Perhaps, but have you actually tested this for yourself?
PLA is extruded at 220C in my Prusa beastie. Once the filament is slapped on the model, I probably want it to to fuse to the previous layer really well and then cool really fast and become stable.
We need to provide working and results rather than “I think that”. My printer is quite close to a very large double doors to outside, which open and shut as required.
It’s complicated but PLA is bio-degradable … eventually. Not months but years. That’s much better than the horrors you see on Blue Planet II.
Plus humidity is bad for your filament.
I keep on hearing this but it does not check out for me.
I have a Prusa 3S+, self assembled. I do not do a great deal of printing and go through phases. I did a flurry of prints during the pandemic and then it rested idle in our rather cold and slightly damp study for a couple of years. When I bought it, it came with a spool of silver Prusament which worked nicely. I then bought a spool of “Sunlu” filament (Chinese firm off of Amazon) and then a box of 10 colours of the stuff.
I recently got the printer out and updated the firmware, re-calibrated it and so on. I’ve done several prints with filament that has been open to the environment for at least two or three years and its fine. I have done a print using some transparent filament which was unopened and that was fine too. The unopened stuff was vacuum shrunk wrapped so could not possibly be damp. The opened filament was stored in the original cardboard box in a slightly damp and unheated room.
For me the main issues for a decent print are:
I will try repeating a challenging print with filament that is way older now and see what happens. I printed a couple of tank models in red around four years ago. Both involved their turrets with the barrel facing upwards - that’s a lumpy cylinder about 4cm long and 2mm wide.
I have seen some notes about PLA being hydrophylic (absorbs water) on the Prusa website’s official advice but I don’t personally think it is an issue and people are probably missing another factor or factors that is fucking up their prints. I think the filament dampness meme is “cargo culting”.
PLA is heated to around 220C whilst being extruded so any water will steam off very quickly as water vapour - which is not even “wet”, well before worrying a print job.
PLA is touted as bio-degradable and it is … eventually. It is extremely stable, despite being derived from corn starch. It really doesn’t seem to care about a bit of water hanging around. That’s why I can print new hinges for a plastic garden storage thing to replace the original ones and they last through winters and summers in the UK.
So, if you think moisture is an issue for PLA filament used for 3D printing, why not do some experiments and then decide for yourself.
I’m happy to be proved wrong.
That is superb. Sadly my eyes degrade faster than the frames wear out!
I see you are on the John Lennon specials which makes it a bit easier to model. I haven’t worn circular specs since college (~1990) My current Tesco specials only have lens frame from the nasal bridge clips, over the top to about 5mm below the temple joints.
Just a thought but you might like to investigate using spring steel for the arms and PLA just for the frames. You could create a jig for joining and heat the ends of the arms up with a brazing torch (kitchen supplies) and sink them into a suitable cylinder close to the temple joint. If you go all in you can make the straight part of the arm rigid and the over ear part flexible with careful heating and cooling and whacking with a hammer!
Now, that metal work will be comfortable but might be a bit chilly. What about PLA tips over ear instead of steel?
Anyway, great job. I’m very impressed.
In Australia, it’s the other way around and the clock will try to eat you or at least sting you to death.
So where do you put the rest of your helices on a cylinder or cone, in 2D? In Flatland a screw or bolt becomes a circle with a short hair. The whole point of “leftie loosy” is to try to help with reality as we perceive it.
Try it the next time you are underneath a car wielding a socket spanner with a taped on extension thingie that you jury rigged whilst trying to shift a hex nut at 45 degrees to reality that you cannot see, with oil dripping in your eye. Obviously the oil is a mix of the 30 year old native stuff loosened up with the WD40 that might break the rust lock.
I suggest you do think abut things in 3D and don’t forget the other dimension (time). That WD40 needs time to break the rust lock.
“Leftie loosy” isn’t for keyboard worriers - its for engineers and technicians, plumbers, and the rest and obviously for DiYers.
When you are knackered and pissed off and you need to shift a fucking nut or bolt or whatever, you need incantations to get you back on track.
Apple: User - you are holding it wrong!
The spanner is always at 12 o’clock. Either turn yourself or the spanner or your point of view to make it so and then the rule holds. The last option require imagination.
Take the piss after you have tried to thread a nut on a bolt that you cannot see and tightening it is towards you, at an angle. The nut has to cross a hack sawed thread and will try to cross thread 75% of the time unless the moon is in Venus.
Have a chat with some plumbers, builders, chippies, sparkys or engineers - assuming you are not one already. I think “leftie loosey …” is well known in the UK.
“warm up the sauna”
I get slapped when I try that sort of thing on with Sauna.
They are not a circle unless you have some really odd bolts or screws! I suppose a bolt looks like a circle in “Flatland” but we live in 3D space with time as a fourth dimension that we can directly perceive.
A screw or bolt and the rest are, roughly speaking, a cylinder with a helical thread on it. They also have a “head” or similar which acts a stopper. You can model all of them as a bolt. We use a spanner, wrench, fingers, screw drivers, drill drivers, scissors, whatever to do the tightening or loosening. You can model all those tools as a spanner (wrench). We need some final mental contortions to make this slightly rigorous: The spanner (wrench) is always considered as being at 12:00 on an imaginary clock and we have to assume that our bolt moves away from us for “tighten” and towards us for “loosen” and I suppose we should also require that we are looking at the “face” of the notional clock and not its obverse!
Now it should be obvious how the rule works. Turn the spanner to the right and you tighten the bolt, turn it to the left and you loosen it.
OK that lot is not very helpful when you are under a sink or in a roofing void performing strange contortions. Try holding up one of your hands and pretend you are holding a bolt or the head of a screw. Clockwise turns will tighten and anti clockwise will loosen. You might use “leftie loosey …” to bootstrap: “clockwise tighten”. It becomes even more interesting when you are trying to work out which way to turn a bolt or whatever when you can only feel it and when tightening actually moves it towards you.
Think about a bolt running through a wheel with the head towards us, say on a very simplified bicycle. Move the bike to the right, and hence the wheels turn clockwise. Friction should cause the bolt to tighten. If you change the design and put the bolt in on the other side and now forwards for the bike is to the left then you will loosen the bolt and that will be dangerous. Now change the design to a bolt with a nut and washers etc and it rapidly gets complicated!
Also, please note that some bolts have reverse threads to the norm. On a garden strimmer the tightening knob that holds the spool on is often a reverse threaded bolt. That’s for similar reasons to the bicycle wheel thing I mentioned earlier.
I’ve just spent ages and a lot of words to try and persuade you that this has bugger all to do with autism. I think that your error was really to do with not thinking too deeply about the real issue and focusing on the wrong thing. We all do that, extremely often, regardless of where we are on the spectrum.
I hope that you see that considerations with regarding helical threads on a cylinder or a tapering cone (but not circles) can be quite complicated and that’s why sometimes we all need some silly rules to get us through the every day ordeal of dealing with them.
Now, would you like a chat about circles … 8)
La derecha oprime y la izquierda libera
I just knew that would be Spanish, without being able to speak more than a few words. It works far better than our effort and is both a sardonic and satirical political comment.
Well played Spanish if that really is the equivalent in common usage. Our effort sounds like it was invented by a young child whilst responding to a BBC quiz.
I’m not feeling too genocidal at the moment and I’m not too sure what a big blob of capitalism looks like but it sounds like you are impugning me (int al) in some way.
If you are going to deliver a stinging attack on something you dislike, why not deploy an impassioned and pithy argument rather than … that. You do at least manage to spell it’s correctly, which is nice.
Good skills Sir! Advice noted and I will re-evaluate how I do specs.
Thank you.