I’m always amazed how much this story changes every time I check in on it.

The first rendition I heard, he was selling his land to a company that was going to build a mall. That was going to be a big boon for his automotive & welding shop, as it would bring a lot of new business to the area. As the sale was nearing completion, the buyer revealed they weren’t actually going to build a mall, instead they were building a concrete plant. That would have the opposite result for Heemeyer’s business, so he balked and increased the price. The buyer decided to play hardball and instead used the city council to put pressure on him, which they did by cutting his sewage lines & declaring his property uninhabitable.

That’s a very different story than what was posted above. And it’s fascinating how slowly the narrative has changed. The ‘build a mall’ portion disappeared first. Then the sewage lines were never there, he was always supposed to build a septic tank. The latest addition I see is now he has firearms as well and is shooting at power transformers. I wonder what will be adapted in the next cycle.

I think you already have your answer, but let me elaborate a bit.

The places in the middle where the filament is missing - those places are either dirty or too high.

The area in the back where the filament is sticking, but isn’t filling the area correctly, those areas are too low.

Most likely cause for both is the build plate on an Ender just isn’t perfectly flat. You can try to adjust it to get it closer to being level. But I’ve always found I’ll have sections that just aren’t right. And so, I just don’t print on those sections. Find the areas that do print well, and locate your prints there.

Last note - try putting down a layer of painter’s tape. I find that helps tremendously with both of the points you’re fighting.

So, I’m a novice Linux user and have been on Ubuntu for maybe 2 years now. And I’m just starting to hit the SNAPS wall - IE, just a bit too much of what I want doesn’t install through snaps. Is there a good progression for my “next distro after Ubuntu?”. Still need some training wheels, but ready to take the next step.

FWIW, I bought a new Ender3 as a kit not too long ago, it was $150 IIRC. And by being forced to assemble it, I learned a good bit too. It might be worthwhile to watch their store & see if they put it up for sale again.

The only upgrade I’ve done that I really felt made a difference was buying an enclosure for it. Nothing fancy, it’s a fireproof bag over an aluminum frame. Even more than controlling the temperature, it also keeps it dust free when not in use - that’s probably the biggest win for me.

As for buying the used one - these things do wear down. Start by checking the feed gear & the PTFE tube. If the filament feeds well, then also check the belts, rollers, & nozzle. Those are really the common wear items imo. Perhaps obvious, but make sure the seller gives you a copy of the slicing software (should be free on their webpage) and also the little USB-A to Sim card doo-hickey that you need to move files back & forth.

I have a second hand little portable vacuum cleaner - we used to call them Dust Busters, not sure if there’s a more generic name for them these days. Anyway, because it was second hand, it didn’t have any of the attachments. Was able to buy a bunch on eBay that were sort of close, then 3D print an adapter to make them fit.