printing gridfinity
Hi,
Is here someone who prints Gridfinity stuff on MK4/S and would be willing to share experience and settings for these? I figured it might be frequent enough project, though relatively tricky, so not everyone has to reinvent the wheel 😁
Anyway, issues I have encountered so far:
1. Base grid 5x5: that's almost across whole build plate, I got that weird layer shift by half grid unit, I saw it reported in different thread. 5x3 worked just fine. Might be good test case for traking the layer shift problem down. Printed in PETG, 0.6 nozzle, satin sheet.
2. Boxes. Here I have problems with warping. Here primarily I'm curious about other settings. The long straight extrusions are known problem, but where else should the printer's speed shine? Anticipating it, I went light with 1x1, 2x1 and 3x1 boxes of 3u height. And the warping was present already with 2x1 and quite significant with 3x1. I hoped, that splitting of the few bottom layers into the squares would reduce the stresses causing the warp, but clearly not.
I have printed boxes in PLA, 0.4HF nozzle, cubic infill, basically default settings, smooth PEI, cleaned with IPA.
I cannot wait for forums wisdom 😀
RE:
I just finished printing a bunch of trays using my own openscad model: https://www.printables.com/model/1254939-trayfinity
Disclaimer: I have a MK3.5, not a MK4, so not all I say may apply.
Indeed, printing without warping is a challenge, I've not really succeeded in completely eliminating it, instead reducing it to a level that it doesn't bother me anymore.
One of the features that my openscad model offers is a thick brim. Standard slicer generated brims are only a layer thick, which will not be really resistant to peeling forces. You can make your brims wider, but the model deformation will simply peel the brim off the bed. Thicker brims offer better resistance.
Maybe the gridfinity stuff you are trying to print is simple enough to generate with my model. If not, you could use it to only generate a brim to combine with your gridfinity objects. Since gridfinity is a standard, that should work. You will have to play with offsets. Two PrusaSlicer settings of interest are 'Elephant foot compensation' and 'Slicing gap closing radius'. You need the first one to make sure the separation between brim and object isn't too large or too small. When you open my model in the openscad customiser, look under 'output options' for the brim settings. You can specify a separation gap to tweak the distance between brim and your object. You can even use a negative value if necessary. Under the output options you can also select to only generate a brim.
Since the larger trays extend to the edges, they end up in the area where the bed temperature is maybe not quite 60 degrees anymore. I printed the larger trays with a bed temperature of 64 degrees.
As always, cleaning the print surface is key. I take no chances and for the larger trays I first clean it with hot water and dishwasher soap, dry with a paper towel and then clean it again with IPA.
To increase adhesion, it can help to lower the Live adjust Z a bit so the first layer is really squished into the print surface with some force.
Secret tip: you can print gridfinity objects up to 6x5 by specifying a custom bed shape. The 2 extra mm needed are there, but only just. You may need to shift your print sheet left or right by a fraction of a mm.
