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You’re telling this as a funny story, but to an outside observer that sounds horrifyingly dystopian. Someone improperly reported you like they were getting side-pay by the Stasi and four armed government agents showed up at your door to accost you over a personal possession within your own home. Absolutely nuts, and ironically why many people consider personal firearm possession essential to freedom.

agree, from an european POV this story sounds crazy and I would be afraid to even invite random people inside my house for fear of repercussions that I'm unaware of.

edit: apparently this didn't happen in the USA?

I just looked up your printer and it looks extremely similar to the one that I have, which is the Creality Ender 3. Both appear to have an identical stock plate, which makes me think your base adhesion problems will almost certainly be addressed by switching to a spring-steel PEI plate. Although I didn't start having problems after only a few prints, the stock plate on the Ender 3 actually worked too well for me which often caused me to need to use a tool to pry and scrape prints off which resulted in damage and reduced adhesion. I switched to the PEI plate and all my problems related to adhesion went away. It's smoother than the stock plate but somehow PLA sticks pretty well to it, yet not so much that I can't easily remove prints with my fingers. No glue stick or hair spray needed so far.

3D printers really aren't good toys in and of themselves. They're fun for a little while and then you realize you don't need that many plastic doodads. But mine's been very useful for certain projects where I need to build custom parts. People sometimes forget that these printers are just tools like anything else. Fortunately they've become so cheap that it's not really that much of an expense to find that out for one's self.

EDIT: Seriously, anyone with adhesion problems should get a PEI plate. I have had nothing but success with mine and I don't know why these printers don't just come with them in the first place.

All Good tips, thanks.

I think I would get more use out of it if I acquired some basic CAD skills!

If you can code, OpenSCAD might be the best place to start. I have 3D modeling experience, but CAD is sort of a different beast and a skill of its own. Most of the free tools that exist are pretty complicated (FreeCAD makes me want to claw my eyes out) and the professional software packages are outrageously expensive. Once I found OpenSCAD, which is basically just modeling by code, I got way more use out of my 3D printer without just relying on other people's models. There's even an extension for VS Code that allows you to use it as an IDE for it with previews.

This isn't to say that you can't take the time to learn more standard CAD software, but for what I'm doing I haven't had the time for that and I imagine you probably don't either. After a few hours of learning OpenSCAD and reading the cheat sheet, a whole world of possibilities was opened to me.

I would love to use OpenSCAD, just seems to have a really steep learning curve that I can't get up. Even though I write code professionally and have no professional CAD experience, Fusion360 just clicked in a way that OpenSCAD didn't for using my 3D printer (Prusa Mini).

I agree about FreeCAD, lacks a lot of polish, but there's a big update coming from it seems basically one maintainer that looks pretty promising. I found it looking for a way to save in a git-sane format (which this branch/fork has). Main problem with Fusion360 (for me) is the lack of Linux support.

I haven't used Fusion360, but I have to say the screenshots of the UI make it look appealing and pretty straight forward (more so than say Solidworks).

My assumption is that it and other standard CAD packages would have a greater learning curve for a programmer who mostly wants to print simple but custom objects. Granted, I have a background in non-CAD 3D, but OpenSCAD was incredibly fast for me to pick up not just because it relies purely on code but that it eliminates a lot of concepts that you are forced to learn otherwise.

In OpenSCAD, there are no units (though STLs seem to come out in millimeters), no object hierarchies, no sketches, no key combos, etc. All you have is code, in a domain-specific language, that describes what is being built. This can be difficult or unappealing, especially for someone who isn't a full-time programmer, but it can also be freeing to just deal with code and not have other things potentially get in the way or cause confusion.

Of course OpenSCAD probably doesn't scale the more complicated a project gets. But for Arduino/RPi boxes, replicating parts, screws and bolts (given a 3rd party module), it's a powerful and handy tool. However, it might be horrible for someone with limited coding skills.

Fusion 360 is pretty easy and fun to learn. I became productive in it within just a couple hours, and used it to print some things for some house projects. Just my $0.02.

Nice. I'll have to give it a try!

I've also a programming background however I got very intimidated by openSCAD though I think that might've just been because I had been using tinkercad for a year an a half beforehand and was just coddled.

