Carbon 3D

[hegykc]

"Fabrication of a ring structure:

ball screw moving at a continuous rate of 20 microns per second and successive exposures were carried every 10 microns along the building height at a duration of 0.5 seconds per exposure. The total number of successive exposures was 1040 and the total fabrication time was 520 seconds."
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See, there's no continuous image projection. The patent even says they use Slic3r. Only the z axis is moving continuously, but there are still individual image slices projected from the dlp projector.
No additional software needed, you just don't turn the projection off ever, because there is practically no "large" up/down movement of the z axis.

You could just set up CW with 0.05mm lift and 0.05mm layer thickness (no retract), and xy seconds projection sequence, and would get what looks like a continuous printing.

[pizzaslice]

Info for making Teflon AF sheet:
http://www2.dupont.com/KIV/zh_CN/assets ... H44015.pdf

Research quantities of Teflon® AF resin in solution come in 100 mL packages, see
http://www2.dupont.com/Teflon_Industria ... _home.html
Price per package varies from 250 dollar, 1000, 2800 dollar. Solid loading is 1 %, 6% and 18%.
100 ml bottle equals 100 cm3.
Volume of a layer, you would typically use 20x30x0,0065 cm= 3.9 cm3
So you will need 3.9 bottles of 250 dollar = 1000 dollar.
From a bottle of 2800 dollar, with a solid loading of 18 percent, you can get four sheets, so 700 dollar per sheet.

[hegykc]

This is all fascinating.

If the Z axis only needs continuous motion, you don't even need a printer brain like the arduino/ramps combo. Heck, you don't even need a stepper motor. Nor the ballscrew or expensive linear slides.. theres no force for separation remember?

Only an electric motor geared to the 20 microns per second speed, or so,attached to a dirt cheap threaded rod and a switch that would turn on everything at the same time. So UV leds, CW and the electric motor, everything switched on at the same time and that's it.
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Ok this thing is pure magic:


"Teflon® AF possesses outstanding optical clarity and transmission. As Figure 2 demonstrates, Teflon® AF has outstanding light transmission from the deep UV range out through and including a significant portion of the IR range. Also, because it does not absorb light, Teflon® AF will not deteriorate with exposure to light. These optical properties, over such a wide range of wavelength and possible exposure conditions, are unmatched by any other plastic."

So, it comes in liquid form straight from Dupont. Since it's 1.800$ for 25 grams, it might be cheaper to get already made sheets, like from Biogeneral there, as they probably buy tons of this stuff.
I'm looking for density info so I can calculate how expensive a 100 micron sheet would be per cm2, if I make my own sheet.

[pizzaslice]

Synonym: PTFE AF 2400 PTFE AF, PTFE® AF
density : .67 g/mL at 25 °C
more info http://www.sigmaaldrich.com/catalog/pro ... &region=NL
price per gram: 374.50 dollar per gram, shipping date 28.05.15, gold is like above 1000 dollars per gram

[hegykc]

Thanks.

So, 1.50$ per square inch for DIY 50 micron thick sheet, according to Dupont prices of 72$ per gram for the liquid form. Or about 500$ for a sheet to cover a 15" lcd screen, 250$ if you go 25 micron thickness. That's not bad actually if you need big objects printed at fast speeds.

I guess you could mold it by putting a few drops between glass sheets and then squeezing them with a separator of a known thickness in between, like a 50 micron foil/sheet of any sort on the edges of the glass. And putting in in the oven.

Even at this prices, this thing would simply the printer design quite a bit. No release force mans no need for expensive metal parts. The whole printer construction could be laser cut out of thin acrylic. I mean you see the magnified surface quality in the picture, it's amazing compared to the layered surface finish we have now.

[Phife]

This is awesome tech.. Gotta get that stuff for my vat. Ive been dreaming of continuous prints for a long time now. Im gonna look into it as well.

[hegykc]

This could really turn out to be the holly grail of 3d printing. And it's simple to DIY.

Continuous Z axis and 10 micron 0.5s layers. And you can go beyond that! That would mean "injection molded like" perfect surface finish.

We gotta get our hands on some of that Teflon AF goodness asap!

[Phife]

Spoke with Biogeneral, they only sell 3" wide by continuous length rolls. And its expensive. Still waiting to hear back from the other suppliers.

[pizzaslice]

Phife can you give a more detailed estimate based on your inquiry!? I am curious.

[Hugues]

if the minimum order qty is huge amount of money, let's start a small kickstarter project so we can all pledge the money to buy this heavenly film !
count me in.