1 Topic by tealvince

  • tealvince
  • Member
  • Offline
  • Registered: 2013-01-16
  • Posts: 319

Topic: Extruding in humid weather

Can humid weather (rain outside) result in brittle ABS filament?  Yesterday, I couldn't seem to extrude for more than a half hour without getting a break while winding.  Looking up close, it seems that the resulting filament has imperfections so I presume this is due to moisture.  I also opened a new container of pellets but they were in a sealed container with dessicant packets.

Also, if I chop up and reextrude, do I need to dry the resulting filament or would the previous water already be expelled? If so, what is recommended?

2 Reply by elmoret

  • elmoret
  • Filastruder
  • Offline
  • Registered: 2012-10-11
  • Posts: 6,048

Re: Extruding in humid weather

Yes, moisture can definitely cause brittle and bubbly filament. The moisture is likely gone from extruding once, but it doesn't hurt to dry them further. Most folks use a food dehydrator, they're pretty cheap from Goodwill or similar.

Filastruder - the robust, inexpensive filament extruder
E3Dv6 All Metal Hotend - the premier 3D printing hotend

3 Reply by tealvince

  • tealvince
  • Member
  • Offline
  • Registered: 2013-01-16
  • Posts: 319

Re: Extruding in humid weather

elmoret wrote:

Yes, moisture can definitely cause brittle and bubbly filament. The moisture is likely gone from extruding once, but it doesn't hurt to dry them further. Most folks use a food dehydrator, they're pretty cheap from Goodwill or similar.

Thanks.  Drying in the oven seemed to help a lot. I still get enough periodic flaws in the filament though (visible while extruding) that it sometimes breaks when coiling onto the spool.  This seems to be much worse when using masterbatch.  I'm using black from OSP, which I was using at 50:1 and improved when going down to about 80:1.  Is this normal?  My colored filament has always been a little brittle before and sometimes broke when manually winding, but it's a bigger issue with an automatic winder since I have to stop extruding when this happens.  I'm going to add a cutoff switch when a break is detected, and maybe switch to a spool with a larger inner diameter and change its orientation so it matches the natural curl when extruding.

4 Reply by elmoret

  • elmoret
  • Filastruder
  • Offline
  • Registered: 2012-10-11
  • Posts: 6,048

Re: Extruding in humid weather

Yes, that can happen with masterbatch, especially higher concentrations. The pros extrude once, pelletize, and extrude again ensuring the colorant is every dispersed. If evenly dispersed, the plastic stays flexible. It is at the concentrated points that the filament is most brittle.

I just tested some 1.75mm natural (no colorant) MG94 ABS that was extruded without much care for moisture, and I could curl it into a 1" diameter circle without breakage.

Filastruder - the robust, inexpensive filament extruder
E3Dv6 All Metal Hotend - the premier 3D printing hotend