Stronger FDM 3D prints, using "brick layering"

[subscriber]

Good point, Scott.

Humans like simple ranking, with clear a clear "best" designation.  Meanwhile "best" depends on a lot of other factors that may not have been mentioned or considered.   So, as always, context matters a great deal.

[TorqueMaster]

I often use relatively thin walls and 100% infill. With crosshatched alternating layers. (XY rectilinear pattern). So I’m thinking the brick patterns are not applicable in those cases.

Yes -- very good point  -- the fill you mention is going to be hard to beat for a solid part.  Sometimes I even set it up to crosshatch every 45 degrees, 4 layers before the pattern repeats.

The brick wall I suggested was more for the outer walls of the object -- in particular for LDCs, to get a bit more cohesive outer shell where there is no infill. 

[rsterne]

One thing I have found with Cura is that if you specify 100% infill, the infill will not overlap with the walls.... If you use 94% or less, then it will.... I find that printing infill at 100% with the normal 100% flow leaves a rough surface, not so bad if you use 94% infill.... If you don't have that rough surface (which I think is overextrusion), you could always use 94% infill and crank the flow up to 105-107%, get a completely filled part, and still get it bonding to the walls with the (typically 30%) overlap....

Which infill do you prefer for solid parts, lines or zig-zag?.... I sometimes turn the infill direction on the top and bottom so that the outer layer is parallel to the long direction on the part to reduce flex in that direction.... Alternately, I use all walls and no infill, which is probably better if the surface is in tension.... For vertical compression around screw holes and the like, I don't think it matters, but more walls running around the hole sure can't hurt, especially it you are threading it....

For something like a moderator, where you want hoop strength, I would use all walls, because the filament is stronger along the threads.... It might even help to use a random Z seam position, so the hops between layers don't all line up like a zipper....

Bob

[Scotchmo]

Prusaslicer lets you control the overlap of infill to walls. Though that’s never been a problem. I always use 100% flow. But I measure the average filament diameter of a roll and set my slicer to that value. It’s usually between 1.71mm and 1.75mm.

[TorqueMaster]

That's an interesting observation on the infill not overlapping the walls.  I'm pretty sure there is a setting for how far that overlap should be (mm?) and it should not vary based on infill %.  Back when I was using Cura 4.something, I remember bumping that value up slightly because I did not like the almost nonexistent overlap I was seeing.    Cura is a constant work in progress, sometimes feature changes domino into unconsidered effects somewhere else -- you may have found one of those.  Fortunately, it is configurable enough that you found a "workaround."

For solid infill I usually use lines.  With monotonic order if I remember to set it.  I do not use zigzag much -- most likely on a much less than 100% infill project.

Yes, I typically do ~3mm walls on moderators -- all walls for the shell but some endcap and other really thick areas may get some criss-cross action in the middle. 

My Z seams are good, but not invisible, so I keep them linear for esthetics.  I dislike the surface "zits" caused by random.   Actually, we're experimenting with fine surface textures that improve the overall look, and effectively hide the seam, so I probably COULD switch to random and no one would notice the zits that that causes.  Hmmmm.... thanks!

[subscriber]

TM, please post the latest textured mod image, that you printed for Steve.

[TorqueMaster]

Very large 3D printed moderator with "basket weave" surface texture added. 

[subscriber]

Thanks, TM

I hope the other folks notice how smooth and even the untextured surfaces of that mod are.

[TorqueMaster]

One thing I have found with Cura is that if you specify 100% infill, the infill will not overlap with the walls.... If you use 94% or less, then it will....

Bob,
I was thinking about this a bit more -- I have not noticed it to any great degree, so have not looked for a solution. 
But I realized I use the "Alternate extra wall" feature most of the time -- it overlaps the wall-infill junction every other layer -- and the infill will overlap the junction on the other half of the layers.  This alternation creates a much stronger junction throughout the part, rather than the same, possibly weaker, uniform vertical junction. 

[rsterne]

You are correct, of course, the alternate extra wall is the best....

Bob