Improved fan shroud / nozzle  

Re: Improved fan shroud / nozzle

I see yours loads standing on end. What is the best orientation for printing?

Re: Improved fan shroud / nozzle

I see yours loads standing on end. What is the best orientation for printing?

Yeah, that's a mess up coming from that I draw my stuff in any arbitrary direction of the coordinate system so thingiverse and slic3r misinterpretes which direction is supposed to be up.
The best direction is with the side that you put the bolt in from facing down onto the build plate. The thingiverse link is active now and it has a picture of the printed orientation. The uploaded file has a few more support studs added than what I printed as some of the overhangs was too unsupported. 🙂

The cooling is pretty efficient now with my intake tract and this duct so I've had to raise the temperature to keep the bonding of the layers good as the part shown on the picture below was printed at 200 degrees and the layers came apart easily.

Re: Improved fan shroud / nozzle

Just an update: after using my intake funnel and duct I'm now able to print this pasta screw (scaled 1200% to a height of 20mm) without having any ugliness at all on the backside which I had with the original duct and no funnel due to insufficient cooling.
Also I've reduced the fan speed from 85% to 50% for when small objects are not being printed. All in all, having 3-point cooling is probably a good mod to do to this printer.

Re: Improved fan shroud / nozzle

Your intake funnel is also known as a "velocity stack"...they are proven to increase air flow efficiency...good on you. I'm going to make both this and the the 3 point cooling duct. Thanks sebastian.J!

Re: Improved fan shroud / nozzle

Your intake funnel is also known as a "velocity stack"...they are proven to increase air flow efficiency...good on you. I'm going to make both this and the the 3 point cooling duct. Thanks sebastian.J!

Yeah I thought that the 90 deg corners that the air from the sides has to do to enter the fan area would be bad so something like this would be bound to increase efficiency.
My textbook on fluid mechanics state that a tube attatched abruptly to a fluid reservoir with sharp edges will have a 12,5 times higher pressure drop than a tube attatched with well rounded edges if the fully developed flow velocity in the tube section is kept the same for both sections. So from that, I designed that velocity stack with inspiration from the automotive and aerospace industry but I haven't had time to do any CFD analyzes on it yet, so I have no idea how much oversized it is. It doesn't weight much if printed with sparse infill though so it's probably minimal what benefits an analysis could do other than possibly saving a bit of printing time.

I think it looks pleasing though so even before I noticed the benefits of the added cooling of the combination, it had added value for me.

Re: Improved fan shroud / nozzle

Your intake funnel is also known as a "velocity stack"...they are proven to increase air flow efficiency...good on you. I'm going to make both this and the the 3 point cooling duct. Thanks sebastian.J!

Yeah I thought that the 90 deg corners that the air from the sides has to do to enter the fan area would be bad so something like this would be bound to increase efficiency.
My textbook on fluid mechanics state that a tube attatched abruptly to a fluid reservoir with sharp edges will have a 12,5 times higher pressure drop than a tube attatched with well rounded edges if the fully developed flow velocity in the tube section is kept the same for both sections. So from that, I designed that velocity stack with inspiration from the automotive and aerospace industry but I haven't had time to do any CFD analyzes on it yet, so I have no idea how much oversized it is. It doesn't weight much if printed with sparse infill though so it's probably minimal what benefits an analysis could do other than possibly saving a bit of printing time.

I think it looks pleasing though so even before I noticed the benefits of the added cooling of the combination, it had added value for me.

Going by https://en.wikipedia.org/wiki/Venturi_effect your cone would be more efficient if it had an exiting angles of 5 degrees. Still, this is a great idea and much appreciated I will definitely give your ideas a try very soon!

Re: Improved fan shroud / nozzle

Your fan nozzle/shroud works great! KUDOS...I need to try the stack next. Thanks for the share.

Re: Improved fan shroud / nozzle

Your fan nozzle/shroud works great! KUDOS...I need to try the stack next. Thanks for the share.

That's great to hear! Did the extra support collumns for the "arms" work as support as intended?
I added them after seeing more sag than expected on my own print, so I'm a bit curious to how it works or if even more collumns should be added. 😀
Also, If you took any pictures of it after printing, could I press you to upload some pictures for me to see?

Re: Improved fan shroud / nozzle

It printed very well...and works greatI I've only tried PLA so far and found that I can run lower hotend temps (very minor stringing)...my Benchy shines like a new penny and the bridging is much improved! Sorry, I didn't take any photos.

Re: Improved fan shroud / nozzle

Funnily, I have a better front view of the nozzle now with your design.

Re: Improved fan shroud / nozzle

I just noticed that the three "arms" are shaped like air foils...cool!

Re: Improved fan shroud / nozzle

I just noticed that the three "arms" are shaped like air foils...cool!

Yeah the three arms that hold the center cone in the middle of the funnel are designed roughly to have similar shape as an air foil. I made them symmetrical though as I couldn't visualise which direction of a cambered air foil would benefit the airstream here and having the wrong way would probably stall the air and decrease the performance.

