Fan shroud?

Is there a fan shroud available that someone designed for RoBo 3D to direct airflow from the fan more directly to the print? I've seen few other more expensive printers come with a cone-shaped shroud on the fan - I was wondering if we can mod our RoBo with the same. Thanks.

 

We can definitely do that. I was talking with someone about it yesterday and they brought up a good point. Do you design it for the stock fan holder and hot end? Or do you design it for the E3D hot end and custom fan bracket. If this which custom bracket?

 

Yeah, that's a good point. I do use E3D with the replaced fan bracket, I believe this one - http://www.thingiverse.com/thing:186027

BTW, I'm thinking about adding a second fan in front, but not sure for now if the same bracket will fit...

 

I have the E3D and was actually trying to design an offset, elliptical nozzle, cone-shaped duct today. I am having a lot of problems creating the wall thickness in Sketchup Make. I tried zero thickness but could not get Slic3R to cooperate. I will try one more time with Sketchup but it may be time to move on to openSCAD or something else.

The 40mm fan needs to be moved behind the X rail a bit because I don't think there is enough room next to the E3D fan shroud.

I will post it on Thingiverse and put a link here when I manage to get it done. I think a higher airflow is really needed. With the current setup I get more layer melting and "swelling" on edges opposite the fan. I was going to try the duct first and then go to two fans or one large one if that was not enough.

 

I'm having exactly the same problem! Right now I got a large room fan blowing on the working printer from several feet away, to alleviate the problem...

 

Yesterday I installed a front fan. Actually, I replaced the existing back fan with a better one (Noctua) and installed the corresponding front fan. After cleaning up and tidying the wires, I gave it a spin. So, the cooling is now slightly better, but still not perfect - I still get sagging overhangs. Not sure if bridges will work either - need to print some samples. So, I think the summary is that we do need a shroud or a fan duct. Or maybe I'm doing it wrong...

 

Ziggy and I have been talking about this for a while now. I have been using bent metal from a coke can but am looking at designing a duct, just trying to decide what style would be best.

 

I have been working on a new bracket and fan duct. I've printed my first prototype and it increases the cooling efficiency massively but I'm having the issue where as soon as the fan kicks in on the 2nd layer the hot end plummets in temperature (196 deg to 170 deg and further). I have to manually adjust the fan speed right down and gradually ramp it up but to no more than 50% otherwise the hot end can't keep up to temp. I'm using the stock J end. Any help would be appreciated. I'll post the bracket and fan duct on Thingiverse now (though the duct needs some adjustments) and then add the links here. I hope we can collectively come up with an awesome solution.

http://www.thingiverse.com/thing:270506

 

Wow, nice design and rather clever mounting! I'll try it on my RoBo3D with E3Dv5 installed...

 

I am messing around with a design for the E3D hotend. Some photos here:
http://forums.robo3dprinter.com/index.php?threads/e3d-installation-question.1380/page-3#post-14382

Galaxius, your design is very nice and I like the adjustability. What design software did you use? My design is fixed for the E3D hotend height. One idea that mine adds though is a clamp for the wiring harness. I can see a hybrid of your shroud and my wire clamp. I think I will mess around with them.

If you use Slic3R I find it important to use the proportional fan speed settings. You need to calibrate the max setting for your particular print fan. I find a lot of variation between fans. Too much airflow and layers will not stick at all.

Also to keep these resources under the "Fan Shroud?" post name, here is a link to Ziggy's design which
I think is a great idea also:
http://forums.robo3dprinter.com/index.php?threads/extruder-cooling-fan-mods.1821/#post-14098

 

Denys, If you try Galaxius' design let us know how it fits with the E3D depth and heating block size. Thanks.

 

Hi SteveC. Nice duct design, I like how you've done it in layers so you can have a complex final unit. I'm using this cable holder by tonycstech, it was the first mod I printed. It's a firm fit and holds the cable bundle very well.
http://www.thingiverse.com/thing:227307
I'm also using this Z axis cable guid by melodybliss with the Robo3D case off.
http://www.thingiverse.com/thing:209034

I'm using Rhino3D for my designs.

I saw Ziggy's design but had almost finished my duct. I also wanted to take advantage of the stock fan and mounting points and wanted to design a secure sturdy bracket that could be used by other people to mount their own fan duct designs. I'm going to print another bracket when I print my revised duct design and get another fan so I can have cooling from both sides. I'm currently working on a wind deflector for the hot end to try prevent it from catastrophically cooling with the fan first kicks in. My current prototype, pretty ghetto, works somewhat but i have to manually baby the fan speed for the first few mins until i can get it up to the full speed setting i have.

I'm using the proportional fan speed setting but even kicking in at 30% on the 2nd layer cools the hot end too much. Is there a way to configure slic3r to say kick in at 10% for the 2nd layer then increase to 20% for the 3rd and so on until it gets up to the desired full speed and can go to auto?

Once I revise this fan duct I was thinking about working on one that circles the hot end but if i run with a dual fan duct setup there's not really any need. The only problem it'll be harder to see it printing.

 

Thanks for the design Galaxius. I found this yesterday on thingiverse and was actually just about to start a thread about it but I see you guys already beat me too it.
I will let you know how it helps once I bolt it on there, I don't have the e3d however so I won't be able to comment on that.

 

Okay quick update on my first run with the new fan shroud. The good and the bad.
The tough part, and I'm sure that is one thing you're working on Galaxius, is the duct clearance issue from the bed itself. I actually threw my bolts on the first try as the duct bottomed out just shy of home before the nozzle. I did manage to file and tighten the bracket just enough to get it to raise up a touch but man there is zero room for error and I'm worried every time I home that it may bottom out again. (see first picture with the nozzle just a touch too high)
Aside from that this is so close to being right on the bed that the fear was it would scrape off anything that was just layed down as it dragged over it.
The plus side, which is huge, my fear didn't come true and it worked like a charm. It didn't scrape anything off and I managed to finally print off a part I have been having trouble with. Keep in mind I didn't have ANY fan on here prior to this. My Robo didn't come with one.

I have been printing great prior but the one thing that has drove me nuts was the fingers from the Robohand project. Their small size and overhang angle has been a nightmare for me but this whole time a fan was my answer. (second picture)

I love the bracket and will definately be first in line for your next update on the duct itself.
Thanks again.

 

Matt, I tried playing with the Tapir duct design and failed miserably. I struggled getting the correct dimensions, then getting it manifold and getting Slic3R not to do crazy things with it.

One thing I did notice with my simple conical duct that I have no problem with the hot end temperature dropping. Now this is with the E3D and I think what made the difference is that I oriented the head so that the heater cartridge is in the back near the duct so the thermistor is blocked by the heater. If the thermistor area is directly in the airflow then it might give an artificially low temperature. This is my speculation and may not work for the stock J-head. The newer Robo heads with the ceramic heating cartridges may heat and respond faster.

I haven't given up and will still work on a surrounding duct.

 

I started with the STL file. And tried to use Sketchup and Meshmixer