Strengthening your FDM 3D Prints
Layer shells over infill
Careful selection of materials
Layer Shells Over Infill
When it comes to strengthening parts, most people's instinct is to run up the infill percentage. However, you'd be surprised to know that the thickness of the walls of your prints matters way more. The higher the percentage of infill you use, the less return in the strength you'll gain. Not to say that you should ignore infill, but anything in a 20-40% range will do the trick. But make sure your walls or "shells" are at least 2mm thick, if not more.
Material SelectionMake sure to select the proper filament for your application. Most people may pick PETG or ABS and completely rule out PLA. You'd be surprised at the number of applications we've used PLA in. PLA is stiff, and with the proper additives, can be very strong. Our matte PLA is perfect for this. The additives that give it its beautiful finish also make it more impact-resistant. We've sprung for PLA on this magnetic iPad mount that's been in service for over a year without ever breaking.
We also use these 3D printed bins to help us better rack our flexplates. These bins are a very recent addition to our warehouse, so we're testing with PLA & PETG to determine what material stands the test of time. Each container can store up to 35 flex plates, totaling over 80lbs. Keeping that much weight upright requires some seriously rigid and stiff parts.
Slicer SettingsSlicer settings also make a massive difference on the end strength of your part. Here's a list of general rules for slicers.
- Run hotter hot end temperatures. The hotter the plastic, the better your layers are going to bond to each other
- Orient your part so that the layer lines are running perpendicular to the direction of load or stress. The bond between layers will always be your weak point in a print, so you don't want to push or pull against them.
- Use a smaller layer height. The smaller the layer height, the stronger the print.
- Use rectilinear infill.
- Turn your part cooling fan down as low as possible. It might make your prints a little uglier but will promote layer adhesion.
- Turn up your extrusion width to 125%