100% infill vs max number of walls (or perimeters or shells) - which is stronger for solid object? 

I love when the algorithm shows me some smaller channels, hopefully you can grow, the testing is very well done and you deserve more views

My solution is 10 wall/10top layers/10bottom layers and 100% infill. From my experiences it gives me the best results. Thanks for the video and keep up the good work!

What always surprise me, is how strong 3d printed parts can be in certain applications and orientations, it makes 3d print fun for one like me that likes to print rc stuff and train parts for my model trains

Great set of tests, and thanks for also including Stefan’s data about strength as a function of wall vs infill. Great work!

So a downward hook, infill. An outward hook, wall. Stretch vs bend benefits. Fascinating. I wonder how it would differ when combining the two in varied amounts. For instance if a total wall number that can max be is 10 layers, doing 1 wall layer with 100% fill, and going up 2, 3, 4, 5, 6, 7, 8, 9, and full wall no infill, to see if there is a sweetspot where it gives better result from it over full infill vs full wall.

This was pretty interesting. You have tested the two extremes (Max walls vs max infill) but It would be also nice to see how lets say 10 walls + 100% perform.

Great video - I've been wondering about this for months (but never got around to actually testing it) and now I know. Thanks!

I think some benefits can come from the alternating angle of the infill. But I often print max walls, because it’s not shaking the printer in small areas like the zig zag. Also - but this depends on how good your printer is tuned - sometimes a lot of infill can build up more overextrusion, because of linear advanced, overlaps etc. My petg prints are often a bit cleaner with max walls. Great content as always!

Thank you very interesting. I would also have guessed that the max walls would win, exspecialy for the tensile test because the walls are orientated parallel to the tension while the infill is at an 45 degree angle to it.

Nice test! Thanks for sharing!

You speak English very well. It was easy to understand what you were saying. Thank you for this helpful video!

Truly you doing one of the best tests. Wish you have good luck.

Great testing!

Thanks once again Igor. You save us mere mortals a lot of time and effort by running these test.

Great test, just what I was looking for to help me decide before making final prints more solid , great work, thank you very much

Wow that was a clear explaination ! thank you !

it makes sense that 100% infil parts are stronger as the layer "criss cross" so to speak so there is more surface area for it to grab onto. With multiple walls its laying down on top of the same pattern each time so the surface contact patch would be smaller.

Fantastic analysis!!

Always fun to watch and good information.

Nice Work, thx vor uploading.

Great test, very interesting Thanks for sharing your experiences with all of us :-)

Great test! Interesting channel, subscribed!

Very informative!

These results are interesting. For my prints requiring different strengths, such as a 3d printed electric guitar, the guitar string tension would then need maximum walls down the spine, but everywhere else use maximum infill.

If you're just testing, it's good for my wallet. If there is a product review in your video, I almost always know I will be ordering. Good job. Thank you, greetings from Slovakia.

great tests. This confirms my long held suspicion that with 100% parts, infill is the way to go. Usually, my hesitancy comes from the fact that walls are only bonded on two sides, really (since the material directly underneath doesn't add much support in this failure axis), and those bonds are the weakest parts. As a part fails, the failure typically occurs between two walls, and can then "zip" down between the walls. For this reason I call it "zipper failure". The crosshatched nature of (rectilinear) infill inherently prevents zipper failure, as the break is not allowed to continue along the line bonds unimpeded, it has to break completed lines across the line bonds. It looks like on the infill specimens, there was a bit of a gap between each line. If we consider that the increase in strength from infill is a continuous line (% infill vs part strength), and that increasing walls and increasing infill reach similar ultimate strength, coupling that with stefan's infill vs walls testing would mean that the last few gaps that remain during infill printing are very detrimental to the overall strength (the last few % of infill give more strength per % than previous). Therefore, I think the inclusion of air in the 100% infill part due to slight underextrusion can significantly impact the strength characteristics. It would be interesting if you could tune your extrusion so that the infill portions are truly gapless (it's not easy to do), and do another test with 100% infill, 99%, etc down to about 90%. I think there would be enough data to find the curve where the strength starts increasing more and more with those final few %.

Great video Igor, many thanks! This here mech engineer is also surprised by the results, but I think your explanation attempt sounds both reasonable and logical.

A development since this video is variable width extrusion, up to about 150% of nozzle diameter. Useful for both faster printing without needing a larger nozzle, and where a wider wall better fits a narrow part. This should allow the max walls option to closer approach 100% infill.

Nice video. At fist I thought that max walls will aboslutely crash max infill. I think that when using max walls, the lines exacly in top of each other play a mayor role, and also, in max infill the lines corresponds with the direction of max shear stress. Not enough specimens for a conclusive statetment but very interesting theme. Greetings from Argentina

Excellent topic. I print a lot of structural/load-bearing parts, and your experiments have been very helpful in optimizing slicer settings (and material choice). Keep up the great work.

On the mass difference - with infill, there's overlap with the walls so perhaps that contributes to the higher mass?

I would definitely like a test of optimizing the models so that the walls have perfect spacing as the infill will auto fill this. This way we have no weak points inside of the print. Another interesting thought is 100% line infill, but in the direction of the part. Will it work even better than walls due to the higher amount of going over itself (30% usually)

Thanks!!!

Infill has 30% overlap with walls in Cura by default. Make it stronger by increasing the overlap.

I'm guessing infill is stronger because of the alternating direction of layers giving a ply wood affect of alternating grain structure. I wish you could alternate between the max infill and max wall option each layer

Would've been cool to see a version of the specimens with 4 or more than 2 walls with 100% infill to see if a mix is even better than walls or just infill. Good video regardless.

