I sure hope my settings work based on my tests

Ok, so the only settings i can find online to follow for printing is the infill percentage and 2 or more walls.

According to my tensile tests and CNC kitchens tests, 2 walls at 50% infill, which is 5% higher than all infil recommended, has a specific strength. Now, if i do 4 walls and 25% infill, i get almost double the strength and it prints faster.

What have you guys been using as settings? Specifically for the wall count and infill. that is all i am curious about.

thanks

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That’s a dubious claim.

I wouldn’t go below Ryan’s recommended infill settings.
I seem to have good results with 4 walls and the recommended infill for each part.
Lots of folks have likewise had good results.

Most of the posts I’ve seen from folks who tried to go lower were to report that it didn’t work out too well for them.

You’re going to print a parts set and then use the machine for a long time.
Why skimp on a few hours of print time?

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it is not a dubious claim : ) and it should be 25% infill, not 20%. ill be sure to edit that.

2 walls and 50% infill i get a failure break at 5kg. With 4 walls and 15% i get 8kg, 4 walls and 25%, its close to 10kg. Mind you, all tests were in TENSION. Infill is NOT what gives parts its strength… well, thats not true, it helps with compression and impact forces. The most strength comes from the walls.

Since you have had good luck with 4 walls and the recommended infill, then i shall do the same.

FWIW I think that comparative tests on simple strips of materials are useful but they have shortcomings if the results of those tests are applied carte blanche to more complex structures.

I printed mine with 5 layers and the recommended infill percentage, using gyroid infill. This is way out of line with the community generally, and there’s an ocean of evidence to show that it’s simply not necessary, but I am just comfortable with the margin for error printing that way.

I also do not consider time to be an element in this equation, as in the context of the time of the project and the expected life of the tool it is irrelevant. Of course when it takes a couple of years to finish anything a week or two extra printing is not even noticeable!

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i have not used gyroid infill yet. Is it decent?

i use rectilinear or triangles the most. But if a part is going to be in compression, i go with honeycomb.

Yeah time is irelevant like you say. I do know i mentioned it, but i wont even get my control board until Wednesday and i wont get pipe until next week or so. i have time, and while its printing, its not like im just going to be bored and have nothing else to do haha

It’s my standby when the load is from multiple directions. Not tested (nothing has broken either) but it makes sense to me to use a non directional infill for non-linear loads.

I guess you could take that argument on the LR3 for instance and fairly say that the infill in the plates and braces are there simply to keep the load bearing skins apart - but I don’t care! :rofl: :rofl:

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your idea makes sense. that is why i make sure not to choose any type of infill that is labeled aligned because it can break alot easier with non linear loading. That was part of my reasoning for asking the original question about infill because i know the loading is non linear and not always in tension either.

Honeycomab is great too but takes even longer than gyroid, at least in Prusa Slicer. Wish i had testing equipment at home like i do at my lab at my university.

I wish you did too - I could keep you up all night for months on end! :grinning:

Don’t overthink it for this project though, the knowledge is useful but as I’ve said V1 projects are well and truly tried and tested - build in a way that makes YOU happy.

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yup, i would be up all night just testing my own stuff too. I may have to start looking into my own lab at home.

I like to test things and i really want to see how well a part at 4 walls and 25% infill compares to 3 walls and 45% infill or even 4 walls and 40% infill. I love doing stuff like that but i need the equipment to do so. I mean, i guess i could print some cubes and go to the local gym and just add weights until they crush haha.

There are so many variables. My five walls were at 0.4mm with 0.2mm layer height - many here print 0.6 or even 0.8mm so when you say “4 walls” I think we really should be talking about “wall thickness”

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Yes, this.

Frankly there is so much more to this than a simple set of parameters. Having a well tuned printer and slicer setup that achieves good layer bonding is much more important overall.

Yes, I see you have the fundamentals down. You’re capable of finding optimizations.

As you note, the parts see more than just tension.
They see compression and impacts, also plenty of vibration.
Plastic can also suffer cold flow and other plastic deformations. Hence its name.

Part of the fun of building your own machine is the learning and discovery of it.

Many of us would be really interested to see comprehensive test results.

I’d be particularly interested to see benchmarks like parts longevity comparisons, or machine dynamic response comparisons. Those will have as much to do with your abilities and techniques as an assembler as they will with your parts strength.

One interesting observation about Ryan’s designs are that they are “more than good enough” in a way that the machine and its parts are fully workable in a very affordable way.

I look forward to seeing more of your progress and any test data you want to share.

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My wall thickness is always 0.5mm extrusion width for functional parts and for detail prints, like sculptures, i use 0.25 or 0.3. all on my 0.4 nozzle.

Compression and charpie tests is what i want to do. Tensile tests have been done over and over.

A solid piece of mold injected plastic will have really good compression, so naturally as you lose the solidarity of theninside, it will fail faster, but what about the dynamics of how a certain type of infil reacts to compression. Ie, what if a 50% infil of triangles is actually stronger than 80% infill of triangles because of how the infill behaves under compression? Does that make sense?

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True, so for me, 4 walls at 0.5mm thick so a total of 2mm

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