This is my first post here as my K8400 hasn’t been fully assembled for a long time. Right now I’m trying to get my settings right to get good printing results.
The first actually useful part I want to print is a housing for the mains plug and switch. Even though many others have done the same mod I designed my own case because I didn’t want to use those all-in-one socket/switch assemblies simply because I didn’t have one around while I usually always have some standard-spec switches and sockets.
I made this part with 100% infill because I want it to be as sturdy as possible. Now there is a severe printing problem obviously, the layer which is the top layer in some areas of the part but not the overall top layer (visible in the middle) is super ultra rough and obviously kept those layers from sticking correctly that build upon it. Please see the pictures, sorry I couldn’t get 2nd and 3rd focused.
Which setting do I need to tweak in what fashion to get this right? You can see that the top surface of the rim of the right-hand part is very smooth and much better and I wonder why not all top surfaces seem to be done the same way?
Hi,
To get nice prints there are a few parameters to adjust :
Temperature : PLA 190° - ABS 220°.
Flow : 75%
Retraction : 3-4mm and 140mm/s
Infill : don’t set it above 60% and use the linear infill.
is it ABS or PLA your printing with? Based on the photo it looks like ABS but i could be wrong Additionally what is your Temp on the nozzle and what is the retraction distance and speed and your multiplier setting. Another thing to look up is the print speed.
Also look up if you can the filaments Melt flow index and the Density in (g/cm3)
For the most on a default printer setup with ABS without mods to the firmware. 230C and 1.0 on the multiplier and 3,5mm retraction and around 125-150 on the retraction speed usually works ok. But if the melt index is higher or lower that can change along with the density of the filament. For PLA usually around 210C and 0.9 on the multiplier. The flow can be tinkered with 75% is usualy used on the default setup. If you correct some stuff in the firmware as some of us have done the printer behaves alot better.
In your case it is under extruding filament. The reason for why it does this can be many. My gutt feeling tells me the retraction is to long making a blob in the ptfe tube and making the stepper motor for filament feeding jumping. Have you ever heard the stepper motor for the feeder tap over and over? It is a unmistaking sound.
But as i wrote there can be many reasons why this happens. Simplify3D have a very useful guide for varius types of printing quality issues that i tend to come back to over and over to myself at times. https://www.simplify3d.com/support/print-quality-troubleshooting
On a side note. You dont need 100% infil to be honest on that part lower it down to around 30-50% linear infil usualy works. Myself i have started using a fast honeycomb pattern that i find best for most things i print these days.
Sorry I forgot to mention that this is a PLA print using Filafarm filament. They recommend 205° but I don’t have the MFI or density. I will however ask the manufacturer and try to get that info.
Right now the temperature is 205°, retraction speed is 110 and retraction distance is 4. Flow is 100%.
By the way I’m printing rather slowly, IIRC the settings are
(My software is German therefore I don’t know the exact English denominations).
Maybe I should use lower infill but at least in the end I’d like to be able to print 100% just for the reason that for me the parts somehow just don’t feel right if they’re light and (partly) hollow.
I think I haven’t heard the sound you describe Marlark.
Would the following corrections be reasonable for a second try:
decrease temp to 195
increase retraction speed to 150
decrease retraction distance to 3
Should I increase the flow also? This is what Simplify3D suggest in case of under-extrusion or would this rather be a band aid solution if the flow is already 100%?
Well the problem as i see it is that most of the print is fairly ok in term of how it is printed. But what you might want todo is print a cube lets say 2x2cm or something and switch to 3,5mm retraction and 150 on the retraction speed. It is good that you aint printing fast because in this case slow is good because it removes a error variable.
This is the settings i use for PLA 0,21mm layer prints for the most.
But my firmware is modified. But considering on how some of your print is looking you might wanna go for 75% based on the reason your using the original firmware version.
After I tweaked the settings according to your recommendations the result is much better, see the pics below. Beforehand I need to mention that this time however I had a huge lifting problem. Last time I used blue tape but in some locations it had lifted off the buildtak together with the PLA so I tried without tape this time but it didn’t stick any better. I include a closeup of the underside of the print, maybe you can tell me if this is looking good or whether the bad sticking could come from a not optimal first layer. I can say that the very first layers seemed to stick well initially but later they must have lifted off. Therefore I didn’t finish the print.
The top surface has improved very much and because this surface is inside it would be acceptable in this case. Was it the outside of another object it would however still be pretty rough. In which direction should I do some further tweaking?
That warped a considerable amount there I hope you didnt use blue painters tape on the buildtak sheet. Because that actually wear out the buildtak’s properties. Anyway there is a couple of things that you can do to increase addheasion to the buildtak. Sins this is a big item this gets more into a problem then on a smaller item.
Tip 1 : Slow down the first layer print speed 50% is a good start
Tip 2 : Make the first layer thicker/width around 200%
Tip 3 : Turn off the fan the first couple of layers and then turn it on after a layer or two later.
Tip 4 : Print the first layer with a lower temp then the rest of them
The consept of warping is that the filament gets cold to fast making the filament lift in the corners that is why you slow down printing and put messures in that makes it cool slower on the first layers.
You also have the option of using a raft. But i dont realy like the raft consept myself.
Side note Tip : Get a heatbed and use DimaFix on it. <<< ultimate solution for batteling warping. You can kiss warping goodbye that way.
Anyway a couple of ideas for you there. The top layer looks better it aint 100% but atleast your on your way in the right direction
Actually I was using the blue tape on the buildtak, never before have I heard that this wasn’t a good idea… Would glue residue be left behind or what’s the deal there?
Thanks for the other tips, I’ll be trying them out asap.
And I’ll certainly get a heatbed sooner or later anyway to be able to print ABS as well but until that has materialized I’d still like to achieve acceptable results.
I was able to get an acceptable print by following tips 1 and 2. I wasn’t able to follow tip 3 because I couldn’t edit single layers. Tip 4 I tried but with a bad result. BTW. this time I put the blue tape on the other side of the glass… Now the edges still lifted a little but the part is usable for what it is even though not perfect.
Afterwards I printed some smaller objects directly onto the buildtak again and this time they were sticking to it like hell, I even damaged the buildtak in one spot in the process of removing one object Seems that the changed settings have made a difference.
Additionally what is your Temp on the nozzle and what is the retraction distance and speed and your multiplier setting. Another thing to look up is the print speed.
I hope you didnt use blue painters tape on the buildtak sheet. Because that actually wear out the buildtak’s properties. Anyway there is a couple of things that you can do to increase addheasion to the buildtak. Sins this is a big item this gets more into a problem then on a smaller item.