I thought I’d share some advice I discovered for printing ABS. But first some background. I recently got a Printrbot Simple Metal with Heated Bed and in the setup process they recommend printing PLA at 210 with the bed at 70 and I thought that was a little high but it worked so I didn’t complain. When I went to print ABS I check the forum for recommended settings and got a hotend temp of 240 and bed temp of 90+. When I was printing with ABS I got significant curling that I would try to control with printing brims and using a hot glue gun on demand but I noticed that 90 degrees is right around the temp that hot glue starts to melt so I lowered my bed temp to 80 and started to notice less warp. So thought I thought hey, ABS curls because it contracts when it cools, so I lowered the temp of the hotend too and the bed a little more and it worked. So my advice to you if you’re having ABS problems is print at lower temps. Depending on your print speed you can go as low as around 210 and 60. Let me know if you have any questions.
The top layer contracts when it cools, causing the layers below it to curl or delaminate. If you print at a lower temp, there’s less cooling and therefore less curling.
@Adam_Steinmark Individual material types print at differing temperatures. A good quality 4043D PLA will print at 160C upwards (I use 185C).
Likewise I have found some Abs will print at lower temperatures. The 3dfilaprint ABS I use happily prints at 220C.
For bed temperatures I use 125C for ABS and 70C for PLA. These equate to 110C and 55C respectively at the glass surface.
I prefer to use lower temperatures where possible after determining that the material performs adequately after printing.
The only issue which might appear with lower printing temperatures and ABS is that the layers split more easily.
The degree of curling is likely a function of the difference between print temperature and ambient temperature. The lower the ambient temperature is, the more curling of the edges.
Also you have also just seen for yourself the same effect with lower print temperature.
Moving air also robs heat from the print, so reducing drafts is a good idea for reducing curling.
Ambient temperature and drafts are best controlled by enclosing the printer. Not so easy with the Printrbot simple metal!
@Thomas_Sanladerer What hotend temp do you recommend for my printer?
@Paul_Gross I was thinking about making a box made of acrylic panels with 3d printed brackets and hinges on the front and top for easy access. Big box though.
@Adam_Steinmark whichever one works for you.
There are ABS filaments which print great at 220C, others need 275C (wouldn’t recommend that on the Simple Metal) to print well. Also, the thermistors in out hotends can have rather large tolerances, so the same temperature that displays as 240C might be 260C for someone else.
Do a handful of test prints (benchy) at different temperatures and use the settings from the one you like the most.
@Thomas_Sanladerer Thank you
@Adam_Steinmark I also own a Printrbot simple metal.
Making a box of acrylic panels seems like a
good idea to me.
But there is a trade-off when you enclose the printer - for long prints (several hours) the extruder can get too hot, so the heat creeps up the filament in the tube, past the entry to the tube and melts the filament before the tube into a lump that can no longer be pushed down into the extruder.
There are ways of dealing with this too - extra heat extraction on the extruder like this:
http://www.printrbottalk.com/forum/download/file.php?id=6704&mode=view
@Paul_Gross Thanks for the help. I’ll make sure to incorporate the fan on the extruder when I make the box. I’ll start on that project once I finish my filament storage system and make something to organize all my tools. I’ll post some pics on this community once it’s done and probably the printrbot forums as well.
The simple metal will go to 275c if you need it. I’ve considered a smaller box on top of the print bed with complicated bellows to contain the heat and keep it as small as possible… Definitely out there. Good luck!
Wow I reached @Brook_Drumm himself! Thanks everyone for the help, I really appreciate this community.
Thanks @Adam_Steinmark , I look forward to seeing the photos of your enclosed Printrbot.
@Mark_Rehorst I chose acrylic because I still wanted to be able to completely see my printer. Also I’d have to remove the motherboard from the printer with your setup. Interesting concept though.
@Mark_Rehorst The light bulb might be a good idea and yeah I’ll probably keep the ATX power supply out of the box.
@Mark_Rehorst
Another simple, quick and cheap, but effective way to increase the enclosure temperature is to stick aluminium foil sheets to the insides of those acrylic panels. Especially under the top panel, where most of the heat is lost.
It’s also easy to add convenient viewing windows by judiciously cutting away some foil from the front or sides.