Since the release of the latest Noodler’s flex pens, I’ve had several people emailing me mentioning that they were having trouble getting their new pens to flow properly. They tried shaking, pushing the ink down the feed with the piston, and dipping the nib, but to little avail. Nathan mentioned in a previous video about his Ahab pens that the new feeds on the flex pens may have residual oils from being machined that can cause flow issues. It’s not every pen that will be affected, it seems that most are fine and some are affected.
In any case, it’s a good idea to go ahead and flush your pen out before inking it up, just like I show in the video here. Just use water, dish soap like Dawn, and a bit of ammonia. Flush it with clear water after that, then you should be all set. If that doesn’t do it, then the friction-fit nib/feed may need a bit of adjustment like I show in this video.
I hope this helps! If you have any further questions, just post in the comments or shoot me an email.