Here is the core xe concept worked up in Rhino.

Here is the core xe concept worked up in Rhino.
The red belt is a closed loop, as is the blue belt at the rear. There is another blue belt at the front but I’ve hidden it to allow the bearing assembly in the x carriage to be visible.

I’m curious Tim, why core xy?

Whoops, typo. Should have said core xe. If you examine the mechanics you’ll see its not core xy. Check my previous post for a run down on why this is a clever idea.

I was trying to figure out why there were idles by the stepper. Now I see you would need that to engage the teeth in both the carriage and the stepper pulley. I can’t think of any way to avoid it off hand. But it would be nice to be able to dump the idlers if possible. Less bearings to fail.

@Eclsnowman Yep. It’s a tough one. Now I think about it, it would make more sense to use 2 idlers at the extruder carriage on either side of the pulley, flip the belt and get rid of the pulleys at the Nemas.

Hmmm, but that would force a wider spacing between the belts running between the linear rails…

I think keeping them on the steppers is a better solution than adding weight to the cart. CoreXE is trying to minimize carriage weight, so I think that would be a step backwards. You could use a twin belt, teeth on both sides. But I think the cost is significantly higher and less cheap Chinese suppliers to use.

http://www.gates.com/products/industrial/industrial-belts/synchronous-belts/powergrip-gt2-twin-power-belts

2 sided gt2 is, a great idea. I was looking at some earlier today but the potential for using it in this bot didn’t occur :).

Glad I could help with ideas. A blind squirrel finds a nut every once and a while. Guess today was my day :slight_smile:

Any reason not to simply put a half twist in the belt between the motor and the carriage? Then you might not need any extra idler pulleys.

@Michael_Hohensee it would be problematic as things approach the edge or travel.

Ah, good point, @Eclsnowman . It might still be doable if the twist is between the motors and the y carriage, and if the motors are positioned far enough outside the ends of the y carriage’s travel to support it. Maybe going outside the frame would be a sufficient distance… Looking forward to seeing @Tim_Rastall 's calculations. :slight_smile:

You could use synchromesh.

@Eclsnowman Yes, true. Except I’m not certain if you can get closed loops of it and I have a feeling the minimum pulley size could be too large. I suppose I should go check.

Hey Tim, I’m posting this here as I can’t really find anywhere else to ask you questions :wink:
I was asking over in the questions section about which printer would be good for my first one, and “Jeremy G” directed me here, but I can’t seem to find any laid-out designs around here where I can just go to some website, put some stuff in my cart, and then follow some dirrections once they arrive. Do you offer and cut-and-dried designs like that for a beginner looking for a straight-up build? And if so, where?

Thanks ;D

um, Not quite sure what all you meant, but I’m not asking for any sort of guarantee, I’m very used to the “I broke it, so I fix it” side of DIY, I’m just asking if tim compiled a more thorough guide for his creations in line with the things you find on instructables, or if I’d be on my own if I tried to figure out how he built them, that’s all. Here’s the exact response I got over on my thread that made me think he may have some instructions laid out somewhere:
(Jeremy G)
"… dont do makibox they ran out of funding as far as i know. if you like to build. +Tim Rastall printer looks nice. you could inclose that printer fairly easy.

+Richard Horne’s 3DR is a nice delta bot you could also inclose.

+Brook Drumm has a nice line of printers you could build a case for and are fairly quiet.

I3’s are nice."

@Eric_I core xe is a non-tested design idea. No one has made one yet. Not a good starter design unless you have some real ambition.

Tims Ingentis, or Jason Smiths Eustathios would be a better starting point.

If you want something documented better than any other DIY try the prusa i3. Or perhaps a lulzbot.

@Eric_I I’ve sent you an invite to the community we’ve started for the Eustathios and Ingentis builds. Eustathios is the latest generation and has a complete bill of materials. No build guides yet though.