[Cooling] Candlelight Vigil, please pay your respects.  

Re: Candlelight Vigil, please pay your respects.

what shroud have you the stl

Re: Candlelight Vigil, please pay your respects.

what shroud have you the stl

Giving this one a try for a bit: https://www.thingiverse.com/thing:2720541 - if you print it, use supports and set the support degree angle to 2. It'll just support the straight bridged areas and leave the other stuff alone.

Re: Candlelight Vigil, please pay your respects.

Yup, this is one of first prints once I have mine up and running!

Re: Candlelight Vigil, please pay your respects.

Giving this one a try for a bit: https://www.thingiverse.com/thing:2720541 - if you print it, use supports and set the support degree angle to 2. It'll just support the straight bridged areas and leave the other stuff alone.

I'm just curious. Why did you choose that one over, say, this one? https://www.thingiverse.com/thing:2740613

I actually printed the one I linked above, and I couldn't get the "low profile" cable adapter thing to go on right. (that's actually how I broke my LED off the bed)

It actually has some really interesting duct-work inside of it. I was super impressed with the "design" concept of the ducting. I plan on going back and trying again some time, but for now it's on hold, as the standard one is "enough" for me. (for now) I'm likely going to be re-printing the entire X axis in a few weeks, and will likely try again then. (I can't get a 90a flex filament to print with any degree of reliability, it just LOVES to wrap around my bondtech gears)

Re: Candlelight Vigil, please pay your respects.

I'm just curious. Why did you choose that one over, say, this one? https://www.thingiverse.com/thing:2740613

I liked this one because the air path is very short, and a more equal opportunity for air to blow out in a balanced and predictable way. Consider the following:

Static Pressure (SP)
Static Pressure is the resistance to airflow (friction) caused by the air moving through a pipe, duct, hose, filter, hood slots, air control dampers or louvers.

In the design you linked, the path the air has to travel is longer and goes through more bends. Based on the above, that extra resistance will impede airflow. Also with that design, even though there are routing channels inside to help balance things, some channels have a much longer path and more bends than others. I'm sure with enough tweaking you could balance it out on all sides, but it seems like you'd end up dumping more energy to get this effect.

I can see the usefulness in the design, because it's incredibly hard to see the nozzle as it lays down that first layer; unfortunately, with the stock nozzle or even the nozzle I am trying, the blower fan just doesn't seem to push the required air. I imagine it would be even less with that additional static pressure fighting against it. 🙂

Now, if the fan were upgraded, that nozzle might be a completely different story and quite nice. 😀

Re: Candlelight Vigil, please pay your respects.

I agree on that totally. My main thought about the one you linked, is it has no ducting to force the air around to the "other side".

The air will follow the path of least resistance.
On your model, it appears the openings are larger than even on the original.

Does a higher volume of low pressure air cool better than a smaller stream of high pressure?

Eg: do you open your mouth wide as if to fog a window, and empty your whole lungs quickly, or close your lips and blow a fine stream of air, for much longer to cool the hot tea in a spoon? Is more, or less air better for cooling the spoon?

Don't forget the cooling fan for prints is a pressure fan. Those fans perform better with pressure than most people give credit.

PS: that one I linked has good airflow volume. I can blow as hard as I can through it without feeling (relevant) resistance.

Re: Candlelight Vigil, please pay your respects.

I tried one of the earlier JLTX Cobra designs, and found it acught on the bed cable clamp ant steel plate locating pins during calibration.

I don't know if that has been fixed

regards Joan

Re: Candlelight Vigil, please pay your respects.

No Joan, the problem is still there. That is a great cooler but suffers of the problem of touching/scraping the bed connector and/or the back alignement pins. Jlts provides also a new low profile bed connector cover but in my case is not enough and the cooler scrapes the connector and does not complete the xyz calibration. That cooler needs a rework to lift up at least 3-4 mm the back side to avoid the issue.
I've also tried the codiac2600 cooler (#13) but in my comparative test there is no noticeable difference in cooling quality with the stock one. Probably is better in the drop down issue, but on the cooling side for me works the same as the stock.

