybe hollow 3d print, filled with water and thermistor inside 🤔 Or for testing how well it cool down single layer use 1mm thick flat bar exposed only for like 1mm (or less) above slot in a 3d print holder (that will act like rest of the print around that "layer" to simulate how well it can cool single layer🤔🤔🤔🤔🤔 I was doing my own test years ago by changing all the time fan duct shapes sizes etc....ended up with 5025 blow fan on the side with single duct (2/3 of a circle) and can use mostly 2-5% when printing at 80mms (0.6 and above nozzle sizes+ thick layers (0.4+)) or its cooling way to fast for what i print (petg , pctg ,abs all in chamber 50+*C (with max over 100 so can set it up for high temp more cooling but its not as simple sometimes) 😅

[@mikeydk]

If you want to try the fog testing again, but without all the mess, you can put dry-ice in water, the haze from that won't form drops like glycol does.

[@NeedItMakeIt]

I'm open to that for sure. I'd just need to find out where I can find a supplier. I'm a little worried about how long I'd be able to run these fog tests before I ruin something.

[@mikeydk]

@@NeedItMakeIt using dry-ice to make the fog should be a lot safer for the equipment, but it isn't as convenient as just heating the smoke machine up :)

[@-SeanyBoy-]

THIS IS 1 OF THE ONLY SERIES ON KZbin I ACTUALLY LOOK FOWARD TO, KEEP UP THE GREAT WORK!

[@NeedItMakeIt]

Nice! I will have more coming and I hope we can do even better on the next to clearly show what's happening and then we'll have the testing of new duct designs to see who can come up with the best designs. I'd really cool and hasn't been explored too much yet, it should be super interesting to see where this goes.

[@tbkowens]

you probably would have had a better result just using a thermal imaging camera...

[@NeedItMakeIt]

That's coming! I'm open to any device to test. I really wanted to try to see the air movement in this test, but the thermal camera is also going to be great to have to use in combination.

[@tbkowens]

@@NeedItMakeIt I've been trying to get a hold of you. I've been doing a bunch of testing on the K1 series printer and designing ducts. I might be able to give you some insight. I'll join your patron and hopefully together we can crack the code!

[@didja101]

I'm curious about the air vortex concept. Isn't a vortex an area of low(er) pressure? Don't we want higher air volume/pressure around the nozzle, not less? Imagine a whirlpool of water. If you make it fast enough you end up with a void at the vortex. Maybe the venturi effect would pull air into the vortex, but I am not sure.

[@NeedItMakeIt]

I'm no vortex specialist that's for sure, but I have watched a few movies, so.... :) I don't think the vortex is the best approach overall, they're just an idea that I had, what I did was try to offset it so that we'd have some turbulence in the center and the vortex around the outside more or less, it's a little tough to see, so I'll have to do more testing, but the results were pretty good. The vortex idea would allow warmed air to escape fairly easily while also not creating too much downward force on the filament as it's extruded so we have better overhangs.

[@didja101]

@@NeedItMakeIt Totally get your reasoning. Just thinking that the dynamics of air cooling are a lot more complex than we probably think. Or maybe at this temperature/volume more is just more. Keep up the great work!

[@lamarcdesign]

Currently working on a fanduct for the neptune 4 and i used cheapo vfx smoke sim to iterate on my design. Offset duals sounded nice but the unequal distribution of air left and right makes it quite unpredictable. The regular dual seem to work best. Ideally i would have added a smaller 3rd center one to push the air slightly backwards out of the printarea. What greatly helped was opening the ducts towards the bottom to let air escape towards the bottom. This created a much larger patch of high flow air around a solid surface which in return should(untested) improve overhang quality quite a bit

[@NeedItMakeIt]

That's great info thanks for that! The duals seem to crank out a huge amount of air. Someone mentioned that it's best to consider air as something "sticky" so smooth ducts and less distance is better and keeping the ducts as large as possible also helps. I'd love if you'd join our challenge, I have a link at the end of the video to the challenge itself, there will be real prizes as well.

[@lamarcdesign]

@@NeedItMakeIt I saw another video by some CFD guy he said you can reduce the opening to increase airspeed but the reduction rate of the inner diameter can only be max 11% per given distance. Also keep it short yes as air wants to stick to the walls reducing the effective inner diameter. Air is pretty difficult as it always does the opposite of what one expects. I will see if I can find time as im currently on vacation

[@realgoose]

Glitter… the herpes of crafts

[@NeedItMakeIt]

I think I'll be moving on up to Mica powder, that is going to be so awesome to visualize

[@punkreeperful]

Im curious how the stock cooling fans react using this method, and see ways how you can improve it

[@NeedItMakeIt]

We'll be looking into that too, the stock ducts never seem to do too well, maybe they're just not moving enough air, or perhaps it's that they're pulling warmed air in from the chamber so it can't cool as quickly. It is certainly worth a closer look.

