Page 1 of 1

ABS to PLA - Procedure

PostPosted: Fri Oct 18, 2013 12:26 pm
by flickerfly
Is there any special considerations I should take when changing from ABS to PLA (or back again)? I seem to recall hearing a whisper about something somewhere, but I'm not sure where.

Re: ABS to PLA - Procedure

PostPosted: Fri Oct 18, 2013 3:15 pm
by orcinus
Keep the temperature at about 230-240, or whatever gets your ABS going.
Feed PLA into the extruder (preferably of different color than the ABS).
Purge until all ABS is out, then purge some more in case there are flakes left.

Reduce the temperature to PLA temps (185-210, depending on PLA).
Purge a bit more just to be sure.

That's it.

Re: ABS to PLA - Procedure

PostPosted: Fri Oct 18, 2013 3:25 pm
by flickerfly
Thanks, the idea of the procedure is to make sure no unmelted ABS clogs the nozzle after switching to PLA?

Re: ABS to PLA - Procedure

PostPosted: Fri Oct 18, 2013 5:06 pm
by TLHarrell
Correct. Since ABS melts at a higher temperature than PLA, if there were any bits of ABS left over in the system and they moved into the nozzle, they would not melt... therefore would cause a blockage.

Re: ABS to PLA - Procedure

PostPosted: Fri Oct 18, 2013 5:11 pm
by flickerfly
So going PLA to ABS shouldn't require even that (though it is probably wise) and if I do develop a clog, should be able to resolve by simply heating up to ABS temps?

Re: ABS to PLA - Procedure

PostPosted: Sat Oct 19, 2013 1:47 am
by orcinus
Yup. Although it's still a good idea to do a thorough purge, because PLA heated to temps higher than, say, 230, can start outgassing, causing pops and whatnot (no fear of blockage, but it can cause irregularities in the extrusion).

Re: ABS to PLA - Procedure

PostPosted: Fri Oct 25, 2013 1:50 am
by funkybuddha
I follow this process religiously and have never had any problems switching between ABS and PLA - and I switch quite often.

Re: ABS to PLA - Procedure

PostPosted: Fri Oct 25, 2013 3:23 am
by flickerfly
Thank you funkybuddha.