Re: Candlelight Vigil, please pay your respects.

I've also tried the codiac2600 cooler (#13) but in my comparative test there is no noticeable difference in cooling quality with the stock one. Probably is better in the drop down issue, but on the cooling side for me works the same as the stock.

So far I have slightly better cooling with it than stock, but not a complete fix of the benchy horizontal line issue.

I agree on that totally. My main thought about the one you linked, is it has no ducting to force the air around to the "other side".

The air will follow the path of least resistance.
On your model, it appears the openings are larger than even on the original.

Does a higher volume of low pressure air cool better than a smaller stream of high pressure?

Eg: do you open your mouth wide as if to fog a window, and empty your whole lungs quickly, or close your lips and blow a fine stream of air, for much longer to cool the hot tea in a spoon? Is more, or less air better for cooling the spoon?

Don't forget the cooling fan for prints is a pressure fan. Those fans perform better with pressure than most people give credit.

Yeah wondering about that as well, I am wondering about plugging the front holes altogether and force air out the sides only:

Re: [Cooling] Candlelight Vigil, please pay your respects.

Trying a benchy after this little plug job, see how things fare. Wondering if the side holes are enough to hit all sides of the nozzle.

Re: [Cooling] Candlelight Vigil, please pay your respects.

Trying a benchy after this little plug job, see how things fare. Wondering if the side holes are enough to hit all sides of the nozzle.

I am eagerly awaiting your test result report. Airflow and static pressure is something easily overlooked or forgotten. Even when air pressure and flow is considered during design, often real world testing is the best evidence.

Re: [Cooling] Candlelight Vigil, please pay your respects.

Trying a benchy after this little plug job, see how things fare. Wondering if the side holes are enough to hit all sides of the nozzle.

I am eagerly awaiting your test result report. Airflow and static pressure is something easily overlooked or forgotten. Even when air pressure and flow is considered during design, often real world testing is the best evidence.

An ever so slight improvement over unplugged, really had to look hard for it. Was the most visible in the bridging above the the window at the front of the boat (unplugged had very very very slight sag, plugged was straight as an arrow). After this test, I feel something like this: https://www.thingiverse.com/thing:2088006 would be the direction to be headed (very focused, hits all sides of the nozzle); however, Prusa's location of the blower fan is way too low. The blower pretty much has to blow straight into a wall. Jltx's design tried to compensate for this by turning the blower at an angle, but this may take some trial and error to determine how to get equal flow on both sides and increased the air travel distance significantly more than say... mounting the fan a half inch higher.

- here's the benchy I ran with the plug test, pretty sweet little piece showing off LA, stepper linearity correction etc; however towards the end of the video I lift it up towards the light so you can see the horizontal line is still there. I may be fighting a losing battle here, maybe those top layers are enough to pull the perimeters inward after the fact? Hard to say, thoughts are appreciated.

Edit: Trying a 5C drop on the Generic PLA profile, see how that treats us.

Re: [Cooling] Candlelight Vigil, please pay your respects.

An ever so slight improvement over unplugged

I've been having really good luck with the shorter version of this one so far: https://www.thingiverse.com/thing:2748058

Noticeable improvement when I printed a temp/overhang tower on each one.

Re: Candlelight Vigil, please pay your respects.

Giving this one a try for a bit: https://www.thingiverse.com/thing:2720541 - if you print it, use supports and set the support degree angle to 2. It'll just support the straight bridged areas and leave the other stuff alone.

I'm just curious. Why did you choose that one over, say, this one? https://www.thingiverse.com/thing:2740613

I actually printed the one I linked above, and I couldn't get the "low profile" cable adapter thing to go on right. (that's actually how I broke my LED off the bed)

It actually has some really interesting duct-work inside of it. I was super impressed with the "design" concept of the ducting. I plan on going back and trying again some time, but for now it's on hold, as the standard one is "enough" for me. (for now) I'm likely going to be re-printing the entire X axis in a few weeks, and will likely try again then. (I can't get a 90a flex filament to print with any degree of reliability, it just LOVES to wrap around my bondtech gears)

Just 4 fun decided to print the https://www.thingiverse.com/thing:2740613 . It has some pretty intricate air directors and hard to print looking bridges that intrigued me. I also just happen to have a 'testo 405i thermal-anemometer that is small enough to stick in the airflow if the fan and cooler are swung away from the heaterblock-nozzle.

