Printing PLA 175 C - 200 C ???

[Robert Bonenfant]

So MBI has to long of a wait for my to keep buying PLA plastic from ( 30 Day Lead Time and High Shipping cost )  - There Bots are amazing and worth the wait though. 

So ive bought from china, amazon, Matter hacks and most are saying Temp could be set at 175 - 200 C - I run mine at default but wonder if it could be better at a cooler temp. 

They all print ok but Makerbots PLA prints at like lets say a 10 and the others any in 7 - 9. Any one try dropping the temp Yet ?? Ive done it with ok results but very small onyl dropped it 10 C 

Dont want to drop it too low it hurts the machine. 

[Eighty]

I've gotten PLA from MBI, UltiMachine, and ProtoParadigm.  So far, the ProtoParadigm seems the best quality, followed by UltiMachine, and MBI comes in last.  Side note - I've been printing some parts with the MBI natural, and it's junk.  Filament varies from 1.61mm to 1.82mm.  Only jams I've gotten on my Rep2 are with the MBI natural filament.

 

Anyways, I originally used the default 230 setting.  I then tried going hotter (240).  Did that for a while, and was getting a lot of stringing during travel.  I've been printing pretty darn well with 220-225 lately.

 

I'm just guessing here, or maybe I heard it somewhere...the lower temperatures that everyone puts on their spec sheets may be for slower extrusion speeds.  The Rep2 prints a little faster than many machines, so it would seem logical that the temperature should be a bit higher.  That said, I believe Dan Newman has been printing quite successfully in the low 200s. 

 

When I get past my backlog of priority items to print, I think I'm going to do some temperature testing.  Will probably print the same item in 5-degree temperature iterations (with a mixture of long extrusions and short ones) to compare.

[Infinityplusplus]

I have been using filament from both MBI and Ultimachine. I have a spool of orange and yellow giving me some issues from MBI that I think need some different temperatures but I have not had the time to experiment. Other than that I have been running at 220-230C with all my prints and they look great! I never even opened the natural I got with my printer and with all the trouble eveyone reports from it I am going to wait till I have more time to tinker.

[Laird Popkin]

I've been finding that I have to tweak the temperature of the PLA much more than ABS, with two 'variables' - the specific filament, and the speed of printing.

In terms of the material, I have some PLA that prints great at 40 mm/s at 170, some has to be higher (180 or 190) to bond well at the same speeds. The variable isn't just the source - different colors have different additives that have different properties related to printing, even for filament from the same supplier.

In terms of speed, I have to raise the temperature when going at faster speeds. For example, if I printed at 40 mm/s at 170, I need to be around 190-200 at 120 mm/s. I'd guess that had to do with the filament spending less time in the extruder hot end, so if the extruder is 190 my guess is that the filament ends up coming out around 170.

I have to give 'props' to Jetty Sailfish, which allows you to override the temperature in the printer rather than re-slicing - that makes it much easier to tweak temperatures to do this sort of testing.

In terms of filament diameter, ever since I switched to Emmet's "minimal Mk 8" extruder, that's been a non-issue. I assume that with extreme variation would cause the extruded volume to vary, but so far I've used several suppliers and not seen this affect my prints.