Not dual blower, but I did do a dual-fan setup. They're not ducted, because the fans I have are so powerful Ducting could easily be bolted to them though:
Big Fan Brackets for C-Bot by AK_Eric

 

It appears I am not alone by a long shot in using the 300x300 12v heated bed. Nor the RGB LEDs. I am wondering if anyone else would be interested in a custom PCB for the 12volt relay and RGB LEDs combined? I am tinkering around in KiCAD and it's really easy to spin up the schematic and generate a board layout. So I am going to do this for myself to cleanup my wiring a bit more and just for the fun of it.

My idea was to simply have a board with input pins for the following: ground, 5v power, PWM H, PWM G, PWM R, PWM B and then terminals for high amperage 12v-24volt. The PWM inputs would drive IRF3708 Mosfets, I might stick a mosfet driver or transistors in front to ensure they are fully driven to saturation. I've run the numbers for the thermals as well, 25amps through the 3708 generates around 6-8 Watts, so a big heatsink or a fan like I am doing now is needed. Maybe a common heatsink... Anyway in the design phase and just looking to see it's of use to anyone.

If there is interest, I will post up what I have when I am done. Feedback from those that are knowledgable is very much encouraged. I am learning and realize this can be a dangerous thing if done wrong. it's probably dangerous even if done right...

Would also be interested in suggestions for PCB fab shops, there are a lot out there. OSHpark looks promising.

 

Any idea how conductive filament holds up for large power draw? It *seems* like you could just make it as thick as you want, but I don't know if it could handle that much without melting or catching fire.

 

I have used OSH Park several times. They do great work. Takes about a week and a half turn around.

 

I've no experience with conductive filaments. From what I've read, they require a hardened nozzle and are hard to purge. It would be very cool to try out sometime.

I would give them a shot for low amerpage / voltage stuff, but think I would shy away for this one.

 

Hi Eric. Yes I have seen those. I never had much luck with axial fans, but never went that big. Don't you have problems with cooling the bed?

 

I actually switched out to a single (big) ducted fan on the back: Just posted about it a few days ago & gave the thingiverse link to the duct.
Surprisingly, I never had problems with it cooling the bed. Just knocking parts over at full power

 

Thanks for the input! The build looks very neat, and logical, and efficient, which is what I liked about it. I am relatively mechanically and technically inclined, so I am not terribly concerned about that part of things, and I have been and continue to learn details about 3d printing itself working through the details with my current printer, which is anything but plug-n-play.

I have considered a 300x200 build as I know there are more readily available and affordable options for heated bed, and I believe the original and a few others documented here use that bed, so I could stay pretty close to one of the reference builds. I also have considered building for 300x300 but sticking with the 300x200 heatbed to start, upgrading later. Perhaps following the reference build, and knowing one can always swap out a few extrusions and change the overall geometry later would work!

I have started working through the thread, and will continue to lurk for a while as I absorb what I find. Again thank you!

 

I am working on something that should work for the stock setup for those that are interested.

 

I thought that I remembered reading that somewhere. Good to know. Any suggestions for a particular model? I assume that they're quite inexpensive. I'm running a 24v/25A power supply.

Completed my first "benchy" last night. Meh; not bad. Used the 0.8 nozzle and 0.2mm height.

 

Never tried without them actually, they've been there since day one.

 

Pretty good for a .8mm nozzle as far as lack of blobbing during the retraction.

 

Here is a "mount" I developed that *should* allow you to connect the @AK Eric fan duct he just developed to the stock hot end gantry. I haven't tested it, but the dimensions are right and everyone knows that nothing can possibly go wrong if the dimensions are right...... If you want the F360 files I used to develop this I am more than happy to provide them to whomever.


AK Eric Fan Mount v1.step

 

Looks great. I've been trying to do this type of duct for months, on and off, in OpenSCAD... Have any knowledge of OpenSCAD by chance?

