PLA Object Is Coating Necessary? Greetings! So after reading about 3D printing for quite some time, I bought a Folger Tech 2020 on Ebay and decided to start off printing with PLA. So, my question is, do PLA objects need to be coated after printing to prevent moisture deterioration? Thanks! ps: printer should be here by Monday so next week will be a looooooooooooooooooong learning week! https://reprap.org/forum/read.php?1,691863,691863#msg-691863 Mon, 14 Sep 2026 14:44:24 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?1,691863,692861#msg-692861 Re: PLA Object Is Coating Necessary? https://reprap.org/forum/read.php?1,691863,692861#msg-692861 Plumguy General Sat, 30 Jul 2016 13:34:09 -0400 https://reprap.org/forum/read.php?1,691863,691919#msg-691919 Re: PLA Object Is Coating Necessary? https://reprap.org/forum/read.php?1,691863,691919#msg-691919
If you want your objects to be water-tight (e.g. a cup to hold water, or lid to keep water out) then you probably should coat them in some way (e.g. paint). Maybe experts don't have this problem but on my objects there are often small gaps between printed layers or at corners that are not obvious to the naked eye, but big enough to allow water through.

I expect that freeze-thaw cycles would break down a 3D-printed object which contained water droplets, although I haven't actually seen any evidence on my garden ornaments.]]> frankvdh General Tue, 26 Jul 2016 20:20:12 -0400 https://reprap.org/forum/read.php?1,691863,691915#msg-691915 Re: PLA Object Is Coating Necessary? https://reprap.org/forum/read.php?1,691863,691915#msg-691915
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Plumguy
Hmmm, so moisture is more of a concern with PLA filament, (such as storage) but not the final printed object?

Hmm, no, moisture will have an effect. PLA will break down in a compost, moisture and heat is what is required to start the break down process. It is of course less of an issue after you've printed.

from what I understand, water in filament will give it a 'honeycomb' effect as water creates pockets inside the filament. I'll have to see if I can find the image, but this is what you start to see under the microscope. These will then 'pop' when the filament is heated, and the steam escapes. This will cause artefacts in the print where the pressure has changed in the nozzle. This is at least what I understand of it.
This process should still happen in your 3D prints after printing, what affect this has is unknown but is perhaps something to consider for mechanical parts and bits in your printer. The new E3D edge filament becomes more brittle if it has moisture in it.

If you are concerned about longevity and/or you want to use it in high moisture conditions than a hard coating is certainly something to think about. Otherwise I wouldn't worry.]]> Origamib General Tue, 26 Jul 2016 18:06:40 -0400 https://reprap.org/forum/read.php?1,691863,691903#msg-691903 Re: PLA Object Is Coating Necessary? https://reprap.org/forum/read.php?1,691863,691903#msg-691903
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Plumguy
Hmmm, so moisture is more of a concern with PLA filament, (such as storage) but not the final printed object?

Correct]]> Mach General Tue, 26 Jul 2016 17:10:09 -0400 https://reprap.org/forum/read.php?1,691863,691898#msg-691898 Re: PLA Object Is Coating Necessary? https://reprap.org/forum/read.php?1,691863,691898#msg-691898 Hmmm, so moisture is more of a concern with PLA filament, (such as storage) but not the final printed object?]]> Plumguy General Tue, 26 Jul 2016 16:33:05 -0400 https://reprap.org/forum/read.php?1,691863,691882#msg-691882 Re: PLA Object Is Coating Necessary? https://reprap.org/forum/read.php?1,691863,691882#msg-691882
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Plumguy
Greetings!
So after reading about 3D printing for quite some time, I bought a Folger Tech 2020 on Ebay
and decided to start off printing with PLA. So, my question is, do PLA objects need
to be coated after printing to prevent moisture deterioration?
Thanks!

ps: printer should be here by Monday so next week will be a looooooooooooooooooong learning week!

Moisture does not have any impact on PLA prints. Not sure if you meant PVA, or if you were thinking of what moisture does to PLA filament, but it is not water soluble.]]> Mach General Tue, 26 Jul 2016 15:32:22 -0400 https://reprap.org/forum/read.php?1,691863,691863#msg-691863 PLA Object Is Coating Necessary? https://reprap.org/forum/read.php?1,691863,691863#msg-691863 So after reading about 3D printing for quite some time, I bought a Folger Tech 2020 on Ebay
and decided to start off printing with PLA. So, my question is, do PLA objects need
to be coated after printing to prevent moisture deterioration?
Thanks!

ps: printer should be here by Monday so next week will be a looooooooooooooooooong learning week!]]> Plumguy General Tue, 26 Jul 2016 14:09:48 -0400