[JohnBooty]

Wow, I'm genuinely kind of stunned that others aren't experiencing this problem. I'm not sure why it's just me.

I owned probably 20-30 Frixons over the years, purchased at various times, and nearly all of them had this problem.

The only constant (beside the human being using them) I can think of is that probably 75% of my writing was in Moleskine-brand journals, and maybe 25% on index cards.

[patmorgan23]

Do you live in a warm climate or leave them in the car during summer?

[JohnBooty]

Good question. It happened even with Frixions that never left my house (which is the majority of them) here in the northeast USA. 90F/33C+ days are not uncommon here in the summer, but the Frixion writing in my notebooks ever went "invisible", so I think we can rule out a heat issue.

The ink in most of the pens was still visible and hadn't gone "invisible", so I don't think it was working but laying down invisible ink. It felt like the balls in the ballpoints had locked up.

[astoriafloyd]

You ever try sticking them in the freezer to see if they just heated up?

[JohnBooty]

No, never tried that.

The ink inside the pens could be clearly seen, so I don't think it was invisible. And the ball in the ballpoint clearly felt like it had locked up.