Mimimum width, length, and thickness of objects that can be 3D printed successfully?

[jeffmorris]

If I want to create a 1/48th scale model of a subway car, what are the mimimum width, length, and thickness of objects like window frames that can be 3D printed successfully?

http://www.nycsubway.org/wiki/R-27_-...ar,_1960-1961)

[LambdaFF]

Did you mean for FDM or SLA ?

Go to shapeways and look at their design recommendations for each material / process.

It'll give you a fair idea of what the minimum industrial standard is, and with your desktop machine you should take much more for it to work.

[Marm]

Depends on the printer really.

My POS Davinci, I try to stay at 1mm increments for measurements, but I can notice (for press fit items for instance) a difference if I change a dimension by .125 mm.

Not having done the math on your model, but eyeballing it down to ~1' long (That alone will require a sizable printer, bigger than your average machine), I'd guess that window frames would be doable. Given the complexity of making this a single piece, You'd probably want to cut it up into smaller parts and print them, making support removal easier, and gluing it together. That'd let you use a cheaper/more available printer.

But to be honest, you're not asking the right question. In this case, the window frame would be printed as part of the bigger module, so there really isn't a minimum, just what can the printer do, and can you notice it. The question is, how do I make the model to express the window frames the way I want them too.

[jeffmorris]

I changed the 3D model to get bigger window frames but I can't get Simplify3D to generate supports under the window frames which are off the build platform by about 1mm. I placed the wall with window frames flat on the build platform. Without supports, my PowerSpec Ultra 3D (FlashForge Creator clone) made a mess out of the window frames. The subway car has to be 3D printed in several sections.

[curious aardvark]

the frames should print in situ - not that big a gap to bridge. So I'd keep the windows vertical and just sand off the first layer, as that'll be a bit wonky.

As far a sminimum size goes.
I can print things that are one layer thick. and 0.4mm wide (a single bead)
There's not much point. smallest thing I've printed recently was a piece of tubing out of polyflex. 0.8mm walls two beads), 6 mm high and about 6mm across.

Used it to join two pieces of thin plastic rod that had broken.

[jeffmorris]

Nycta-R27-walls.stl

Here's the 3D model of the subway car wall.

[curious aardvark]

is that file in inches or millimetres ?

is it supposed to be 2.69x1.56x0.12 mm ?

In which case - it's way too small to print.

Look at it this way it would be 0.12 mm thick. You couldn't get it off the bed without breaking it to start with.

For that you need a decent sla machne.

Actually it should at least make the square and all I get is a horseshoe shape.
So how did yu make the stl ? I reckon there's problems with it.

Though s3d does say it's 100% manifold.
weird

[jeffmorris]

The file is in inches. Scale it up 25.4. I used AutoCAD to create the 3D model and exported it to STL file.