Let me know if this is too off topic or not:  I was thinking

Let me know if this is too off topic or not:

I was thinking about the NASA space wrench today and one thing that I never thought of before was the fact that the wrench was in fact printed in space.

Having said this I began to wonder how important support material really would be, or rather if it would be at all necessary if lets say I threw a Reprap into space and had it print crazy overhangs with zero support.

Am I the only one who has thought about this?

Nope not alone. Also thought it could affect printing. The overhang between the ratchet and the body is very narrow.
That said the wrench prints fine on my machine I’ve printed maybe 7 or 8 of them with different filament to check. It’s one on the hardest prints I’ve had to get right but also the most rewarding. If that wrench printed working 1st time on the nasa printer it’s either down to the printer being spectacularly good or printing in space allowing endless bridges.

Gravity has little to no effect on the need for support. The main reason overhangs fail is the molten plastic coming out the nozzle pushing the strand away, but gravity. Try an extreme overhang with your machine upside down, it won’t improve that much.

The MadeInSpace machine did a few things: add fans to fix a lack of convective cooling, make the whole affair launch proof (high Gs), and make it very light. Plus add a box for trash containment in zero g.

I see your point the nozzle pushing out filament would push it down to the buildplate. So it would be similar to how it works on earth. I Never considered that, good thing in no rocket scientist. That means if I turned my printer on it side it should still print the same.

I think the only way to figure this out without pure speculation is to ask an astronaut who has used it or ask Made In Space

Thanks for tagging them @Branden_Coates

They did an overhang test on the space station: https://d262ilb51hltx0.cloudfront.net/max/2000/1*KMyAU2Ucdh5lL98o1IzKwQ.jpeg

More here: https://medium.com/@MadeInSpace/3d-printing-in-space-the-end-of-the-beginning-561f0c384983

Thanks @Mike_Kelly_Mike_Make that’s really helpful. So from the picture it looks like there was issues with overhangs but not nearly as much as in normal gravity. It looked like the bottom layer both drooped and pulled up and the successive layers pulled up slightly like @Mark_Rehorst predicted. This is ABS after all.

Wow, that overhang test looks way better than I expected. I was basing my claims on a conversation with a MadeInSpace engineer at MakerCon before they had done in-orbit tests. Wonder how overhangs do if you put an earth-bound machine upside down… @Nicholas_Seward weren’t you always putting your machines on their sides and such?

@Nick_Parker Back when the Made In Space machine was announced I saw several youtube videos of people printing upside down or on the side and the difference was minimal.

If you print upside down the overhang can get fouled by the nozzle. Sideways is the way to go. (Strand parallel to gravity.) However, it can be a minimal gain compared to a well tuned normal printer.

Check out this article on the subject: http://3dprint.com/87416/3d-printing-space-supports