Agree Labern! Blowing on the Teflon coupler has as much effect on the inside temperature as blowing on your fridge at home has on it´s inside temperature.
could you please provide the link to your fan shroud on youmagine?
I haven't had time to load it yet but I will soon and ill post it here. It does require a lot of insulating against the heater block or it will deform. hence why I think a metal version is really the best way to go.
Does it have any impact on the print head size?
Interesting thread, I'm looking at the fan duct too, I'm using Mnis' fan duct and noticed an improvement especially on the left ear of the Ultimaker robot, although I wasn't sure what all the little holes are for other than perhaps preventing over pressure. But I do like the way the ducts can swivel out of the way for access.
What's the recommendation on the angle of the fans? Horizontal or Angled?
I'm looking at getting the flow centred about the nozzle but not fighting each other's flow and I may experiment with a thin heat shield to protect the heater block.
The many small holes are there to eliminate the heat accumulation above the Hotend so that the fan cages can not deform too much.
A slightly unfair comparison ...If you additionally cool the radiator of your fridge, then significantly less energy will certainly be necessary to maintain the preset temperature internally stable. The area above the UM2 printhead has no temperature control and the small rear fan blows with a maximum available power. I mean this little fan is undersized. And as far as I know still lacking any evidence regarding efficiency or inefficiency of a stronger cooling above the Hotend. However, the Ultimaker 2 will fail without cooling the ColdEnd after a short time, this is certainly widely known.
Of course, I will not force anyone to use my designs, that I certainly do not need. Sorry if someone sees it that way It is more important to learn from each other to get a really good product. I saw your test results and was very pleased. This reminds me that I have so far not made any extensive testing with my designs. Unfortunately, I lack the time also, and I was hoping that someone can make more intensive tests, the more I would not say so...
I really like your design and want to test it when it has reached a nearly completed Status. it looks a bit like an ark of Noah, it suggests me feel safe and I like that very much :lol:
Anyway, a few suggestions from me:
- I think the nozzle tip looks out too far, maybe you'll get better results with a cooling closer to the object surface.
- To avoid in certain places a large heat storage, you can try to realize smaller air passages.
- Fast print speeds make it generally difficult to cool freshly oviposited material efficiently, therefore take some users large additional fans for an extensive object-cooling.
- If you are constructing it mainly for normal users, then it must be easy to implement. For example I see at my (really) big universal feeder a large negative effect that many optional components seem rather daunting. And that's really a shame, because the thing actually works many months without any problems extremely reliable.
- The cooling of the entire printhead plus a sufficient material cooling was my main Goal for CPv9. Remove heat directly where it arises, and to avoid mixing of air streams, I still see as very important. As a result, everything is kept very much cooler above the Hotend including the insulator-screw, and this gives the entire PTFE little more overall stability. More than that, my main CPv9-Design makes the third fan (...these annoying and sickly printhead cooler) totally unnecessary :mrgreen: Of course, me being aware that the critical transition zone from Hotend to ColdEnd can hardly be cooled efficiently enough. That would probably work well only if the ColdEnd would be made of any metal.
By the way, I also have a few test objects are printed with this head lift feature in Cura. For some special PLA varieties, a setting of up to 0.5mm works perfectly and there are no visible disadvantages for me. Thus, the nozzle tip does not go against warped material edges and causes less mechanical stress of objects with a small footprint.
Tip: Some old USB Harddrive enclosures for notebooks etc. have different thicknesses of sheet metal cages made of aluminum or copper for electrical shielding purposes that are sometimes coated on one side with glue. Often, these sheets can be reused for other purposes, simply cut to size with scissors they might pass as a heat shield for printed fan Cages.
I would very much like to be able to see and test many of the available fan cages when they were made entirely of metal. Maybe we should design the fan cages so that they can be folded out completely from a piece of sheet metal, just like the original.
I am looking forward to be able to see more details of your design.
I'm currently printing off objects with different nozzle sizes and will post pictures here when done.
Fan angle doesn't really matter that much, I have experimented with a hole range of angles but settled with horizontal. what is important is giving the air room to pick up speed once it has passed through the fan. so if they are on an angle you would need to reduce your build volume to do this.
Yes it does look like a boat. personally I don't like it but it really comes down to performance
I did not think you were forcing me to try your design and yes sharing ideas is best.
I actually printed the fan shroud with slotted holes so I could raise it up and down. the height you can see it there is the same height as the original. I found this to be a good height. it allows enough room for the air to escape without slowing down. I have done smoke tests to watch where the air travels but its to hard to see in the video, I was able to watch in person.