[@punkreeperful]

@@NeedItMakeIt im looking forward to it. I wanna find out if companies are skimping on cooling or if their stock cooling is good enough

[@venugopals9680]

It's great research and very helpful for the 3D printer community. Thank you very much for these kinds of experiments. Awesome job.

[@NeedItMakeIt]

Thanks for that I really appreciate it! I wanted to get a bit more definitive info from this, but it's just the start and I think we made a bit of progress. I think if we can get some more people interested in the competition, we'll see some really unique and effective designs.

[@SpoolTitan]

Air doesn’t like turns

[@ryanmisek]

Great job breaking this down. I appreciate the approach you take throughout each of your tests.

[@NeedItMakeIt]

Thanks for that ! I had no idea just how much trouble this fog would be when I started, everything is still working on the printer luckily, I just need to make sure I keep it clean. I'll refine the tests a bit and see what we can come up with to do even better next time.

[@minty_lint]

Great job adding the laser. really helps to see what's going on.

[@NeedItMakeIt]

Thanks, the laser looks so cool! I will try to revisit this and really narrow down some testing for a bit more clarity and I'll work on the lighting as well. I think the water test was helpful as well, but the sparkles weren't ideal, someone mentioned mica powder, so I'll order some and try it out.

[@FlashEF]

Take a look at the how Major Hardware is doing his fan tests with smoke. He moved to a single trail of opaque smoke rather than making an entire intake smoky. With a single smoke trail you can watch flow in different sections sepretly and really study what's happening.

[@NeedItMakeIt]

I had a look at his videos, I just didn't look at how he was able to create that single line. Testing within these ducts is quite a bit more difficult than I was expecting to get really clear info. I'll try it and see how much of a difference it makes, thanks for that!

[@FlashEF]

​@@NeedItMakeIt I think the key is less, but more opaque smoke dispensed from a small nozzle, like a Ø3 stainless tube. Those tests are hard, my instinct would be to try some CFD software but that's easier said than done. I've done extensive research for something affordable for my work, and the conclusion was that it's either OpenFoam with a steep learning curve or something ungodly expensive but fun like Ansys Discovery Live (so cool!). But maybe someone knows a better option, simulations can give you fantastic insight on what to look for with practical testing.

[@SuborbitalSciences]

I’m loving where this duct design series is going! Nice work!

[@SuborbitalSciences]

One cool idea would be a retractable mechanism that deploys once the printer is at a certain z height to cool the print at an extreme angle.

[@NeedItMakeIt]

Nice, thanks for the support! I'm hoping we can get to a point with these that we can make a big difference in 3D printer cooling. I need to refine the test a bit more and get more clear info, but we're getting there.

[@Kentrilek]

my knowledge about 3d printing is limited so I dont understand what do you want to achive. As far as I know you need to keep your nozzle at constant temperature so no air flow at a nozzle. Do you know does your material like to be coled rapidly? what about skrinking and tensions? what about changing inner structure after rapid cooling? will it be harder but more britle? if you want to use it for bridging why you want to apply so much pressure at hottest material right under the nozzle? what about sagging because of pressure? shouldnt you just adjust material flow and speed to make first layer of bridge better? what is the overall point of air flow in 3d printers? if you want to just take away heat shouldnt you adjust your ducts to make vortex to pointing a little bit wider around the nozzle and maybe pointing up?

[@NeedItMakeIt]

You've pretty much got everything there. For PLA printing it needs lots of cooling quickly. PETG seems to be highly affected by too much cooling, it becomes brittle and will fracture. ABS will shrink and deform and cause all kinds of trouble. Most people use PLA for 3D Printing at the moment, I don't use it much, but when I do, it is a pleasure to print with! As far as the goal, we're looking to find the best overall duct to use for high speed printers for now and for future, currently they are not engineered well enough to keep up with the speeds of the printer. We'd like to be able to print faster, but cooling becomes a problem on smaller parts which don't have enough time to cool between layers and especially on overhangs, so instead we have to slow the prints down. As printers become faster and faster I think it would be wise to get ahead of it and have some solutions ready. I can't say I have a great understanding of what products the best results yet, I am working on more testing to try and make it as simple as possible to understand. Initially it seemed a matter of getting the most cool air to pass by the filament as it was extruding, but as you put it, we also need to consider how much force there is from that air, especially on bridges. Can you explain your idea of the pointing up, we can't be lower than the nozzle, but maybe there is a way to do this?

