Aargh, struggling with ABS warping/cracks!
Over the last few days I built an enclosure (60x60x60cm) and then added a separate PSU for the heat bed.
By using a solid state relay I now run the heat bed at 30V, which really speeds up the heating time and in turn means I can now easily reach 120C.
However, none of the above helped much!
I’ve turned of all part cooling/fans, except for the fan on the E3D V6.
I am running the hotend fairly cool at 215, would it help to increase it?
The hypothesis being that it would give better layer bonding…
Layer adhesion is pretty much the prime reason why you’d want to increase your print temperature, other than getting the plastic to flow more easily. 215C is very cold for ABS, normal temperatures are 230 to 240C, so try somewhere in that ballpark. I run all my ABS at 250C, because… i can. Just keep in mind that when increasing temperatures, you might run into “curling” issues on the underside of overhangs.
Yeah I do know that 215 is quite cold. This is MG94 ABS which seems to handle it fairly well though, and gives excellent results otherwise.
Do you have problems with bridging when running it that hot?
ABS is much more tolerant there than PLA, which will just drool out of the nozzle like water when you’re printing it too hot. So… no, I’m not seeing any problems there. Bridges work just fine for me, but then again, i have no idea about what the cheap CTC brand ABS I’m using is made from (might be 80% recyclate for what i know). I have printed with some virgin Polylac 747S that i extrudes myself, and that did give very nice results at more humane temperatures.
I’ve always found MG94 to like hotter temps but that could be the manufacturer. Its based off stratasys M30 which they run at like 315C if that tells you anything.
I run at 245 to mitigate the same issues your having. My layers fuse quite well and as long as I don’t have any huge bridges it isn’t an issue.
I found that a lot of inter-layer separation and warp can be mitigated by design. Reduce long straightaways by adding holes in the part to break up flat walls. Fillet all the corners. I find the second one gives a better finish overall as the printer can arc around corners rather than trying to do a sharp 90. I’ve only printed ABS for the past 3 years, and this is what works for me.
I also had to put my E3d V5 to 245C to get MG94 from coex to print well. I run PE747 ABS at 235 generally. So I second the ‘make it hotter’ suggestion.
Also maybe try a different slicer.
Ok, an update:
I redid 1/2 pieces of the plate that kept failing, this time at 245C.
The piece came out very well with none of the cracks/separation I had earlier!
The fact that I only did one of the pieces may have helped a bit, but the bump from 215C to 245C was IMO almost certainly the biggest factor.
Thanks guys:)
Just to add some data in here, I also find MG94 wants to run a little hotter than the more common PA747 ABS. I do MG94 at 245 whereas PA747 runs nicely at 235. The MG95 will delaminate a fair bit otherwise.
This is one of the many reasons why manufacturers telling you what resin they’re giving you is important.
Indeed, I bought this roll precisely because it was advertised as MG94.