RE: Stubborn PLA bridge artefact
You're a bad influence! I've now spent several days fooling with settings and have come full circle to about the same settings you were using, with similar results. I'm starting to think that the bridge strategy used by the slicer could have a few more settings. It's possible that the flow takes a bit to stabilize when the bridge starts at a new speed. Possibly there should be an option to ramp the speed at the beginning of a bridge. I could see having a delay and even a dedicated nozzle temperature just for bridges. I'm using a high flow nozzle, but I don't think that makes much difference. Oddly, many things I read online don't hold true here. Cooler isn't better and the flow has to be up around 1.75 to 1.85 to avoid gaps. I find 25 mm/s is as good as slower. What I thought was uneven spacing (pairing) seems to be a slight vertical height difference that's mostly visible from the top.
What bothers me most about the bulge is what will happen with the next layer if the nozzle hits, so for most things I'd probably use setting that keep the bulge down, even if that means some gaps. Hey, they'll get paved over on the next pass!
I know I won't be able to leave this alone, so let me know if you learn anything else.
RE: Stubborn PLA bridge artefact
Can't leave this alone but have come around to about the same setting you're using. I'm thinking the slicer may need a couple more bridge-specific tuning settings. Let me know if you learn anything more.
RE: Stubborn PLA bridge artefact
Sorry about two posts. This site can have a several minute response time, tell me it timed out, then add my "lost" post much later!