Time and Resolution

I was discussing ways of making better prints with a guy in my office. What follows is the result of that discussion.

A big problem for 3D printing is that you have to trade resolution and time. If you want a cleaner and more accurate part you have to wait longer for it. This is because the printers can’t cover a large area at once. Whatever method is used for the smallest areas has to be used for the largest ones. Maybe you can change tools, but that’s got issues.

Wouldn’t it be nice to be able to form an entire layer at once? Yes. Yes it would. Here is a theoretical method for doing that.

Start with a build surface. Fill that build surface with a grid of tiny holes and in between those holes put tiny electromagnets. Next, flip that surface upside down so that the electromagnets are on the bottom. Now when you inject ferrofluid through the holes you can move it around on the underside of the build surface with the electromagnets. By turning the electromagnets on in a controlled order you can arrange the ferrofluid so that it outlines the exact shape of your first layer.

Now put that into a tank so that the bottom of the ferrofluid, which is hanging off of the build surface, is just touching the bottom of the tank.

Inject the printing substance through the build surface into the cavities formed by the ferrofluid. Even if the substance is liquid, it will be constrained by the floor of the tank and the ferrofluid.

Harden the printing substance in some way. Heat, UV light, catalyst…kind words. Whatever works. Then raise the build surface by one layer height. Fill the tank with enough of a support substance to just reach the depth of one layer height. This support substance needs to be denser than the printing substance.

Inject more printing substance through the build surface surface to fill the cavity formed by the ferrofluid and the previously hardened printing substance. Any overhangs will rest on the support substance.

Repeat this procedure for each layer, rearranging the ferrofluid when necessary.

This process, or something similar, could open up a paradigm in which you don’t have to trade time and resolution. Each area of detail can be resolved at the same time by just controlling all the relevant electromagnets, then the open space can simply be filled with whatever it is you’re using to print. It doesn’t seem like the control electronics would be all that complicated, either. Basically you’re just drawing on an LCD readout. The complicated part of this idea is the various substances. It’s more of a chemistry problem than an electrical problem.

Insane 3D Print Resolution

You know how professional 3D printers start at $10,000 and then work their way up to $100,000 or more? Yeah…that’s probably going to change soon.

Dave Durant posted a long series of examples of how the latest generation of open-source 3D printer software and hardware is quickly outstripping our ability to challenge it. His post is well worth reading through, so I’m just going to highlight one point.

He linked to this post in which Jordan Miller put one of the newest Ultimaker prints under a microscope.

That thing on the left, kind of hard to identify…that’s a finger. Or, rather, those are the little ridges that make a fingerprint. Yeah. The average layer height in that print is 0.074mm (74 microns).

I just want to remind the reader that resolution was achieved on a printer that’s not only around $1600 but also open-source, so the software and hardware designs are available for free.

Dave has another example of a print by Paul Candler that uses 0.02mm (20 microns) layers (two perimeter layers for each infill layer). For comparison, the Stratasys UPrint can do 0.25 or 0.33mm. It costs $20,000.

If you want an Ultimaker (you should by now) you can even win one for free.