My design of a CoreXY, reasonable large format.

Hi all.

I have been thinking about this design for a while.
Now, life takes a turn, and Im about to start my own business. Some may now from earlier post.
That I work with large format 2d printing. Mainly inkjet printers. Prucing material for displays,expo ect.

So, In that case. I want to incorporate 3D printing as a solution for some projects/customers.
There is no way I can go buy a 3D printer like this now. I need to invest quite a bit in other equipment that I can not build my self.

So, I'm prepared to spend som money on a printer that is reliable.
Instead of inventing the wheel all over again. I need input on what is reasonable in the parameters I want/need.

Step one. build volume.
Im hoping of a buildvolume about 100x70cm base, hight 100cm.
I do understand that will come with a set of serious problems for precision on the bed.
Your input here?
I had a thought to have a solid cast iron, or a granit bed that is stationary. With the upper section moving I Z axis instead of the bed.
But in any case. Even balanced, its still quite a mass to move around.
If I need to go the more common route with a moving z aluminium bed. What is you're opinion?
Having a modern electronics that compensates bed warping. Will be onboard in any case. But a warped bed, is still a warped bed.

Frame will be a heavy steel construction with enclosure.
I will probably print quite alot of ABS, du to it seems to have the best longlivety in outdoor use.

Im also debating with my self to do a moving gantry with stepper attached to it. Probably not, du to the more mass.

Also, the design will be done so if I need to construct fixtures, jigs ect. I will do so. Plan is of coarse to expand and grow
3D printing services.

A moving bed on anything near that size is going to be a challenge, If you used a piece of 1/4 inch cast Aluminum, which is going to be the lightest flat thing of that size your likely to get it would weight at least 30lbs. And I haven't done the math but I suspect that a piece that long would have measurable droop in the middle unless it has some sort of support. It might well be easier to move the gantry up and down.

Assuming you can solve the mechanical issues, your going to have to heat that bed, that's a lot of thermal mass.
I've never used a heated chamber, but I'd be interested in how much of the warping problem they really solve when parts start getting that large, you might want to consider one of the polyesters instead of ABS, though they tend to have their own issues.

You also need to think through print quality, nozzle sizes, plastic consumption and print times.
Your talking about building a machine with about 90x greater build volume than most of the printers people use, if you intend to use that build volume, you're going to have to find a way to fill it a lot faster.

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My blog [3dprinterhell.blogspot.com]

Ty very much for youre response!

The big players out there. Use (what I have found out) heatchambers with advanced tmepsettings with ramping temps up and down.
I was thinking that then, a heated plate might be not neccesary? That would make bed warping musc less of a problem. Hm..
this is Intresting...

If one still would have a moving gantry. One could balance the wheight out with counterwhights.
Still ther is mass to move. But in my mind. Z movement is less critical in that case then x and y.
Im not sure Im right here. But its Intresting.

Its clearer to me now. Considering my timeframe and limited time on hands. That the above projekt will be a later version.
It hurts a bit. Going all the way on challange, is my kind of thing. But I will have to go a more standard appoach. (Still open to diskussion )

Core XY with a heated bed that moves in z.
Frame will be steel. With quality mechanical parts. Will outsorce the macshining i cant do my self.
Linearberings, ballbearings, belts, ect will be highquality parts. As electronics, steppers Ect.
Think I go for duetwifi for the board.
Have a hotend design I hope I have time to develop. But probably goes for a ready made part to save time.
X gantry will be carbonfiber. Hope to have the possibility to land a autoclave a buddy runs.
So, now is the question. How big is a big, but reasonable big bed? I have serched around alot.
A glasbed saves alot of the warping issue. But still no clear info. 50-60cm?

I've thought about large scale 3d printers, and seems mass becomes an issue when making components bigger to maintain rigidity.
IMO, CoreXY works for small/medium formats, or rectangular long Y builds (short gantry). When excess of a meter, travelling columns and gantries will not have the speeds equal to the task of a large print volume.
Belt stretch and droop (sway, and drop) is going to become a major problem in a really big CoreXY.

FWIW, the Ultimaker cross beam carriage appears to have an edge when going big. Remote drives and balanced masses FTW.
Below is an image of a dual head carriage abandoned when I decided on two independent carriages for my current WIP.
The main issue will be rod whip, though larger diameter hollow shafts (tubes) are a possible answer.

I agree with you on mass problems, when going really big.
Holow rods is a very good idea. In not sure if they are available as inventory by producers?
Ultimaker setup is genius in my mind. The crossings gives nice stability for the hotend assy. Especially if they are separated by hight,a bit.
To keep mass down. I think Bowden (as often) is the way to go.

Saw a rod grinder for sale today.. hmm..
Maby one could use hard tubes. bond karbon rods inside. then grind OD for precision.
that would give stiff rods with a good surface for bearings.

Think my shop needs a flatbed grinder too..
Mill is in the plans. But have to wait now.

FWIW
Moving big bed printer

Trinitylabs Aluminatus A1 3d printer

[www.youtube.com]

Igus sells hard anodized aluminum shafts.
The 12mm solid and 20mm hollow (2mm wall) weight about the same per meter.
Though have seen printers and routers using EMT (conduit) for shafts, MPCNC on Thingiverse for example.

Quote
cozmicray
FWIW
Moving big bed printer

Trinitylabs Aluminatus A1 3d printer

[www.youtube.com]

That is not big. I recon that is normal size.

Quote
prot0typ1cal
Igus sells hard anodized aluminum shafts.
The 12mm solid and 20mm hollow (2mm wall) weight about the same per meter.
Though have seen printers and routers using EMT (conduit) for shafts, MPCNC on Thingiverse for example.

Im not really convinced about igus bearings. Or rods in aluminium.
Im a bit old school when it comes to machining. But it might work.
If its going to be a bigger printer. Im worried that it might flex. even with very light hotend assy.
Im sure igus orks well when its under movement. But I have concerns about flex and how it performs under accelerations.
Especially in direction changes. Flex and low speed can give serious sticking problems.

How is the common experience out there?