Observations:

1. Overall flow, if the PRUSA flows 7 units of air the JLTX flows 6. The bare fan with no cooler flows about 8.5. These measurements were taken at the fan intake of each.
2. On a different scale and looking at velocity, not volume, the 8 flow channels, left to right the PRUSA would be something like 1 2 0 7 7 0 2 1, almost all the flow is out the front middle, with the adjacent middle doing nothing and the ends little.
3. The JLTX has 10 channels, the two in front which blow toward the back, even though one is way at the end of the flow channel on the right do about a 7. All the rest of the channels do between 3 and 5 even the ones blowing forward.

The JLTX flows less air but at higher velocity and from all sides. Good or bad, I don't know.

I didn't install the JLTX because I printed it with PLA and it looks like I would need to mess with my spiral wrapped wiring to get enough fan wire and move the heater and tc wire. Maybe sometime later.

Re: [Cooling] Candlelight Vigil, please pay your respects.

In my testing the jltx cooler is the best in term of uniformity of flux. The only problem for me is the too long (and low) back side that scratches on the bed cover. It is invaluable the front free clearance.

Re: Candlelight Vigil, please pay your respects.

Just 4 fun decided to print the https://www.thingiverse.com/thing:2740613 . It has some pretty intricate air directors and hard to print looking bridges that intrigued me. I also just happen to have a 'testo 405i thermal-anemometer that is small enough to stick in the airflow if the fan and cooler are swung away from the heaterblock-nozzle.

Observations:

1. Overall flow, if the PRUSA flows 7 units of air the JLTX flows 6. The bare fan with no cooler flows about 8.5. These measurements were taken at the fan intake of each.
2. On a different scale and looking at velocity, not volume, the 8 flow channels, left to right the PRUSA would be something like 1 2 0 7 7 0 2 1, almost all the flow is out the front middle, with the adjacent middle doing nothing and the ends little.
3. The JLTX has 10 channels, the two in front which blow toward the back, even though one is way at the end of the flow channel on the right do about a 7. All the rest of the channels do between 3 and 5 even the ones blowing forward.

The JLTX flows less air but at higher velocity and from all sides. Good or bad, I don't know.

I didn't install the JLTX because I printed it with PLA and it looks like I would need to mess with my spiral wrapped wiring to get enough fan wire and move the heater and tc wire. Maybe sometime later.

If you have any more time for fun, I have attached the nozzle I am using along with the plug to seal off those front problem holes that are dumping all the air. That's an interesting little tool you have there. 🙂

Re: Candlelight Vigil, please pay your respects.

Giving this one a try for a bit: https://www.thingiverse.com/thing:2720541 - if you print it, use supports and set the support degree angle to 2. It'll just support the straight bridged areas and leave the other stuff alone.

I'm just curious. Why did you choose that one over, say, this one? https://www.thingiverse.com/thing:2740613

I actually printed the one I linked above, and I couldn't get the "low profile" cable adapter thing to go on right. (that's actually how I broke my LED off the bed)

It actually has some really interesting duct-work inside of it. I was super impressed with the "design" concept of the ducting. I plan on going back and trying again some time, but for now it's on hold, as the standard one is "enough" for me. (for now) I'm likely going to be re-printing the entire X axis in a few weeks, and will likely try again then. (I can't get a 90a flex filament to print with any degree of reliability, it just LOVES to wrap around my bondtech gears)

Just 4 fun decided to print the https://www.thingiverse.com/thing:2740613 . It has some pretty intricate air directors and hard to print looking bridges that intrigued me. I also just happen to have a 'testo 405i thermal-anemometer that is small enough to stick in the airflow if the fan and cooler are swung away from the heaterblock-nozzle.