 

LOL no, but I am starting to learn it. I am super comfortable with the syntax but I am still learning how to make things in it ha ha.

Just to be 1000% clear and fair I didn't develop the duct, AK Eric did, but I designed this LITTLE tiny piece to make it work on the stock setup (he has a Volcano which is taller, etc...)

 

Right on.

re: Fan Duct author. My goof, missed that. @AKeric, do you have any knowledge of OpenSCAD by chance?

 

Ooh! I was eyeballing AK Eric's nice fan duct and was going to work on a bracket to adapt to the rear plate for us regular E3D users, but you beat me to it! Good man. I'll probably try this out tonight.

 

I've poked at it, and I like it: Good for parametric stuff. But no, I don't 'know' it.
I modeled up that duct in Maya out of pure polys, so there's no way to 'get it into openscad'. You'd have to model up something similar there from scratch. I've been using Maya nearly every day of my life since it came out ('98-ish?) and Alias PowerAnimator before that, so... I have a bit of momentum behind my software choices

Really, I should just change that duct so rather than a hole for where it connects to the bracket, it's just a "long open space": Then it could slide up\down as needed for different extruder systems. I modeled it really fast as a prototype. If I get some free cycles I'll try to modify it to be a bit more adjustable. But @Matt Mathias mount is a great alternative!

 

I'm just wondering.. Is there any interest in collaborating on a C-Bot library in OpenSCAD (or OpenJSCAD, or ImplicitCAD)? I'd be glad to lend some cycles to it if so. I want to see what type of challenges are involved in maintaining a "hardware" software project between multiple contributors is feasible. The vast majority of OpenSCAD code out in the wild is very hacky (especially mine), and I think it could really expand the ability to integrate individual modifications. If we can even settle on some common libraries and calling module conventions it could reach a critical mass for developer contribution.

For instance, @Chris Roadfeldt 's awesome hot end generator could import any specified extruder plate and either print it in place or ensure that the exact right size area is left for the extruder to be bolted to the hot end plate. If we standardized on a few things, this would be trivial.. but without agreement you can't do that because you wouldn't have assurances about the location/orientation of the imported extrider.

 

You have this as an STL file?

 

I've thought about doing this as well. I think it would be great and make it easy to have something like this build custom designs for the entire printer. However right now I don't have enough free cycles to build it. If someone were to take it on I would gladly help out however I could.

 

I've been mulling over building parametric corner brackets with in-place printing to make squaring the build easier.. When (if) I get around to it I'll make sure to start a library as a separate git repo.. Unless, of course, anyone here beats me to the punch

 

Round 2 IT by MWProtoType

There. Now get to it.

 

Here you go, let me know how it works. My printer is torn down right now while I install my Flex3Drive....in fact I will probably never use this piece, I designed the mount into my Flex3Drive gantry.

 

That would be amazing! Please provide as much as you can think of Right now I'm most interested in the definition for the V slot indents that the brackets have, but I'm certain all of it will be useful.

Oh, and when you hear coders talk about cycles -- it's just an inside joke about CPU clock cycles, we're really just talking about time

 

Ha! I didn't even realize I had said cycles.... It's been a part of my vernacular for so long.

On a side note, I started making updates to the generator last night. Here's the planned updates.

* Move hot end to the end of the carriage instead of middle. - Allows for more compact layout and shrinking of carriage.
* Move probe to same carriage side as hot end. - Reduce overall chassis footprint needed. More Accurate probing.
* Shrink overall width of carriage. - Reduce overall chassis footprint needed.
* Fan duct - Finally finish the work to build an auto generated duct, perhaps similar to the design @AK Eric designed.
* Add option to mount LEDs.
* Add direct drive options. - @Carl Feniak 's design and @Elmo Clarity's for the Titan extruder.

If there is anything else folks would like to see, let me know.

 

I was gonna mention direct drive.. but you edited before I got to it

Do you have support for the cheap endstops? If not I would like to see that -- the indents in the C-Bot are perfect for those.