[@Kentrilek]

@@NeedItMakeIt I had an idea to make you octopus ducts (but maybe there is to many points of air flow? maybe just 3 would be enough?) parallel to a printing surface (0.5-1mm higher than the tip of the nozzel?) and at the very end make it 3-10 degrees pointing upwards. Air flow should be as close to the nozzle as it can be without hitting it as we do not want to cool it down to much. this type of air flow should make a little underpressure below the tips of a nozzle so heat from layers already printed should be sucked up therefor no additional heating from hot air pushed from your nozzle downwards. This is theory. and in practics you have whole printer head above the nozzle which makes this task a lot more compliacated. Maybe you should try to make ducts around the nozzle and up further away from the print with wholes in ducts close to the nozzle so air flow inside will suck hot air from around the nozzle? (ejector pumps - making underpressure with air flow). English is not my main language so sorry for mistakes :)

[@SianaGearz]

There's no clear recipe on how to do it best! It is considered vaguely ideal to freeze the material into shape as it exits the nozzle. Sure you're introducing extra tension into the material, but you get a lot better geometric alignment and more geometric freedom. If you want less stress then sure you can do that you can always reduce the amount of cooling by modulating the fan power, but you can't increase the amount of cooling beyond what the system can deliver :D Opposite of what NeedItMakeIt says many people blast their ABS and related styrene polymers pretty hard and are getting good outcome with that. But when you do that, you also can't have cold air intake in combination with high airflow, or you'll drop the chamber temperature, which is bad for layer to layer welding. Unless you perhaps run the print speed and the temperature setpoint way up! There is no single recipe to success. Nozzle is "constant temperature" anyway, i mean yes blasting it with air draws away a good amount of temperature, but if you run more cooling, you can just choose your temperature setpoint a little higher. It's even debatable whether you want the nozzle all too hot, it's a possibility that you need the meltzone temperature hotter in order to quickly saturate the whole melt with heat, but perhaps you want the melt bead as it comes out already starting to cool down to make it solidify quickly. Some very successful and eerily quick printers have used stainless steel airbrush nozzles in the past which actually precool the bead a lot, because their thermal conductivity from the hotend is low and their ambient cooling is very high. PETG should be nozzle-cooled like that a little, just a little, but not too much. One qiute successful fast-printing cooling system is Berd Air, which is a tiny metal air nozzle set which points straight under the extruder nozzle, and is supplied at very low air volume and high pressure from a vacuum pump. But others have thrown massive air all over the print and that's worked for them :D I think ideally you want to cool the bead as it comes out as quickly as possible to Tg, and then stop cooling it, while simultaneously not letting it deform from air blasting onto it. But these are all very conflicting goals.

[@Kentrilek]

@@SianaGearz so basicly we should start from learning as much as we can about material we will use. And as I dont know much about any of them let assume that PLA needs as rapid cooling as we can get. Solution? do not apply high pressure with fancy fan ducts and more powerful fans you just need to suck cold air from your fridge :D or add some powerfull exhaust fan not a simple blower :P

[@SianaGearz]

@@Kentrilek I don't know that we know which fundamental properties the behaviour of each material is down to! At least i haven't heard or seen it described anywhere. Like, PETG has higher thermal conductivity and lower specific heat capacity than PLA and Styrenes, then why the heck is it so difficult to heat all the way through and get flowing? And why when it's already flowing, is it impossible to stop, just keeps going and drooling all over the place? What is going on there? Shouldn't it be the other way around? So i think until we understand the molecular mechanics/physics of 3D printing, we're going to be running in circles with surprise melt behaviour. And if we do someday understand it, that opens up completely new control opportunities, because if the slicer can accurately predict the melt behaviour, it can also compensate for it.

[@KittenRaee]

"It's hard to tell" is a motto of this episode :P

[@IronMan-yg4qw]

using something like simscale to model the airflow would be more productive.

[@NeedItMakeIt]

I've tried it several times, but it has changed and I haven't found a good walkthrough yet. Do you have some tips for it?

[@IronMan-yg4qw]

@@NeedItMakeIt sry i dont use it for airflow. but i want to. :[

[@IronMan-yg4qw]

@@NeedItMakeIt kzbin.info/www/bejne/Z5bMfamBZdunbKs

[@IronMan-yg4qw]

@@NeedItMakeIt kzbin.info/www/bejne/Z5bMfamBZdunbKs

[@Malewifee]

25 SEC FIRST!!