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Show HN: 3D print Z reinforcement via injected loops

mgunlogson.github.io

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Re: Show HN: 3D print Z reinforcement via injected loops

#51

Post by mgunlogson »

warumdarum wrote: post #21
Aurornis wrote: post #10

Interlocking layers is an interesting idea, but I don't see how this is supposed to work. You can't use the nozzle to inject that much filament into a large cavity because it will cool and solidify right out of the nozzle. Anyone who has ever cleaned blobs of filament off of a nozzle after a print failure can tell you what happens when you try to pump hot filament into empty space. Filament cools below the melt tempe…

Secondary epoxxy nuzzle?

Resin would be very interesting. The tube design seals them everywhere below the top layer. And the two ends of the tube tops are always at the same Z.

You could technically inject anything liquid enough into the tubes. Grout, resin, glue, silicone.

Re: Show HN: 3D print Z reinforcement via injected loops

#52

Post by mgunlogson »

slabity wrote: post #7

I've seen this technique a lot, but mostly as a post-processing technique where resin, fiber, or some other type of plastic is injected into the channels after printing is completed. It would be interesting to see this done during the normal printing process. I am a little skeptical on the technique though. FDM printed walls are known to not handle pressure well, especially during printing when its past its glass-tra…

> Will this pressure could cause the walls to delaminate from each other or deform?

Nobody knows :) . Give it a try!

> You're also parking the nozzle at the injection points, which will cause a lot of uneven cooling at the surface as well.

There's an "injection fan speed" setting that should probably be kept at 100%.

I'm not sure the "not have any cooling" will be a problem in practice. Because unlike normal printing you're not concentrating all the heat on one layer. It's going down Z dozens-hundreds of layers to already cooled areas of the part printed minutes ago. And the design tries to avoid having nearby tubes end on the same Z. So the area directly adjacent to the tube has probably been cooling for a while.

> So I guess the underlying question should be, does this actually work? What is the measured difference in tension strength between parts printed normally vs with MAGMA infills? Specifically when using the same amount of plastic. There's no data or even pictures that indicate this is working.

No one knows. And I can't test it anymore. The code is done and I have other projects to work on. I've done probably a hundred test prints on my POS Ender 3. I need testers with better hardware. No matter what I try the top of the cell gets melty. This could be the low flow rate of my hotend (limits injection speed), the fairly bad cooling, or maybe something fancier like dual material is needed. Or maybe I just haven't landed on a good combination of settings since there's dozens of them.

I particularly want someone with dual nozzle to test so they can try injecting a low melting plastic like PLA into a heat resistant shell like CF-Nylon or more exotic materials. There's printer plastics that aren't even at glass transition temp when PLA is at printing temperature.

I added dual nozzle and multi material support. Obviously hasn't been tested though

Re: Show HN: 3D print Z reinforcement via injected loops

#53

Post by mgunlogson »

dwallin wrote: post #5

Instead of one large channel throughout the whole print, why not multiple small 2-4 layer bridges?

You can set the tube height to like 4mm and that's pretty much what you'll get.

The tubes only need to be tall enough for a "window" at the bottom and a splitter in the middle so that plastic will flow up one side and down the other.

The window height calculations are automatic right now. To make sure the window area is as large as the tubes so it doesn't create a bottleneck that stops flow.

But if you print tiny tubes with a tiny nozzle you could probably get the tube height down to ~3mm.

There's binaries if you want to play with the settings and see it for yourself

Re: Show HN: 3D print Z reinforcement via injected loops

#54

Post by mgunlogson »

kamranjon wrote: post #41

I do quite a bit of 3d printing of functional parts and am trying to understand how this would fundamentally differ from printing at 100% infill? What type of part requirements are causing failures when something is just solid? Just curious what problem space this is targeting?

Z layer weakness is the main reason that 3d printed parts are brittle and much weaker than injected molded ones.

This is meant to knit together the part in the Z axis

Re: Show HN: 3D print Z reinforcement via injected loops

#55

Post by mgunlogson »

coryrc wrote: post #6

Why do you think this is better than the old practice of filling straight holes a few layers deep?

because the plastic has to displace air.

This method seals the nozzle against the tube and injects under pressure (theoretically). And leaves a path for air to escape. Pretty much a micro version of injection molding

Re: Show HN: 3D print Z reinforcement via injected loops

#56

Post by mgunlogson »

lambdaone wrote: post #33

This re-thinks the entire 3D printing paradigm. Whether this specific idea works or not, I'm sure that this will lead 3D printing research in interesting directions - and the defensive publication is a massive help.

Thank you!

A lot of people here took issue with the crappy docs. My mistake, I barely spent any time on them.

