Plastic Management 101
Just a friendly reminder from Makerbot Industries that plastic filament and water don’t mix well. We subjected some plastic samples some very humid conditions, i.e. submerging them in water for 48 hours. Then the samples were used in a plastruder, and checked against a control group. Turns out, the drenched plastic’s performance was awful, the extruded filament being more brittle and even “popping” during prints.
Turns out, the RepRap folks already know all about it:
-from VikOlliver at reprap.org
So now as an added precaution, Makerbot is now shipping all of our plastic in sealed bags with a silica gel packet to keep away humidity. Happy Printing!
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8 Comments so far
Murray
I went to see an injection molder in action and before being injected, the pellets used are baked for a while to extract the moisture they picked up during storage. Water turns to steam making small bubbles and apparently the plastic becomes very brittle when moisture is present.
Torleif
At one time i worked with industrial vacuum forming abs sheets and i remember moisture being of major concern. Blanks being stored i a drive in humidor and stock older than a few months needed to go in a dryer for some hours. I guess some silica in a bag could save allready moist coils.
MatthiasM
Sigh. I wrote this a few times on the mailing list – too lazy to find the actual posts – but nobody ever reacted. Don’t tell me now that this is news
Stephen George
My plastic was bought 2 years ago and pops all the time. Seems to print okay.
I tried putting it in the oven to drive off the moisture but this just deformed the plastic and made it useless.
I was thinking of putting the plastic in the fridge. My understanding is that this is a very dry environment due to the water being frozen and removed from the air.
Just a though is HDPE (used to store milk) hydroscopic?
Is this just a problem with ABS?
Widget
In reply to Stephen George:
Although it is true that a fridge should be a dry environment, as soon as you take out the cool plastic water may condense on it in the same way that water condenses on a cool glass. Because of this, I don’t think a fridge is the best method.
The MSDS I have read for HDPE doesn’t mention humidity under storage procedures, so I’m going to assume it does not have the same problem as ABS.
For PLA I haven’t seen anything relating to humidity, except a caution to avoid direct water damage.
John M
hi,
there is a low budged way of getting your abs to dry.
if you have a central heating system in hour house, makerbot a hanger so you can hang your spindel of abs richt next to the radiator.
this wil provide enough heat to keep the abs dry.
if its realy wet.take a hear drayer and a plastic bag.
put the abs in the bag. make a second smole hole
put the hair drayer in the 1e opening ductape this airight and let the air of the drayer flow over the abs for a 6 to 8 houres.
and you have dryer abs to print stuf.
i am an R&D empoyer of a plastic mold making factory and we produce product of abs.
happy printing.
i realy love this project and i am looking to buy one unit.
greatings John M
Steve J
Funny that it took the Makerbot people so long to discover this.
We just had a Stratasys uPrint installed at our local High School.
The Stratasys rep warned us that the ABS is hygroscopic (note the “g”).
It should not be left out for more than 3 – 4 months.
When not in use for an extended period of time,
it should be stored in special plastic bags that they supply.
Laser Cutting
You live and you learn, you live and you learn. I betcha tons of people will still be caught out over the years when they inadvertently try and use plastic that has reached the expiry date yonks ago, or has been exposed to moisture. You’re only really going to be able to tell once the process gets going, aren’t you?