Observations:

1. Overall flow, if the PRUSA flows 7 units of air the JLTX flows 6. The bare fan with no cooler flows about 8.5. These measurements were taken at the fan intake of each.
2. On a different scale and looking at velocity, not volume, the 8 flow channels, left to right the PRUSA would be something like 1 2 0 7 7 0 2 1, almost all the flow is out the front middle, with the adjacent middle doing nothing and the ends little.
3. The JLTX has 10 channels, the two in front which blow toward the back, even though one is way at the end of the flow channel on the right do about a 7. All the rest of the channels do between 3 and 5 even the ones blowing forward.

The JLTX flows less air but at higher velocity and from all sides. Good or bad, I don't know.

I didn't install the JLTX because I printed it with PLA and it looks like I would need to mess with my spiral wrapped wiring to get enough fan wire and move the heater and tc wire. Maybe sometime later.

This is great data. Thanks. I have run some computational fluid dynamics simulations using openFOAM, but just laminar flow. I made some adjustments from that data (still need to post the updated part). I will compare to your data and refine the simulation.

The whole flow problem is tricky. The small 5V blower fan doesn't like much back-pressure. There is very limited volume to work with under the extruder where you want to keep the cross-section area high. I initially tried to match nozzle area to stock, but found the air flow was too low. So I reduced them to increase the nozzle velocity which helped, but increased back-pressure. Tricky balance. I tried a 12V and even a 24V fan and I think they have slightly higher static pressure, but the flow volume feels the same. I don't have proper testing equipment. I'd love to get that anemometer.

I have been using this cooler (all PLA) for a couple months and here's my assessment:

Pros:
nozzle view and garter screw are huge wins for me. 🙂
despite 100% PLA I have had no sagging, but only ~6 hr PETG prints for worst stress so far.
cooling works better for some prints due to air stream from all sides.

Cons:
The PINDA side is definitely compromised and I see cooling artifacts on some prints (so I rotate them to avoid that area if possible)
The overall flow is reduced because there is only so much air coming out of the blower, now distributed more.

So not ideal, better in many cases, worse in some. Still, I am happy with this solution for now and plan to keep using it. Feedback welcome.

Meanwhile, I have completely redesigned the entire extruder, x-carriage (to improve other issues). Now I am porting parts of this design as the cooling solution but have a bit more room to play with.

Re: Candlelight Vigil, please pay your respects.

No Joan, the problem is still there. That is a great cooler but suffers of the problem of touching/scraping the bed connector and/or the back alignement pins. Jlts provides also a new low profile bed connector cover but in my case is not enough and the cooler scrapes the connector and does not complete the xyz calibration. That cooler needs a rework to lift up at least 3-4 mm the back side to avoid the issue.
I've also tried the codiac2600 cooler (#13) but in my comparative test there is no noticeable difference in cooling quality with the stock one. Probably is better in the drop down issue, but on the cooling side for me works the same as the stock.

Sorry to hear that. Feel free to contact me for help. Did you use the latest version (with the clip)? You still need to remove it for a full XYZ calibration (I hate those f'ing pins!) but for all normal printing there is plenty of clearance. I have only done 2 full XYZ calibrations since I got the printer in December so I don't really see that as a big drawback in practice (though I do agree it is annoying).

Re: [Cooling] Candlelight Vigil, please pay your respects.

Does anyone know if the other old design for premium printers with 2 cooling fans, one on each side, and no real ducting. (just a concentrator to direct the air at the nozzle) or the single fan, with the full shroud?

Like, I'm thinking if the air simply hits the nozzle 180 degrees from itself, with a fast air stream, it may as well cover all 360 degrees of coverage, and perform the same/better, as each of the 2 ducts would get ~3x more air than the default one? (I would actually think a 160 degree would be more optimal, as it would encourage the air to flow "past" the nozzle, and not just "collide" at the nozzle, it would still result in a situation where the "front" of the object would be better than the "back", but it would be fairly minimal I would think, I'm unsure if there is a "perfect" solution, without using compressed air, or much bigger fans)