Printing with PLA for Max Strength

I designed a wall bracket to store my lathe tools. Two brackets that hold pvc pipe then attached to plywood. I attached a picture of the design to illustrate. The brackets are actually reversed, the top picture is the bottom bracket and the pipe rests in the cutouts. The lower picture slides over the pipe and both are screwed to the wall in some fashions. I might add some triangular supports on the lower bracket that hold the weight of the tools to add more strength, I know that will help.

I have an Ender 3 V2 and want to use PLA. I have been using Inland PLA+ and recently bought Tough PLA (presuming it is a bit stronger). I used the PLA+ for some pegboard hooks. They generally work fine, but some of the hooks that hold screwdrivers are sagging a bit. Nothing has fractured yet.

I am looking for input on two questions:

Has anyone found a stronger or strongest PLA that is reasonably easy to get?
Are there slicer settings that would help with the strength? For example Cura has a bunch of infill options that could be used to optimize the strenghth.

I am also trying to optimize the time to print. I don’t want to run any prints overnight. I would like to keep the print time to 6 hours or less.

You can increase the perimeters to increase strength and as mentioned increase the infill also the type of infill effects it too. Think I would use gyroid for infill at 25%.

Put a chamfer at the right angles will strength to those joints. Some small triangles under the base would help too.

I think PLA Tough is just another marketing term for PLA Plus(+) which any name brand should be fine such as Hatchbox, Polymaker, Inland, eSun, Sunlu to name a few. In the USA I use a lot of Coex PLA which seems as strong with many others PLA+.

I have found that it is important for strength to look at how(direction) you print. The direction of how the filament is laid is important. Example would be print a flat plate, two or three millimeters thick. Once printed try to break said plate first of all vertically secondly horizontally and see which way the plate is more easily broken.

LegsForQuad.stl (62.4 KB)
A bit of background a quad is a quadcopter(drone).
The uploaded LegsForQuad.stl might give you an idea of what I am speaking of.
You may setup my stl, I use cura, but it will work on any other.
The leg could be setup in one of 3 directions.
The longest direction(measurement) on the leg could be in either the X or Y or Z direction.
Now look at the printer and you will see that the main movement of the head is in the x direction and that is the direction the filament will be laid down in… Therefore if the leg is laid longest in x direction it will be strongest for the loads it would be exposed to(In landing a good landing is verticle but if the wind is blowing the landing may incorporate a side ways movement). One would have to break multiple layers of filament to break the leg. In either of the other directions, Y or Z, it is the joint between the filaments that would break.

I would print the thing at an angle of around 7°. The orientation it gets mounted and is shown on the images. Just lift the right side up a little and tilt is backwards. This does require support on the lifted side, but the angle causes the layer lines to grow into the front shelf.

In this case the shown orientation would tend to separate at the screw holes, which is the major weak point. Infill isnt helping much. I would use 3 walls, so there isn’t much room to build any infill structure anyway.

BTW: How do I add files and images? I tried and I cannot select any file. The only button in the file request which is working, is the cancel one. Using Firefox.

SUNLU PLA Meta can meet your need

Seeing an image of what you are describing would be great. FWIW, the upload button works in Firefox (Mac):


Clicking opens a Window to select and upload a file.



Seeing an image of what you are describing would be great. FWIW, the upload button works in Firefox (Mac):

Yeah, it somehow works after I rebooted the server I am remotely using. Seems some update needed a restart, but no one told me. :smiley:


Back to topic: Bikehandles

This object looks like a bike and the handles are incredible flimsy. Printing standing upright, like positioned on the image below, makes the entire print flimsy. Printing on the side make the handles flimsy again.

The part on the left is the original part from the safe. It is nylon. On the right my ABS fix, where it is impossible to break the “handle” you can see broke of the original door part.

Printed “back wheel” up a little and tilted to the side. This made the part strong like hell:

As you can see on the images I printed the “bike” like a it is making a wheely while driving around a corner. The result was an incredible robust object, where it is impossible to break the handles with force.

Yes, you need more support when printed in this orientation, but it still saves plastic, as you just need to print it once and it works and is robust. The support used is tree support, so it is basically hollow on the inside, even so it looks a little bulky. Sometime you cannot create a shape for printing without support and there is no way around using support.

And as a side note: It is the door latch and not the safe door lock this part is used on. It keeps the unlocked door close until you pull the handle to open it. Just like the latch on every room door.

So stuff in the safe is as save as before, even after using 3D printing to fix it. :smiley:

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I think the PLA+ can meet your need. ABS filament or ASA filament maybe can meet your need.

I decided to redesign the project into an assembly and changed my requirements. Originally I was going to screw the brackets into a wall mounted sheet of plywood. Since I already had pegboard on most of my shop walls, I decided to make the bracket a pegboard fixture. I had to do multiple iterations of the hook spacing to get a snug fit. I also extended the supports out to take advantage of some structural geometry to add strength.

I used Inland “Tough” PLA (at least that sounds strong :grinning:) with 25% gyroid infill. I tried out Onshape for designing it instead of Freecad. Onshape turned out to be fairly easy to use and it adds contraints automatically which helps at times, but occasionally over contrains the model and I had to dig out the problem.

I attached a couple of images showing the bracket parts and final install holding my two heaviest lathe tools. The deflection of the brackets was undetectable, so this may be working ok.

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