Re: Improved fan shroud / nozzle

Just an update: after using my intake funnel and duct I'm now able to print this pasta screw (scaled 1200% to a height of 20mm) without having any ugliness at all on the backside which I had with the original duct and no funnel due to insufficient cooling.
Also I've reduced the fan speed from 85% to 50% for when small objects are not being printed. All in all, having 3-point cooling is probably a good mod to do to this printer.

Sebastian.j,

These are very nice mods, thank you for postinging.

Re: Improved fan shroud / nozzle

Just an update: after using my intake funnel and duct I'm now able to print this pasta screw (scaled 1200% to a height of 20mm) without having any ugliness at all on the backside which I had with the original duct and no funnel due to insufficient cooling.
Also I've reduced the fan speed from 85% to 50% for when small objects are not being printed. All in all, having 3-point cooling is probably a good mod to do to this printer.

Sebastian.j,

These are very nice mods, thank you for postinging.

Thanks!
A shout out to PJR though as having the measurements of his fan duct greatly helped making a design that fits the fan and does not touch the heater block.

If you have any pictures of your print of them, it would be awesome to see as I'm thrilled about the attention but still haven't seen any other prints than those I've done myself.

Re: Improved fan shroud / nozzle

I'm having a lot of stringing after installing non-stick nozzle and brake. Even with these I got a PETG jam, but I digress, the issue for nozzle thread is updrafts making all the strings accumulate on the heater block. I'm using my own design that blows on opposite ends, though the focus and cooling is excellent, I neglected up-drafting. Do you guys think a triple nozzle offset to create a axial vortex around the extruder nozzle would work?

Re: Improved fan shroud / nozzle

Made this up today, printing it now to see how it works. seeing as im new to the 3d modeling game im pretty sure its not going to do well, but was a good learning experience.

Re: Improved fan shroud / nozzle

If you have any pictures of your print of them, it would be awesome to see as I'm thrilled about the attention but still haven't seen any other prints than those I've done myself.

Blue PETG...

Re: Improved fan shroud / nozzle

Blue PETG...

Niiiice! Thanks! 😀
Really cool to see!

I'm having a lot of stringing after installing non-stick nozzle and brake. Even with these I got a PETG jam, but I digress, the issue for nozzle thread is updrafts making all the strings accumulate on the heater block. I'm using my own design that blows on opposite ends, though the focus and cooling is excellent, I neglected up-drafting. Do you guys think a triple nozzle offset to create a axial vortex around the extruder nozzle would work?

I'm no sure what the non-stick nozzle is about since searches doesn't really lead me anywhere but regarding creating a vortex with 3 offset air jets, that could actually be a pretty cool concept!
No idea if it would as intended though.

Made this up today, printing it now to see how it works. seeing as im new to the 3d modeling game im pretty sure its not going to do well, but was a good learning experience.

Nice work getting into 3D modeling. 🙂
I have one tip: Add fillets everywhere unless you absolutely have a need for a sharp corner.
Air flow isn't happy with sharp corners so most places, any fillets added will be beneficial without increasing manufacturing time/costs as it would with conventional machining. In fact, fillets will speed up your printing because when the printer approaches a 90deg corner, it decellerates to a full stop at the corner and then accelerates in a new direction. With a fillet, the printer doesn't need to come to a full stop but only to change its direction slightly and thus a higher average velocity can be held.

Re: Improved fan shroud / nozzle

Blue PETG...

Niiiice! Thanks! 😀
Really cool to see!

I'm having a lot of stringing after installing non-stick nozzle and brake. Even with these I got a PETG jam, but I digress, the issue for nozzle thread is updrafts making all the strings accumulate on the heater block. I'm using my own design that blows on opposite ends, though the focus and cooling is excellent, I neglected up-drafting. Do you guys think a triple nozzle offset to create a axial vortex around the extruder nozzle would work?

I'm no sure what the non-stick nozzle is about since searches doesn't really lead me anywhere but regarding creating a vortex with 3 offset air jets, that could actually be a pretty cool concept!
No idea if it would as intended though.

Made this up today, printing it now to see how it works. seeing as im new to the 3d modeling game im pretty sure its not going to do well, but was a good learning experience.

Nice work getting into 3D modeling. 🙂
I have one tip: Add fillets everywhere unless you absolutely have a need for a sharp corner.
Air flow isn't happy with sharp corners so most places, any fillets added will be beneficial without increasing manufacturing time/costs as it would with conventional machining. In fact, fillets will speed up your printing because when the printer approaches a 90deg corner, it decellerates to a full stop at the corner and then accelerates in a new direction. With a fillet, the printer doesn't need to come to a full stop but only to change its direction slightly and thus a higher average velocity can be held.

was a test file to see if it fit right, it did not, onto revision 2.0 , if this one fits ill fillet everything.

Re: Improved fan shroud / nozzle

I have printed and tried Sebastian's Stacks and duct.

These mods are for me a good improvement. I am running my fan now at 70% and I still believe the cooling is improved from the original machine with 85% on the fan speed. I tried PLA for the duct but it sagged so I went all out and printed it in PC. The stacks I printed in PLA.

I am always dubious about changing the machine when it is printing so well but this is easily reversible if it didn't work. It has worked though so I am keeping the mods on there.

Thanks Sebastian for sharing.