I have been attempting to print models in ColorFabb’s Bronzefill, which is a PLA-based filament that is loaded with real bronze powder to add weight and metallic qualities to printed models. Due to its material properties, it is recommended that Bronzefill be printed at significantly slower speeds than typical PLA. However, temperature settings remain in the range of normal for PLA.
I am attempting to print on a Bambu A1 Mini which is generally a reliable machine. I have attempted prints on both the textured PEI plate (alcohol washed, dish soap washed, you name it) and a new smooth PEI plate.
No matter my settings and plate, my first layers almost never stick. In particular, the first extrusion that the printer lays down (after laying the prime line) never sticks to the build plate. It almost bounces off of the plate. This is especially strange, because sometimes, if I get the small deflected filament off the nozzle and bed in time, sometimes later extrusions in the first layer will begin to stick to the plate.
TLDR: I am trying and failing to get Bronzefill to stick to my build plate despite proper temps, slower print speeds, and very clean PEI build plates. If you have experience printing Bronzefill, particularly on an A1 mini, have you had such troubles and what did you do to solve them?
Thank you in advance for the help.
P.S. It’s worth noting that I have successfully printed Bronzefill on a Prusa MK3s machine with the older steel plate. Therefore I am especially surprised my A1 Mini is struggling so much.
Thanks for your varied tips. I am especially interested in your last two suggestions. Minimization of jerk is a clever idea. I’ll see about that. Line width also a reasonable point.
And yes, I have started using a .6 nozzle and am noticing better adhesion overall.
Since I posted this I’ve been digging in again and would like to offer a piece of info for anyone else struggling with this: ColorFabb suggests that flow rate should be increased slightly… in some premade settings they’ve published for the P1S they set it to 1.05. However, I find that increasing flow rate severely increases failure rate. Not sure why.
I think the best course of action depends very much on the failure types you are seeing. If, for example, you see a the bottom surface lines being pulled back from the inner wall, you could either reduce accelerations (which would slow down the entire print unless you use a 1st layer modifier) or the circumferential pattern which cuts down on u-turns and can help a lot.
As for the wider lines and the increased flow, they both follow the time honored tradition of “if you’re not willing my force I’ll employ”
Of course, both have their own risks.
A slight 1st layer overextrusion is usually part of the presets anyway (PLA flow usually 0.98, preset 1.00). But it can become a problem if subsequent layers are not able to compensate (for example printing thin solid layers fast) or when using highly adhesive materials like PETG. And the higher the deliberate overextrusion, the more challenging the print.
Wider lines also increase the force with which the material is deposited on the build plate while avoiding overextrusion. However, they do tend to have a more rounded exterior (i.e. more porosity in the final print) and are more prone to edge exfoliation.
Since ColorFabb recommends a flow rate increase, I’d start with that and see what the failure (if any) looks like.
Thank you for your further useful insights. Clearly this isn’t your first 3D printing rodeo.
I am quite surprised to find that, following the advice of another printing friend, I tried using the Generic PLA setting built into the slicer, and only made my custom adjustments in print settings. So, default flow rate, temps, etc. for “generic” material.
Shockingly (to me anyway, I’m now seeing successful first layer adhesion. Still some wonkiness with small initial walls—which some of your tips definitely will assist with. But it’s beginning to look like something in my custom filament profile was causing the issue.
I’m having trouble understanding why ColorFabb recommends an increased flow rate. If I use the generic PLA setting in slicer, and only increase the flow rate to ColorFabb’s recommendations, and of course keeping slower print settings in place, I actually increase my failure rate. Isn’t that odd?
Thank you again for your insights. Happy printing.
Glad to read that you have overcome those pesky 1st layer issues.
Thinking a bit more about the overextrusion recommendation, it does actually make some sense. If the particles used in the filament do not adhere to the print plate themselfes they’ll reduce the contact area, making 1st layer adhesion more challenging. In the past, a common solution was to just “press” the extrusion further into the build plate as the slower speeds of older printers were more forgiving to overextrusion on the top of the layer.
There’s a further, much more elegant solution to improve adhesion though: increase bed temp by 5° and nozzle temp by 10° for the first layer.
I expect a high percentage of (large, non-functionalized) particles to also bear some responsibility for weaknesses in subsequent layers. A higher nozzle temp may help a little, but bridging and overhangs will quickly become much more difficult.
, and happy printing and experimentation with the bronzefill. It would be very interesting to read about your experiences in the future
I once used isopropyl alcohol to clean one side of my textured PEI plate. Now, the first layer never sticks to the plate. I currently use the side of the plate that I didn’t clean with alcohol, and it works fine. I suggest you don’t clean the build plate with alcohol. I think it damages the plate sometimes.
Isoprop tends to wash the gunk into the valleys of the textured plate. You can try to get it out again with dishwashing liquid, warm water, a stiff, clean brush and a lot (!) of muscle grease. May need to repeat several times.
In extreme cases, you can even try to “re-life” the plate side with steel wool.
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