100% infill had more material, causing cross-sectional area to increase slightly, making the part stronger. The difference in mass is about 3.7%, and your numbers show that infill is about 3-10% stronger, except for the impact test. Even considering the mass, it does seem 100% infill is slightly stronger which makes sense considering the lines cross, making the part stronger. I think the most fair way would be to check the material mass used in the slicer, and make sure they are equal before doing the test.

I was near sure, that the full wall prints would be stronger.... Interesting, even if the differences are not so big.

i love the questions you ask, love your channel. Thanks for this. Btw, concentric lines for infill would be the same no?

I thought the wall would be stronger too. Intresting. Great tests and video

good video :)

Velcome to znz kitchen. Love it. Keep it up!

I really like the clear way you Display the data. It could be a bit bigger, maybe even full screen, it's a bit hard to read on a tablet or a smaller laptop. Or maybe I just need to get some glasses. Anyway, nice work. Keep it up!

Thru trial and error I found that for load and torsion bearing prints a 4mm thick wall and solid infill is the best way to go.

You should try slicing with Cura Arachne engine (still in beta) - it can vary wall widths to completely fill the space.

Infill also typically has some overlap with the interior perimeter, I would guess that is why there is the weight difference.

The more 3D printing test videos I watch, the more I realize that the best method is to just print everything normally. Normal PLA is a good material. If your part fails, you need to design it better. There's no magic trick to make things stronger.

Suggestion: would you make the text bigger so that one can see them at 144p resolution? Some of us have to live with low bandwidth connection and can't see such small text. Thanks.

Great video, me liked. I only have one thing, it would be great if we saw super closup on the breaking cross sections, possibly even in a controlled environment and only a photo, not a video. Just an idea. Thanks for great content, i like it very much. I am learning a lot for the time when i have my own 3d printer :D

I doubt the higher weight is from the closing line. More likely is, that your infill is printed with a 30% overlap (default in CURA) with the walls. Needs a little more Filament due to the overlap.

Would love to see more close ups of cross sections in different directions ( longitudinal/latitudinal)

I know it would be hard to do, but it would be cool to see this test done again with actual moulded plastic parts. I bet a part that is injection moulded weighs more than any 3d printed version will, even with 100% infill.

Comment on the first hook test. I calculate medium strength per gramm: Wall 5685.5/91.6=62KGperG; Inf 5897.5/96.3=61KGperG (decimals truncated). For small item perimeters fat has significancy.

I've seen 100 times in groups that "walls are better". Based on this info I've come to 2 conclusions. 1) it doesn't really matter as they are more or less the same. 2) infill is faster so why slow it down with perimeters? So 100% infill it is for the rare cases I need it.

Have you ever tested using different infill line angles? Select 100% infill and set it so that each layer has lines that are perpendicular to each other or other angles like 0,45,90,135. I'm curious if it makes a difference. Great stuff as always!

My personal experience with printing PLA is lower the fan speed. Find that sweet spot where the PLA still prints good with the lowest fan settings. The filament will layout hotter and stay hotter longer creating a stronger bond within the layers.

What speed are you printing the walls at vs the infill? also how much "stepover" on the infil into the outer shell?

Very interesting test as usual. What I wonder though, is there a difference between parts printed all at once, or parts printed one by one so the part does not cool down as much between layers

In my maker's view, you should have used in infill designed for mechanical strength. In your test, you used the "lines" infill, which is well known to be suitable for decorative pieces, not mechanical parts. For example, in Cura I only use the Cubic infill for mechanical parts and do not use Line infill (as you did) because Cubic infill is much stronger for functional parts. Hope this helps.

Again: such a great idea and test! You mentioned CNC Kitchen, it would be nice if you could link the videos of him. E.g. 11:26 Infill vs Shells I would like to see (without searching :)

Also note that infinite perimeters will limit the x/y-resolution to 0.4 mm increments which can be a problem if you need dimensionally correct prints.

I thought for sure the wall would be stronger.. So... I learned somthing.. But wall is better for flexing situations.

The print time for max amount perimeters was 3,5 hours. What was the print time for the one infill? Because if it was printed slower, that could have made it stronger. Slower printing means more bonding between layers!

07:13 It would be good to have tables and other detailed text full-frame for those of us watching on our phones, propped-up on a stand rather than directly in front of our faces.

Sir, the 100% infill pieces were ever so sligthly heavier, thus denser. Can you explain difference in strengt by differenc in density?

What about all tops and bottoms, any difference from those 2 mentioned?

You know that there is 12 different types of Infill patterns listed in Cura. Time to see which infill is strongest. What infill pattern did you use for this testing? My research says that Triangle pattern is the strongest pattern to use. Awesome vid appreciate taking time to show all the results you've come up with.

How about the printer motions. I think shakey infil isn't has nice as long walls/infil. I also thought walls would be clearly stronger, I was wrong.

I'm not normally one to ask about speed but since the difference was so minimal I have to ask... What method was faster to print? It would matter if you needed to rapid prototype a part for mechanical purposes 😉

Nice test. Isn't the difference is the pattern only? Concentric infill should near the same(look) I think. Maybe an ironing top layer give some very small strength.

PROJECT FARM FOR 3D PRINTING!!

so what patterns are strongest at 100 percent infill? does it make a difference?

Wonder if with Arachne the walls will hold better now.

I have massive doubts about that device you're using with half a second refresh rate. During that half of second, there could be higher values, so it's pretty much unreliable, unless you go really slow

hmm, Think you could try ten walls with max infills and see how strong that is?

Listen... if you're asking yourself this, it is time to make some rubber molds of your parts and pour in resin. Or cast them in metal.

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