OpenSCAD's biggest problem appears to be that it is single-threaded. I learned this from a guy printing parts for my RV. Is there an open CSG package out there somewhere that does operations like Minkowski Sums as convolutions so that they can be expressed as multiplies in frequency space and then brought down to real space for tessellation? Not only could you take that multi-threaded but you could potentially run it on a GPU hundreds of thousands of times faster.

I started out with OpenSCAD but found it limited me eventually with some of its lack of advanced features, probably because it focuses on solid geometry. I recently switched to CadQuery which uses the same CAD kernel as FreeCAD and haven't looked back. It's also Python rather than a domain specific language.

I would like to add onshape has a good free plan (your designs will be public) but it is a great midpoint between tinkercad and full on CAD.

+1 for PEI base, although it doesn't have to be spring steel. I ran a print farm years ago and used PEI sheets on top of the stock beds. You can buy them cheaply on Amazon with adhesive tape, cut them to whatever size you need, and adhere them right to your existing base plate.

Although I fully agree with the second part of this comment as well - these days I only print a few things a year for custom projects and generally find that making items primarily out of wood and metal with a few plastic parts is a lot more satisfying and useful.

Could this have been a good cop / bad cop routine? Officer 2 was encouraging you to break the law. It is an offence to manufacture, import or sell a realistic imitation firearm, or to modify an imitation firearm so that it becomes a realistic imitation firearm.

Where?

Making guns at home is as American as apple pie.

They're either in the UK or Germany. But I suspect the UK.

Is there some reason you assume "American" by default on the global information superhighway?

This story can’t have happened in the US

I had a similar experience where my first few prints worked great, and then had bed adhesion trouble. It turned out the filament had absorbed water from the air, and drying out the filament solved it.

Have you tried covering the build plate with a glue stick? Always worked for me, at least for PLA.

I have heard of this and it is on my list of things to try. It seems counterintuitive to me that the glue wouldn't simply become a runny mess. Thank you for confirming it works. Just confirming we are talking about 'Pritt-Stick' when people say glue stick, are we?

Yep, that's what I've used with success as well

I use elmers glue sticks (the purple ones which dry clear), but Pritt should work as well. It's slightly messy, especially since the purple color comes back if you wet the surface. Then again, this helps to make sure you got all of it off. The underside of the print is slightly tacky, but nothing a wet paper towel can't fix.

Borosilicate Glass or PEI with spring steel backing (if your bed has the magnets vs the build surface having magnet material) work great in my first hand experience, both will give a much better surface adhesion than most others.

Another cheaper option is G10 or FR4. I've got copper backed FR4 on my list of things to try. Apparently it has a more even heating due to he copper against the heated bed. I've been using the glass held on with Binder clips until recently when a few binders popped off and tossed the whole lot on the floor of my garage sending shards everywhere.

Excellent tips. It is the build service that is magnetic I think, but I guess you could glue something similar to the glass...

Pritt-Stick works, but I have yellow painter’s masking tape on plain sheet of aluminum. Bed’s not even particularly flat, but works for me, no mess.

Couple things that comes off my head that caused my “adhesion problems” over past years were incorrect Z=0 height, uneven bed, rigidity issue on moving bed, and worn out nozzle. Worn out nozzle is easy to spot, if your extruded material curls up before dropping down, that nozzle is done.

It had been more often an excessive or uneven force forcing print to depart from bed, than print simply detaching for lack of reasonable adhesion.

Also, a last-resort workaround is to put the model in the air so first 5mm(1/4”) or more is just supports. Support material is more tolerant and top of it is naturally more flat and parallel. Downside is that the bottom of the print looks just bad.

Do have a glass cover, so you can just take it out and wash (and also have no problem with scratching).

Anyway, a heated bed is much more impactful than the bed surface. Glass at 60°C alone is enough for PLA (with glue it adheres too well and stops working again), while you will need both a heated bed and surface covering for ABS.

Also, any PVA based glue works. If you dissolve some white glue and spread it through the glass, it works even better than solid glue, but it's much more work.

This usually has the downside that you have to clean/wash the plate after a few prints, as the glue otherwise accumulates to a height that interferes with printing.

is that a normal experience in all of the US or only certain states? sounds all kinds of fucked up. the random passerby ratting you out. cops showing up over a handgun, which as far as I know are legal to own in all states unless you're a felon. doesn't sound like land of the free at all.

Don't think op is in US. Nobody would say "phone engineer" in the states.