I originally was just going to fold up something like this
But instead decided not to. I have already started designing the folded out version of mine to try. I might just end up making one myself. will be cheaper than getting it made. I just have to make some free time and overhaul our old folder at work. Its in a bad state at the moment.
I think pm_dude wanted to know if your variant reduces the printable area, or have I got it wrong?
oh, you maybe right.
No, it has no impact on the printable area.
Its widest point is the same as the widest point of UM2 Original Metal Shroud.
:shock: Hm, I could not manage it exactly ... Is it because of the long screws? Do you use the smaller width in the region for the fans? Maybe you can give me some dimensions?
Original shroud with fans mounted at widest point measured to be 99.6mm. My shroud is 100mm wide, .2mm either side is nothing to worry about.
I didn't have any issues with the old one hitting the sides or my new one.
Tried out my Fan shroud with a 0.25mm Nozzle, Turned out quite good.
when you will be happy with the results please upload the design so we can use it too.
I'm interesred too in your project. I'm awaiting delivery of an Olsson block. The present fan system is suboptimal for printing small parts (if you print only one small part like the famous "Marvin"). When Ultimaker decided to stop dual extrusion for the UM2, they should have offered at least an optimal single hotend (which I would even pay for). At the moment it looks, like UM2 product development goes towards customers (I remember the statement of Sander van Geelen; of course he didn't say this in my words ;-D ). But "tinkerers" can be quite innovative and successful.
When a satisfactory shroud will be made of metal I'll order one too.
Kind regards from Paul
PS. When a lately removed the shroud, it gave me a hard time, since it was "glued" to the nozzle by ca. 1-2 cm3 of leaked (?!, I have no clear idea why / how it got there) brownish plastic mass. I had to remove it with the aid of a soldering iron.
Well today my replacement fan arrived for the main head.
I orderd and recieved the Sunon MC25060V2-A99 of of ebay from it-tronics.de.
So what's the difference I hear you say?
Well I can actually hear you , initially the lead was a bit short so also having a raspberry Pi and loads of stuff to play with I extended the wires and then added the connector.
I got them from www.proto-pic.co.uk, both the housing and the pins.
Connected it up and turned it on!, bugger can't hear it had to check it was spinning and it was wahoo one happy bunny,
Before I took the old one out I checked the airflow with a windoo skywatch 3 and got about 2.7 to 3.1 m/s and a dB of 67, I SAID 67.
With the replacement fan in place the air flow was again between 2.8 and 3.2 and the dB was only 45dB I done a few test runs this afternoon and so far everything is running fine.
Now it's a lot quieter sitting next to the UM2 as its printing, well worth the £15 ish for all the bits, would have been a bit better if the leads on the fan were just 4cm longer
Yes I replaced that one a while ago. Its a nice upgrade. Now I want silent stepper drivers, Then it would be awesome.
I found it easy to de-solder the wires from the old fan and solder them on the new one.
Printing a slightly refined shroud now. If it turns out good ill post it on youmagine.
With silent stepper driver you meant the complete replacement of the UM2 mainboard?
Or is it in the matter to the UMO?
Yeah apparently it would be really difficult to do, But i was just dreaming
Maybe we can push them to implement it into UM3
At the moment I'm not sure if I would ever buy another Ultimaker machine :roll: I think it was in the past, too many avoidable problems :huh: Rather, I want to try it yourself to design a machine, and as many parts as possible then I produce with my UM2 :lol: Hopefully it does not remain just a dream
I'm about to fit an Olsson block
At moment I use the Venkel designed fan shroud, I am altering the design to fit Olsson block lowering it and filling in the base, any thoughts on this till there is a better design.
You can try mine if you want
Have just loaded it on youmagine and you can find it here: https://www.youmagine.com/designs/um2-dual-fan-shroud
I have been using it and am finding it good. Please give me feedback on printability, I used XT-CF20
This may seem like a silly question, but why do designers of fan ducts for the UM2 connect the left- and right-side ducts across the middle in front of and below the hot-end?
Wouldn't it be easier to have two pieces - a left- and a right-side duct? Seems like this would alleviate issues as to heat from the hot-end.
If airflow needs to be directed away from the hot-end, connect the two pieces across the bottom with a thin piece of metal, like the piece of beer-can Venkel used as a heat-shield on his version.
I really like parts of your design and I tried to use some of your features in mine. I do have designs that have clip in fans etc..
The only reason I didn't just download your design and use it is because I wanted as much air blowing on the print as possible and I'm not really concerned about air blowing on the Teflon isolator.
If you would like me to try it so you can see how it compares I can (and probably will anyway)
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