Which core XY should I build?

I like the idea of the core XY but am confused by the variety of designs out there.
I am thinking of a 200 x 300 mm bed with a stable diamond hotend with 3 bowden extruders for colour mixing.
I will only be printing PLA but need to keep the overall design size as small as possible in the X and Y direction.
The x carriage should be strong and stable enough to handle the diamond hotend.
I will be using duet electronics with a dueX4 add on board.

I will need to do some modifications to support 3 extruders and 3 reels of filament.

So my question-----which completed and proven design would best fit my aims?

Thanks for any advice.

---

appjaws - Core XYUV Duet Ethernet Duex5
firmware 3.1.1 Web Interface 3.1.1
Ormerod 1-converted to laser engraver, Duet wifi
OpenSCAD version 2020.07
slic3r-1.3.0, Simplify3D 4.1.2, Cura-4.4.1

There doesn't seem to be a good set of plans or CAD design available.

Go with Guide rails
They can be had on eBay inexpensively

If the Digital Dentist comes out with a design that would be great.

Rectangled has a nice design in
[forums.reprap.org]

Would be nice to have a good design / kit
so a bunch of people have the same design to beat on!

In my experience even half decently built X-Y axis work great.

Z-axis is where you should put your attention at.

Quote
cozmicray
If the Digital Dentist comes out with a design that would be great.

I'm working on it...

---

Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

You could make one of these [www.thingiverse.com]
It seems pretty popular and I think you could remix it to take a different hot end

Quote
the_digital_dentist
I'm working on it...

I'm very curious what is that going to look like.

---

RepRap Lander concept on Concept Forge
RepRap Lander concept on RepRap Forums
My Things, mostly experimental stuff

It will meet all the basic requirements for a quality printer and look a lot my current machine:

Rock solid 40mm square t slot aluminum frame
electronics in a drawer?
fully enclosed
linear guides for all linear motion
32 bit controller
DSP drivers on X and Y axes
no autotramming
high voltage supplies for motors
minimal/no printed parts- all metal

and
XY assembly on a flat steel plate (?)
bed lifted by 3 screws and 1 motor
heated bed?

print envelope: 300 x 300 x 600+ (?)

As always, print quality will be highest priority. I will control costs by using used parts wherever practical (I already have 3x Japanese linear guides from ebay and all frame parts from a scrap yard) and doing all required machining myself.

---

Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Sounds good for a high end machine on the reprap spectrum. Will you document its build somewhere or you will make all documentation when you finish it?

Edited 1 time(s). Last edit at 04/06/2016 02:44AM by realthor.

---

RepRap Lander concept on Concept Forge
RepRap Lander concept on RepRap Forums
My Things, mostly experimental stuff

Documentation happens as I build. As components are acquired they get modeled in CAD. When major assemblies are thought to be final, I build and test them. I'll be using some of the same type components that are in my current machine so I already have some of the CAD models ready to go from that build.

---

Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Note that the D-bot is a derivative of Carl Feniak's C-Bot, and there is also a "triple C bot" which is the same idea but with three leadscrews (one motor + belt).

[openbuilds.org]

All three printers share the basic concept of using 20x40 v-slot for structure and wheel + carriage on v-slot for motion components, and it's pretty easy to scale the design.

Thanks for all the replies, I have decided to build a D-bot and am in the process of ordering parts.

---

appjaws - Core XYUV Duet Ethernet Duex5
firmware 3.1.1 Web Interface 3.1.1
Ormerod 1-converted to laser engraver, Duet wifi
OpenSCAD version 2020.07
slic3r-1.3.0, Simplify3D 4.1.2, Cura-4.4.1

How about a belt drive Z axis?

Something like this using one motor



Have to look at belt forces and whatnot to balance out
pull and tug?

Cheaper than leadscrews?
May have higher resolution?

Quote
appjaws1
Thanks for all the replies, I have decided to build a D-bot and am in the process of ordering parts.

Let us know how it goes, I'm curious for this printer how easy it is to get all of the different parts vs buying one kit

Quote
cozmicray
How about a belt drive Z axis?

Something like this using one motor

[attachment 76055 Belt_Z.jpg]

Have to look at belt forces and whatnot to balance out
pull and tug?

Cheaper than leadscrews?
May have higher resolution?

Build the prototype and show us if it works well!

Quote
the_digital_dentist
XY assembly on a flat steel plate (?)

