Corexy vs cartesian for HQ, slow printing

I have been printing happily with my prusa i3 for years and a few weeks ago decided to build a new printer. Quickly I decided to go with corexy as designs were stiff (inside a cube of 2020 profiles) and build costs were reported to be reasonable. I am now mid- way finishing it. However I am having some second thoughts wherever corexy is a right type printer for me.
Here is what I want from the printer:
- 0.2mm layer height
- direct extruder mounted on X carriage for perfect retraction
- I am fine with 30mm/s print speed in order to get a good quality prints
- high repeatability in XY plane

It seems that corexy was designed with fast speeds in mind. I wonder if those metres of belts in XY plane might make repeatability suffer. I am thinking now that what I should have built is a cartesian printer built inside a cube of 2020 profiles.
I know there are people here who have been having some stiff cartesian printers and have moved to corexy so your comparison would be helpful.

Edited 1 time(s). Last edit at 10/13/2015 03:19AM by Edvardas.

I have an prusa i3 all aluminium and an corexy printer.
My prusa was a good aluminium struture and is well tuned, but the corexy printer was far better print quality.
The cartesian printer was several problems that the corexy do not have, from all the design i have see for me the corexy is the best so far.

With the prusa i must print at 50 to get an good print quality, with the corexy i printing at 80 amd still getting better prints.

You can get an very rigid struture for an cartesian, but i still have the elefant in the room, the bed moving in the y...

I have both Cartesian and Delta, and I prefer Delta. I haven't tried CoreXY yet, but I think it would be my choice for a larger printer.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Repeatability should be fine if your belts are properly tensioned and the printer isn't unreasonably large. Even at low speeds, the low weight of the CoreXY print head reduces the presence of ringing patterns in prints.

BTW, I run a bowden e3d lite6 on my printer, and I've gotten it to have virtually no stringing by changing retraction settings.

Quote
AlexY
Repeatability should be fine if your belts are properly tensioned and the printer isn't unreasonably large. Even at low speeds, the low weight of the CoreXY print head reduces the presence of ringing patterns in prints.

BTW, I run a bowden e3d lite6 on my printer, and I've gotten it to have virtually no stringing by changing retraction settings.

I am actually putting e3d lite6 nozzle (which can easily be upgraded to bowden) on a new printer. What materials do you print? I would probably have no problem going to bowden if I printed ABS or PLA but I had a hard time controlling ooze on my direct drive extruder using PETG so it would be a hell trying to control it on a bowden (unless where is some magic in e3d compared to my old J-head).

Hi guys,

IMHO the Lite6 does not matches with high temperature materials
like ABS and PETG because of the teflon tubing.

Don't worry about the belts, just use the right type for the right machine.
I drive a big CNC mill with belts, with a pretty good repeatability,
even if the gantry weights more than 100kg (220 lbs).
Just check that GT2 belts are enough for torque and speed.

Repeatability is mostly a question of build quality and setup.
CoreXY is probably (one of) the best architecture for 3d printing.

Even if you install a direct drive feeder, 30mm.s is very slow for a CoreXY printer.
I'm a bowden enthousiast. I believe you can print pretty well with a bowden system.
You just want to drive the filament properly from start to end.

++JM

E3D states the max temperature of the lite6 to be 245ºC which should be adequate for both of those filaments.
For oozing, the lite6 could possibly be better than the j-head since the PTFE reaches from the extruder to the tip of the nozzle. This might reduce the chance of the filament from bending before it gets to the hotend and affecting extrusion accuracy. Another consequence of the PTFE tubing all the way to the nozzle is that you can run much longer retraction lengths without causing jams.

Hi J

I am designing a CoreXY machine right now. The belt I am going to use is 10mm GT2.
The foot print of the XY plan is about 1000mmx600mm. Do you think 10mm is enough?

Thanks

Paul

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Printer I bought: 2015 Sunhokey Prusa i3
Printer I am designing: Another big CoreXY machine

Guys... Please if possible can someone share a CoreXY plan...

Look at the digital dentists topic. It contained enough pictures and information to work as a plan. I am building one now using his topic as a design.

You might also want to look at the RailCore II, [www.thingiverse.com].

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].