ABS - Printing problems
I have a problem with ABS prints. Small one are OK, but now I have to print really big ones and I have a problem.
I am using Prusa MK3S+, it is in box (DIY Ikea table mod), and using PRINT-ME smooth ABS (red). Used brand new spool of ABS, just unpacked from vacuum bag.
I also tried Prusament ABS, got a bit better result but still not good.
Here are the pics.
As you can see i have delamination between layers at certain point (always at the same spot, tried 4 times), only on the outer edges, not on the inner ones. Adhesion to the heated bed is good when using glue stick. Also, I have to use binding clips to hold the sheet attached to the bed because print is lifting it up (print is stuck to the sheet so good).
So, adhesion to the bed is excellent, but between layers is not that great at some point.
I am not an expert in 3D printing so I need your help. This looks to me like there was no enough heat, so layers didn't bond.
3mf file is here: Model
Please tell me what do you thing about this, what could be the problem, and how to solve it.
TIA,
Milentije
Reasons why that happens are pretty much known...
...This looks to me like there was no enough heat, so layers didn't bond....
No, there was enough heat and layers did bond as they should. The problem happens as layers start to cool down during print.
In most cases, most part of the print (thick base) is closest to the bed. And because bed temperature is very high (above 90°C) this base will hold high temperature till the end of printing -especially if it has a shape of a closed block. Now above that bottom part, you have vertical walls, which cools down much faster than base. And you guess it: when cooling down, material starts to shrink. The problem is, bottom part cools down much slower than walls above it and so bottom part shrinks slower than walls. That shrink force is strong enough for layers to start separating.
I hope all above makes some sense to you. I have no solution for how to prevent that (maybe additional heating inside enclosure), because it also depends on part design/size you wish to print. Maybe other will come will some good ideas.
[Mini+] [MK3S+BEAR]
More questions
Hi Bogdan! Thank you for your post.
Yes, it makes sense.
With a current configuration, I am getting 45-50°C in the box while printing. What temperature shout I reach to be able to print this? Will thicker walls help?
First I need to say is, I don't see myself as experienced with ABS.
Temperature up to 50°C inside enclosure should be enough, I think -but then I have no idea what additional 5°C would do. If I would go that route, then I would try to better thermally isolate enclosure (is simpler than making thicker walls).
Maybe you could try opposite and choose lower bed temperature. If you're now at 100°C, try with 90°C instead (as long print sticks to bed). That would allow base part to cool down just a bit faster... keep in mind: the goal is, whole printed part should cool down evenly inside enclosure.
And again, I really hope my way of thinking is reasonable 😉
[Mini+] [MK3S+BEAR]
RE: -
Maybe combo will help. Better isolation with 10°C lower bed temp. Have to try that, but it will take some time, printer is busy now.
If anybody else has any idea, please write it. I am just a noob looking for solution. 🙂
ABS - Printing problems
@milentije
You might try venting your enclosure, in my experience 37-40C at the highest in the enclosure for ABS. 37 seems to be optimal if you can maintain that through out the box. I looked at your .3mf and the settings seem mostly reasonable.its a cooling issue for sure.
I'm not sure why generate supports is turned on and elephants foot should be set to zero with a brim in my experience, but none of those should be causing your separation issues, I think your keeping the enclosure to hot and you should try to do a controlled cool down of the part at the end of the print. also, unless you think this model is going to take a beating, 2 perimeters should be ok.
Based on the info I found on the PRINT ME smooth ABS website I wouldn't be afraid to try printing this filament at 260- 265C with the enclosure temp maintained at 37-40C
Good Luck
Swiss_Cheese
The Filament Whisperer
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Swiss_Cheese thank you for your post.
Supports are left from previous model.
Elephant foot compensation is something new for me, I found it last night. Didn't know it was there. But anyway, I do not have problems with that option.
I need 4 perimeters because I need to make threads in holes, and part will be abused by the nature of its "job". 🙂
So, one of the settings I have to try is nozzle at 265°C and enclosure at around 40°C.
Will try, thank you.
temp
Swiss_Cheese thank you for your post.
Supports are left from previous model.
Elephant foot compensation is something new for me, I found it last night. Didn't know it was there. But anyway, I do not have problems with that option.
I need 4 perimeters because I need to make threads in holes, and part will be abused by the nature of its "job". 🙂
So, one of the settings I have to try is nozzle at 265°C and enclosure at around 40°C.
Will try, thank you.
That should work. I am very experienced with ABS and this delamination is not typical. I agree with above that is has to be temperature related.
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Chuck H
3D Printer Review Blog