Hi Carl,

Yeah, I could probably get away with a simple mechanical switch, but I already bought all these mightyboard endstop switches, so might as well use them

I actually have two versions of the bracket. The first one works with the original back-X plate, and the second one works with the new direct drive back-X plate.

Here are some pictures of the endstop modification and the old/new brackets, along with the bracket STLs.

The new bracket needs to be modified to shift the fan mounting pillars to the left enough for an M3 nut to secure the fan hinge.

And, yes, those are "rivets" I didn't have any really tiny screws to secure the switch, but the rivets fit perfectly... lol

 

In the message with the V2 files for the direct extruder, there are a couple other files for a fan duct and mount. I printed those up and attached it and it looks like it might be too low for my E3D v6 hot end. Has anyone else tried this with the v6?

 

This is a good resource: Marlin firmware user guide for beginners | Solid Utopia
@AK Eric also has some good setup tips on his blog page Building the C-Bot 3D printer: Part 18 : Software Day 3 : Tuning movement settings

 

Finally, I got through all the pages. Phew.

Quick question that just came to my head while helping a friend build a Prusa I3 derivative: Besides the obvious reason of being able to "hide" the belts in this build, what are the advantages of using V-Slot and wheels instead of rods with linear bearings like most other builds?

Rods + bearings seem to be cheaper, easier to put together and require less adjustments?

 

The reason most important for me about using V-Slot over rods is flex. Your print quality will not be as good if you use rods. There are many discussions over on the google groups 3D Printer Tips and Tricks about rods versus extrusion.

 

Round unsupported rods lose rigidity on longer spans. A 20x40 in the c-bot's orientation is much stiffer and probably good for .75M to 1M gantry. I bet you would need 25mm or so round rod to span a meter, who knows what that would weigh.

 

Thanks for the quick replies guys. Guess it helps to stay up late at night in a totally different timezone .

There have been a few remixes to this design for different sizes, but also belt layouts, etc. Since you have your version running for more than a year now, Carl - are there things you'd change from your original design?

 

Oh sorry. I meant "belt layouts" mainly for the Z axis to avoid multiple steppers.

As for the endstops - I always wonder why people have them on the moving parts when there's a perfect static place on the other side.

 

I think the main reason for putting the X endstop on the moving piece is to reduce the number of wire runs back to the controller board.

 

I preferred to put my X endstop on the print carriage so that the printer can always home each axis independently and it can always do the default homing of X-> Y-> Z.

If you put the X endstop on the side then you have to flip X and Y orientation and always home 'X' before 'Y'

Putting the endstop on the print carriage adds an insignificant amount of mass compared to the aluminum H bar and hot end.

Just a preference and like everything on this great design, it's all customizable.

 

Not at all: I presume you mean my Configuration.h and Configuration_adv.h? Find attached

 

I think your message got buried earlier.
I believe this is the fan duct I remixed and put on my Cbot.
I'm using it with an E3D v6 and it all fits, let me know if you need help.

 

Thanks for the design. I'm currently sourcing parts for a 12" cube, but after that I would like to build another that's at least 24x24" build size in XY. Has anyone else built one this large that can share their experiences?

Also, do the current set of STLs reflect all the mods and feedback from this thread? I read through all 40 pages but it's a little unwieldy and difficult to keep track of what's changed for the better or worse.

 

@AK Eric built the biggest version of this printer that I have seen
Building the C-Bot 3D printer: Part 1

 

Thanks for the replies - yes, I was considering the 3-screw Z-axis, probably with a NEMA23 motor. I was considering a 3rd vertical for the Z axis as well to stiffen it -- is it better to have the screws near to the Z-axis linear rails or further away? Not sure if the bigger motor would be useful on XY axes as well. I'll probably increase the XY rails to 20x60 and I'm planning to enclose the printer as well -- probably with dibond panels, which should add quite a bit to rigidity. I'm a bit worried about noise from resonance but I think it should be manageable.

 

Has anyone seen vertical lines like this before?

Does it have to do with the idler bearings and GT2 belt patch? I know there are parts of the X and Y belt path where the GT2 belt has teeth facing the idlers... is the belt supposed to twist 180 so that the flat part faces the idlers?

Thanks in advance for any help, as this is driving me up a wall

(BTW, I do see the traditional ringing that follows left-side edges, and think I know how to fix that. I'm most concerned with the consistently vertical lines)

 

I think I resolved the vertical lines with adding a 180 degree twist in the long-run side of each of the X and Y belts as they leave the X/Y steppers...

 

Here are my endstop brackets.... X is on the direct-drive extruder carriage. I'm also attaching a modified carriage front that can be used with a hexagon hotend.

 

Yes, I shrunk the lip on the groove mount from 5.6 to 4.6mm.