Moisture in ABS close up of the results

I was changing filament today and when I was flushing the old color out I noticed the new color felt rough so I thought I would show a photo for those that don't know that moisture can be a problem with ABS filament.

This is a 50X microscope view or silver ABS extruded with a .40mm nozzle. You can see all the pits in the surface and while this would print, it would not be a silky smooth print like I normally get.

Fix? Well I have a highly calibrated convection toaster oven I use to use for another purpose. I put the filament roll in it at around 65c for an hour or two and it will dry it out without melting it.

wow, never seen that with the 60Kg of ABS I have run despite not always sealing part used rolls into airtight bags.

Curious what you general ambient humidity is?

Our humidity is around 50% most of the time. You cannot see the damage with the naked eye but the extrusion feels a bit rough. It takes a lot longer for it to affect ABS than PLA but it can.

2 hours of drying later.....

Nice before and after comparison - thanks!