Glad you're back on the thread. Keep the improvements coming! Triple C is my fall back.

Heard that the Sailfish code is highly tuned compared to Marlin.....but Marlin should still be viable assuming some ifdefs?

Having the belts hidden in the rails is pretty clean. I'm more interested in creating a heated chamber, than an outside shell on the printer, so the steppers would be mounted outside in cool air. Also planning to do the twist-belt-cross-over so the return belt from the stepper would still be inside the 20x20 Y rail.

I'm starting printing tweaks on a 3 wheeled xy_barEnd with inline belts for a 20x20. The tension wheel on the bottom looks like http://www.thingiverse.com/thing:110283. With stacked belts, 4 wheels would be the only way to go.

Dan Newman's designs use linear bearings and round rails. An advantage of this is he doesn't have the X rail separating the belts as they connect the X-carriage, creating a torque moment. The belt forces are pretty much inline driving the X-carriage. I'm trying something similar, by putting both pulleys on one side of the X rail.

 

Hi Adam,

A friend and I are building off your design and I came across something odd (after printing them, doh!) with the X and Y Idlers. Is there a reason the dimensions for the v-slot spacing is different between the front/back and side openings?

I'm doing a mock-up in Blender before making the big "cut extrusion" commitment and noticed that one of the openings is larger than the other. I also verified with some calipers that they are about 0.4mm off (one opening on a printed part measures 40.15mm and the other opening is 39.75)

Also, for the Z-end 1 and 2, there are two of each, right? Trying to reference your pictures and it looked like you had one of them printed in red...

Thanks much,

-Joe

 

I've got a couple outstanding questions while I wait for more parts to arrive:
1) What did you do with your thermocouple wires? Did you use normal copper cable (twisted?) to extend them down to your mightyboard? I saw some lengthy discussion on a google groups forum about using "type-k" wire for the thermocouples...
2) Where can I find the 2 and 4 position connectors for the mightyboard? (i.e. power, ex1/ex2, hbp, thermocouples, and cs-fan) I found this one on digikey, but not sure if it's the right one:
http://www.digikey.com/product-detail/en/20020038-H021B01LF/609-4585-ND/2683192

Thanks in advance for any info/help...

 

Any standard hookup wire should work for the thermistor. Type-K is not a wire type, but a type of thermal couple. Those are not used much since the thermistor tends to be more accurate and it takes special circuitry to use a thermocouple.

 

Thanks for the reply, Elmo...

However, the controller I'm using, a mightyboard, uses thermocouples for the hot-ends. I have two thermocouples, but the wires are a few feet shorter than what I need (unless I end up mounting the mightyboard up above the printer)...

 

Any hookup wire will still work. Try using the same guage wire as what is currently on them.

 

The pictures don't seem to be showing for me, but the vids are definitely impressive!

I'm very interested in hearing about you getting Sailfish running on your Azteeg X3. From what I can tell, the Azteeg board looks to be a bit more robust than a Mightyboard. Are you able to use ReplicatorG and/or Makerware with it?

I've downloaded the source ball from github a while back, and also installed the toolchain(s) in order to compile it. Any other gotchas with loading Sailfish on the X3?

My build is progressing... I just ordered my closed-loop GT2 belt this week and I temporarily hooked up all the steppers to a RAMPS board I have (in order to test steppers, wheel fittings and such) and got it moving

I also modeled/printed two brackets for the X and Y endstops. At this point, I'm trying to determine which is going to be my X and Y axis and whether or not my endstops are going to be MIN or MAX. Looking at your videos, I think my X will run parallel to your moving Z-bar, and my MIN will be in the far right corner.

Thanks for keeping us updated on the tuning/tweaking of your build!

 

Hey Adam, how did you go about fixing your mirrored prints? Just move the endstop to the other side and flip the wires to the stepper? I've got about a kilo of prints here that I've realized are mirrored. I was going to blame Simplify3D's FLIP setting, but no matter which direction I flip it, the print comes out the same so it appears that setting is only for visualization in the gui.

EDIT: Wait, fixed my X mirroring by inverting both motor plugs and also swapping them. then telling the firmware to home to max on the X direction.

 

It's always something! In Octoprint I can flip the jog controls to match the printer, because mine is the same way depending on how you look at it. Looking from the front, the origin is the back right corner so which direction does the "Up Arrow" move the axis? It is a mystery!

After spending all that fun time building the bowden force sensor I am not super happy with the bowden concept (9mm of retraction just to get rid of 90% of the blobbies!). Did you make your own mount for your extruder? I see that the XY carriage has a block to mount it to, but I'm wondering if there's a plastic part on the extruder that mates with that or if the mount is part of the extruder assembly you have.

 

I do love non-bowden. My i3 was a J-head with a wade's extruder, which probably cost a total of about $30 and it produces some really really great prints. It's just the machine around it is pretty unreliable that prompted this whole upgrade. Now I've got a $200 hotend that needs a fan running on it all the time and the quality has gone down. I'm not a big fan of having to sling around a motor on the XY carriage but my i3 does it just fine so I don't know why I was so hesitant to just do the same thing. The torque doesn't seem to be an issue though so it should be fine without the wade's gearing and just using a direct filament gripper like you are.

I definitely need a part cooling fan though too because that makes so much difference in print quality. That one you linked is a monster, I love it!

 

Hi Adam,

Firstly, thanks for sharing your build!

I'm designing my own printer with a heavy influence from yours. Just wanted to ask for a few close-ups of your Z leadscrew where it meets the lower mount and bearing. Are you using leadscrews with turned down ends that just slot into the inner bearing race? If so, aren't these bearings not rated for axial loads?

Thanks,
Austin

EDIT: Just seen the picture and description of this on the first page of the discussions. These bearings aren't rated fro axial laods though. Have you put a heavy weight on the print bed and noticed any increased friction at all?

 

No worries! At least you're back up and running...

Thanks for the pictures. If you could link to the google group/thread you mentioned I'd appreciate it.
And regarding the bearings. It sounds like you had it wrapped up already. 5Kg sounds plenty capable. I suppose the only issue I could foresee is a slow wear and widening of the bearing grooves in between the races resulting in play in the Z axis.

Nothing to be worried about though i'd imagine.

Thanks again.
Austin

 

So where in Cali did you end up?

 

Typically a ball type bearing and handle ~25% axial load relative to it's radial capacity.