Hydration Issue with Taulman Bridge Nylon

[GammaRays]

I recently purchased Taulman Bridge nylon filament and have been having some issues with hydrated filament. The plastic bag the filament came in was torn when I received it, so I knew it wouldn't be dry enough to print with yet. I tried anyway, and noticed a lot of steam and a pretty awful print. After that, I followed the directions on Taulman's site to build a dehydration chamber. I put my filament in the chamber for 6 hours at ~145 F and did a test print. The print turned out to be about 80-90% of the quality I'd assume it should have, but there was still plenty of steam coming from the extruder nozzle. Lastly, I put the filament back in the chamber for 6 hours at ~150 F and did a test print. The steam still hasn't subsided and I'm wondering if it ever will.

Is the filament I received just a bad batch that had been in a ripped bag in Amazon storage for too long, or do I need to dry it for longer than the 12 hours I've done already?

[Alibert]

The best way to dry filament thoroughly is use a vacuum chamber at 70 C / 160 F and pressure down to 50-100 mbar. That way you are below the boiling point of water and nylon dries out fantastically well.

I built my own vacuum chamber similar to these: http://www.bestvaluevacs.com/aluminumchambers.html using chinese parts (-950 mbar vac pump, manometer, taps, silcone heating belt, PID controller) and a 1" thick piece of perspex and a 10 litre aluminium soup pot. As gasket I milled a 3mm deep ring in the perpex with my dremel and poured a hard silicone rubber into it.

The whole setup works very well. A few hours is sufficient to get the most humid filament totally dry.

I have a test print where the test piece is snow-white and rough with lots of tiny (burst) bubbles, and the dried filament gives a near-translucent smooth result after vac-drying.

Cheers, Albert.

[jimc]

i have used a vacuum chamber with good results but also the oven works just as well. i have 2 rolls of bridge here and your right it is a $itch to dry it out but when its dry it will print basically steam free. it will get wet again though if left out just for a couple few hours. i dried mine so it was perfectly dry then put it in a bag with about 30 bags of silica gel and it still sucked in moisture the next time i went to use it. when i dried it it was probably around 150-170 for 3-4 hours and it was good. did i mention i hate nylon. its just a pia no matter what.