This means that it will be doable only by guys with access to a machining shop to cut the plate for them right? You are talking something like this: [youtu.be] ...

---

RepRap Lander concept on Concept Forge
RepRap Lander concept on RepRap Forums
My Things, mostly experimental stuff

Yes, similar to that.

I'm building one machine for my own use, and not planning on going into mass production. The priority is on print quality, not absolute minimal cost (though cost IS always a factor) or ease of construction beyond tools available to me. If I run into something that's too hard for me to do or too expensive for me to have done, I'll look for alternatives, but I'll try not to compromise the print quality to make the thing buildable for $300. I'll probably spend >$300 on the extruder/hot end/controller board alone.

If I use a piece of cast aluminum tooling plate for the XY mechanism base, the hole cut in the center of the plate may become the print bed plate and other parts, so material use will be relatively efficient. I can deal with the thermal expansion of the plate by adding a second bearing block to the X axis guide rail.

---

Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Quote
the_digital_dentist
If I use a piece of cast aluminum tooling plate for the XY mechanism base, the hole cut in the center of the plate may become the print bed plate and other parts, so material use will be relatively efficient. I can deal with the thermal expansion of the plate by adding a second bearing block to the X axis guide rail.

I thought about that too but that alone will be around $100 easily.

---

RepRap Lander concept on Concept Forge
RepRap Lander concept on RepRap Forums
My Things, mostly experimental stuff

Quality costs.

---

Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

Quote
the_digital_dentist
Quality costs.

As expected... but most people don't get out of the 3D printers something that is worth that quality in parts. That's why most buy $300 printers/kits.

---

RepRap Lander concept on Concept Forge
RepRap Lander concept on RepRap Forums
My Things, mostly experimental stuff

Yes and no. While you may not need the print quality that a more expensive printer can produce for Yoda heads and tugboats, a high quality machine has benefits beyond print quality.

1) You can print things that require precise fit, such as gears, threaded parts, etc., that you might not be able to print successfully on a machine that is not so well built.

2) A higher quality machine is generally more trouble free than a crappy one. There's less adjusting, repairing, and modifying to do, and it prints more reliably. That translates into less wasted time which is the best return on your investment that you can hope for (unless you don't value your time).

3) The feeling of accomplishment that comes from making something truly awesome as opposed to making something run of the mill has value.

4) Education- there's a lot to be said for working on a design that's better. You have to really think about fundamental concepts like quality and reliability and how to translate them into hardware. Lessons learned are applicable to other endeavors.

---

Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

I can't tell what material the mounting plate for the guide rails is constructed
and how rails are mounted to plate

Nice on a flat formica counter top
but twisty curvey mounted atop a 3D printer
a proper tubing frame mo better

Quote
realthor

Quote
the_digital_dentist
XY assembly on a flat steel plate (?)

This means that it will be doable only by guys with access to a machining shop to cut the plate for them right? You are talking something like this: [youtu.be] ...

Quote
the_digital_dentist
It will meet all the basic requirements for a quality printer and look a lot my current machine:

Rock solid 40mm square t slot aluminum frame
electronics in a drawer?
fully enclosed
linear guides for all linear motion
32 bit controller
DSP drivers on X and Y axes
no autotramming
high voltage supplies for motors
minimal/no printed parts- all metal

and
XY assembly on a flat steel plate (?)
bed lifted by 3 screws and 1 motor
heated bed?

print envelope: 300 x 300 x 600+ (?)

As always, print quality will be highest priority. I will control costs by using used parts wherever practical (I already have 3x Japanese linear guides from ebay and all frame parts from a scrap yard) and doing all required machining myself.

I really appreciate your last build and write-up you made on instructables.
But after I built my corexy I have a question. Are you building your corexy for speed or for precision and accuracy while printing at around 50mm/s like your last printer?
It seems that just like your last printer your corexy will not be a lightweight. This means that you could put an X axis motor on the Y-axis bearing and make your moving mass just 400 grams higher (if you use nema17). This seems more reasonable to me than building a heavyweight corexy. Unless of course you are building just because you like corexy architecture which sounds like a good enough reason to me.

I haven't decided on a target speed yet. It will depend on the masses involved and I am not at that point in the design yet. The largest moving mass will be the X axis which will likely include the extruder, but I expect that mass will be considerably lower than the Y axis in my current machine, so it may be possible to speed up printing a bit while maintaining print quality.

---

Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]