Come on, this sort of cop behavior is limited to the US

That’s easily the most naive thing I’ll read today.

Not at all, as I mentioned above I am in the UK. It is hard to get our police to react to anything...but any mention of firearms gets them excited. Interestingly I thought the phone engineer was more of a dick than the coppers.

Lol you’ve been shown to be wrong by the original commenter. Get your head out of your ass.

I'm also (as well as OP) in the UK, but mildly disappointed to read it on HN. Bit of a pet peeve of mine (as a capital E Engineer I suppose) the absurd things we accept having 'engineers' sent out for, things that are barely even trades.

I had a dishwasher engineer fit a replacement plastic piece where you put the tablet; a quote for an oven engineer to replace the glass door.

That sort of ridiculousness makes me more sympathetic to bonafide tradesmen using the term (or rather having it used about them by customer services) - boiler engineers, ISPs' 'engineer visit' to set up a new line, etc. - despite that probably being what started my peeve initially!

I don't know how widespread it is, I know in Germany for example it's a protected term. In Canada I think if unqualified (i.e. not 'software engineer' or 'boiler engineer', but just 'Engineer') it is too. We have chartered institutions that can bestow 'CEng', but it doesn't affect whether or not you're allowed to be called 'an engineer' or anything.

(This whole comment probably makes it sound like I'm a lot more annoyed by it than I am.. I just mean it's sort of 'heh ok sure' chuckle/eyeroll when they say it. Like if it started to be normal to refer to pharmacists/nurses/phlebotomists as 'dispensing/assisting/blood-taking doctors' I suppose.)

Perhaps we have it backwards. I'm in the UK. If I saw a company that did 'engineering' I would expect to walk in and see someone at a lathe. I work in the West Midlands a lot and this is especially true.

An engineer may drive a train or maintain ships propulsion in the English speaking world.

A Civil Engineering company builds roads and bridges, and may not have any Chartered Engineers on the staff.

I know several people who design electronics for a living, have degrees in the same subject and call themselves 'Electronic Engineer', yet becoming CEng would never cross their mind. Whereas if you wanted to become a structural engineer you would likely have to become chartered.

I have never met a Chartered network engineer, yet what else would a CCNA call themselves?

Never mind the software engineers and Devops engineers...

Perhaps the Chartered Engineers should have found their own term rather than adopt a general one and then get sniffy about other uses? I know the Chartered Institutes have been around a long time but the term 'Engineer' predates them by some years.

Yeah, maybe. But that's what I mean about 'barely even a trade' - takes a lot more know-how to operate a lathe (per your example) than to do a lot of the 'handyman' type jobs that we get told 'an engineer' will be sent out for.

Fwiw I'm not CEng, EE by degree, but work in SE. I'd like the IET & chartership to be more relevant for SE, but all I meant by that was that we have it, but don't (as some other countries do) require it or something like it in order to use the term 'engineer'.

I was reminded on the tube this morning that this same sort of thing gives us TfL's 'Network Presentation Team' - née 'cleaners'.

I thought wow some guest working at Apple snitched on your kids?

Story was not from the US as there is no “section 1” prohibited firearms. Maybe Canada?

I'm in the UK, should have said. There are almost no authorised civilian uses of handguns in the UK since the Dunblane shooting. I think you can have one for humane despatch of deer (subject to extraordinary proof of need), but that is all.

https://en.m.wikipedia.org/wiki/Dunblane_massacre

>I'm in the UK, should have said

No. Fight the American default!

> It stays pretty calibrated but I have struggled with base adhesion once a few prints have been through it.

Try using a heated bed and enclosing the printer in a chamber to prevent draughts (anything will do, cardboard).

A heated bed and IPA work for me.

I do have a heated bed. A cabinet would be nice as protection for the printer as well. One day!

For what it's worth, my Prusa doesn't have any issues with adhesion (heated bed, occasional clean, no cabinet). It could be a calibration issue (the Prusa does self levelling which might help?) or a slicer settings issue, not sure. Anyway, it is possible to get repeatable results.

pretty sure you weren't "arrested"- ah you said you're in UK, not the US.

Well he said the words, 'I'm arresting you on suspicion...'. He later 'de-arrested' me. He also told me that details of my arrest would remain in the Police database... which is nice

Can't find funny bit in "funny story." *looks around nervously*