Annealing PLA

Mostly Printed CNC - MPCNC Troubleshooting
#1

As I watch all the printed parts slowly emerge from the printer I began wondering how well this machine will hold up to the summer heat in my unconditioned workshop. I’ve seen a few articles on annealing PLA in an oven or hot water bath (Sous-vide?). While it does seem to improve strength and heat tolerance there is unpredictable “shrinkage”. I wonder if it is even worth exploring and experimenting. One article --that I can’t seem to find now-- even compared the Proto-pasta PLA specifically designed for annealing “HTPLA” to plain PLA and found limited improvement with the much more expensive Proto-pasta stuff.

Has anyone annealed your PLA? Or how experience any issues with summer heat?

#2

Tom on youtube has a very detailed video on this.

The parts shrink and most gain no strength.

#3

Mine lives in a barn. I had some parts crack, but have replaced most of them with petg. No issues since.

#4

I have had 2 versions of this machine… PLA and PETG. PETG is the way to go. I printed all parts 4 perimeters 50% infil with a 0.5mm nozzle. Rock solid no heat concerns.

#5

Well darn. I guess I should have thought about this issue before I printed most of the parts. I’ve messed with PETG some, I only have one roll of it, and I don’t have it dialed in nearly as well as PLA. I might just see how it goes and replace any bad parts with PETG in the future.

#6

Totally depends. Maybe it is the brand or whatever, but I wouldn’t use PETG. It is stronger because it is more flexible. Some parts this would be a huge disadvantage, like the XYZ. Depends on you over all use. I designed for PLA and still recommend it. If I were making if for PET I would have made a lot of the parts bigger.

#7

I used the Makergeeks random color PETG sale to build mine, using a 0.5 nozzle with 3 perimeters and the reccomended infills. At 65% infill it’s pretty rigid.

#8

Tom’s video was what I was thinking of: https://youtu.be/CZX8eHC7fws

Regular PLA does gain strength and heat resistance.

Accounting for the shrinkage would be a MAJOR challenge. Plus warpage potential durning the annealing process.