Layers separate and become detached

[hcdbey]

The layers are separating and creating strings. It seems the ABS is not sticking to itself. Does anyone have suggestions how to fix this?

Rostock MAX V2
ABS
Hot end temperature 228
Bed temperature 115
MatterControl Version 1.3.0
Everything else pretty much at default settings except for selection of "raft".

Thanks

[jmpreuss]

My first suggestion is to bump up the temp some (235?) and see if the layers stick together. Your layer don't appear to be separating but not sticking together in the first place.

The layers are separating and creating strings. It seems the ABS is not sticking to itself. Does anyone have suggestions how to fix this?

Rostock MAX V2
ABS
Hot end temperature 228
Bed temperature 115
MatterControl Version 1.3.0
Everything else pretty much at default settings except for selection of "raft".

Thanks

[Captain Starfish]

Generally it comes down to either the filament being too thin or cold. Looking at the image, the extrusion rate seems right which leaves the temp. I never had great ABS printing under 240º and even then it depended on the day. Got myself an E3D v6 nozzle and I now print ABS at 255º-260º. The layer adhesion is superb.

[hcdbey]

Thanks for your advice. I increased the hot end temperature to 235 and continued to have the same problem. I then changed the thickness of the wall of the model from 1mm to 2mm. This time I got a full print but still having problems with the layers not sticking together. The outside of the part looks reasonably good but on the inside, it can be seen that many layers did not adhere to the layers previously laid down.

I'm new to this so I have some more questions. If I change to an E3D v6 nozzle and print ABS at 255º-260º does that mean I will also need to change the hot end or just the little nozzle?

Rostock advises not to exceed 245º or the PEEK will be destroyed so I imagine this means that the entire hot end will need to be replaced and not just the nozzle.

I live in a part of the world where it is very difficult to purchase and/or import parts such as a new nozzle so I am hoping there might be a fix for this problem that doesn't entail new equipment.

[geneb]

You may need to print that with support on the interior.

g.

[JFettig]

Agreed, it is probably too steep to be printed without support, it doesn't help that ABS shrinks quite a bit too.

[Captain Starfish]

The E3D head replaces everything from the bowden tube connector down: heatsink, fan, heat break, heater block, heater cartridge, thermocouple and nozzle. It doesn't use PEEK so can go hotter safely.

Made a huge difference to my printing but, if you can't get it in, you're going to have to play with a few things. Try get a simpler part to print, such as a 25mm calibration cube that's scaled in half. That will let you quickly iterate through settings changes and see what differences each change makes.

[Jimustanguitar]

You could also try reducing your layer height. That can sometimes make mean angles more manageable by reducing the amount that each layer overhangs.

The other suggestions are on point. Some combination of that list will get you closer to success.
More heat, slower speed, wider extrusion width, add support... PLA will print this much happier than ABS will.

[hcdbey]

Thanks for all of these suggestions. I will cogitate a bit and do some trials.

Hank

[Polygonhell]

The issue is obvious enough, the plastic is stretched as it exits the nozzle, if it doesn't have anything to hold it where it's deposited, it'll end up cutting the corner.
You'll want to make sure you are printing perimeters inside to outside, to give the plastic something to stick to.
You can increase the extrusion width, which reduces stretching, but with such narrow walls you'll end up with a single perimeter which will make the effect worse.
Slower might help, but I don't think it's an adhesion issue in the traditional sense.
You could make the wall thickness even wider, but that's probably not desireable.
As others have said support may end up being the best option. It's usually pretty easy to remove from ABS.