The person who said they put their ABS in an oven, believed that just getting to temp releases much of the moisture. That was first and second level release of absorbed h2o.
But without flow thru dry air… the filament does the same thing as the dessicant pack does. Pulls it right back in and quickly too.
And keep in mind, I did not see their process. And shouldnt project my interpretation of what they did. I am guessing. I try to help, not judge. We work together here, and as humbly as needed to want to try again tomorrow on this great team.
In industrial settings, dry-gas-flow-thru is the only kind of drybox i know of used on the production floor, like for creel houses [the box that holds the spools that are feeding the hot end or the laminating machines or injection molding extruders]. These ALL need flow through dryboxes. Designed to leak a little all day. This setup DRAGS molecular water OUT better, and much quicker and it cannot reabsorb.
And in a few cases, like my lab, for dry box storage, we just fixed this with compressed air tube [pin valve as regulator] with a CaSO4 [drierite] dessicator on the feed tube. Cheap confidence. The box is most of the cost. Pin valves are hard to find but old pressure regulators have one.
Flow thrru Drybox seems like serious overkill for us.
It is.
But at work, we do it coz pesky problems crop up almost every day. And just removing one of the most COMMON causes of plastic and prepreg problems was SO CHEAP… there wasnt a good reason to NOT do it. The confidence is worth it. The price is low for any single machine or instance. Is it different here? Yes. But not so different, that a drybox isnt recommended by me. I know we are mostly good with dessicant bags. And I defer to local experience. And im willing to put some scratch in to match funds to help relieve sticker shock.
Can we do a small demo version in another room… before going to the trouble to pipe in compressed air to fablab? I think so. I regard that piping as THE most likely obstacle to getting a flow thru drybox in fablab. [I have a cheap compressor at home. And HATE the noise level of a hundred dollar unit.]
This was part of my job for 23 years all over the plant. Analyze, measure trace water [or oil], show correlation with detrimental affect on finishes or bond quality, etc etc. I wish i had access to the analyzers again. NIAR can test for us, but at $375+ per analysis, its expensive, and we might need quite a few of these tests to prove what the level bedeviling us is. Or isnt.
And if we set fablab up to do one machine for ABS or PC printing… you may as well keep all the spools dry too. Etc, etc. The scope creep sounds awful. Until you check the “per item” divvied up cost. Its amazingly cost effective. Once you have a drybox setup. And are covering all spools and printers.
Yes, we CAN get by on dessicant bags. We are unlikely to be visited by a small mob of members demanding we do this. Just to match industry. Im not in that mob, but still, I recommend this, just for the confidence. And because we dont yet know how to identify when we are being affected by trace water. Should i plan to do some “waterlogged filament prints”? A wet rag in a filament bag for a week would do it. Print a benchy on a slow print. Then do one fast? Or better yet, do vase mode with and without waterlog to help show “affected surface”.
How can I help hang the bell on the cat?
I will.
Right now, i just wish to help guide. Thats my persistent assignment, wherever I go. I wont lead you astray out of pride or profit. But im no savior either. Problems will still happen. Even with dry filament. Dry material and process will likely reduce just a few problems.
But we dont know for sure… and likely never really will- know for sure, when or if to graduate to dry box storage and creel houses. We just know that mostly we are ok, as we are. With dessicant bags.
We wont know how many times a [filament feed] problem, or first layer failure, or surface blowouts is coming from trace water. Until afterwards and then see a reduction in problems. Maybe we will see it. Maybe we are ok.