The reason this "came out of nowhere" is because I was working on it in secret for a long time. So that patent trolls couldn't screw the 3DP community yet again.

Re: Show HN: 3D print Z reinforcement via injected loops

#57

Post by mgunlogson »

smallpipe wrote: post #13
mgunlogson wrote: post #4

Earlier quoted context omitted.

No, unfortunately. I've printed a ton of objects but nothing clean enough to be interesting. The top of cells always melt as I'm using the same material for injection and the rest of the print. Someone with a dual nozzle printer could try something like PLA injection in a polycarbonate part. I added support but don't have a printer capable of that. It's also possible that different print settings would work. I'm rele…

I’m surprised you bothered writing software instead of writing some G code by hand for testing

Because that's not accessible.

IMO the reason other efforts to achieve similar Z reinforcement have gone nowhere is because it was one guy fiddling with G-Code. All the big innovations in 3DP have been community projects. Now anyone can download my binaries and try it.

I'm personally very convinced this will work. That's why I did it. We just need to figure out the right settings. Maybe use a different material for injection or coat the nozzle in something.

We'll see. There's a long history of crazy ideas and cold receptions. We even have famous examples from this site https://news.ycombinator.com/item?id=9224

Either I'll end up wrong, and this will fade into obscurity. Or it will turn out I was right and a lot of people will read this comment someday.

Re: Show HN: 3D print Z reinforcement via injected loops

#58

Post by mgunlogson »

deckar01 wrote: post #8

When you say continuous interlocking U shape, are you saying it fills one channel from the top until the connected channel fills from the bottom?

Yes. It's a modified triangle infill pattern.

A solver pairs the triangle with one of its neighbors. Then cuts a window at the bottom during the slice. So plastic gets injected into the top of a triangle tube and flows through the window at the bottom of the U to its neighbor cell.

Download the binaries and try slicing with magma infill type. Turn off visibility of all the other line types and you'll see how it works

Re: Show HN: 3D print Z reinforcement via injected loops

#59

Post by alterom »

bartvk wrote: post #24
alterom wrote: post #12

>What’s NOT yet working: the physical print So, nothing to show. Next.

From the Guidelines (link at bottom of each page): "Please don't post shallow dismissals, especially of other people's work". Personally, I think it's an interesting experiment. If my prints break, it's at the layer lines. This work may be a stepping stone, an easy way to reinforce prints.

>Please don't post shallow dismissals, especially of other people's work".

That's the thing about this idea. It doesn't work.

The title is misleading too. No actual 3D prints have been reinforced.

If the title said "an idea", making it clear that is not anything that has ever worked for anyone yet, it'd be a different matter.

>If my prints break, it's at the layer lines

Then print with 100% infill.

>This work may be a stepping stone, an easy way to reinforce prints

Printing with more infill is an easy way to reinforce prints.

Orienting your piece well on the build plate to take advantage of the anisotropy goes a long way too.

This problem already has an easy solution, and that's before you get into the more complicated ones (like nonplanar extrusion).

This is idea isn't solving the problem of prints being weak in general. It's an idea about (potentially, maybe, if someone else makes it work, if it's even possible ) saving material and printing time.

It wouldn't give you prints that are stronger than those printed with 100% infill even if worked.

Re: Show HN: 3D print Z reinforcement via injected loops

#60

Post by mgunlogson »

alterom wrote: post #59
bartvk wrote: post #24

Earlier quoted context omitted.

From the Guidelines (link at bottom of each page): "Please don't post shallow dismissals, especially of other people's work". Personally, I think it's an interesting experiment. If my prints break, it's at the layer lines. This work may be a stepping stone, an easy way to reinforce prints.

>Please don't post shallow dismissals, especially of other people's work". That's the thing about this idea. It doesn't work . The title is misleading too. No actual 3D prints have been reinforced. If the title said "an idea", making it clear that is not anything that has ever worked for anyone yet , it'd be a different matter. >If my prints break, it's at the layer lines Then print with 100% infill. >This work may b…

It does work. Just not very well. Not enough to be widely usable.

If it was an idea it wouldn't have thousands of lines of code and working binaries.

100% infill doesn't remotely solve the problem I'm referring to. I'd ask you not jump to conclusions if you aren't experienced with 3D printing.

Printing 100% infill also wastes a ton of time and material on the interior of the part for nothing. I added a "dual infill shell" feature where you can use a light, fast infill for the interior of the part.

> It wouldn't give you prints that are stronger than those printed with 100% infill even if worked.

This is very speculative and I doubt accurate. Even 100% infill parts are 10X more brittle than injection molded ones and around half the strength. All because of z layer bonding weakness

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