Deretraction Settings Test

I have a Wanhao i3+ (with Microswiss hotend) which, let's face it, is a positively geriatric printer at this point. It's always struggled with getting clean seams on certain prints after a move, no matter how much or how little retraction I select, or how fast or slow I do it. I had a print where it was particularly important to get it cleaner, so I decided to try and figure out a fix.

I quickly honed in on the obscure "Detraction extra length" setting in Prusaslicer (Printers->Extruder 1), which has basically eliminated the problem entirely. I tried a few values and for me about 10% of the "Retraction length" seems to be the sweet spot. I'm not sure if it's just a quirk of the hotend I have being particularly leaky or maybe the gear slipping or something, who knows, but it's fixed now, woohoo!

One other thing, employing "Deretraction" in combination with "Avoid crossing perimeters" (Print Settings->Layers and perimeters) is basically a no-go as the deretraction occurs after the initial free space travel move, but before the moves within the print perimeter. This is potentially a bug, I'm not sure.

Anyway, this is probably a very niche problem that not many people have (Prusaslicer even says "This setting is rarely needed"), but I thought it worth mentioning.

If you want to actually use this you'll need to force the seam to be on the arc, either by painting it on, or (preferably) make sure the arc is facing rearwards, and set the seam location to rear in the print settings.