Comment on Should I distill IPA (isopropanol alcohol) at home for 3D-printing?
morbidcactus@lemmy.ca 2 months agoShit just even for filament printing, there’s some solvents that get thrown around online that yeah, you really shouldn’t use in a home setting, it’s really easy to get things like MEK, which work, but starting to get into nasty territory for stuff that will dissolve filament.
Most people do not have adequate ppe or ventilation to deal with chemicals at home, or a fire cabinet, or even know how to find an SDS.
Semi related, lithium batteries are straight up terrifying, primary cells more than rechargeables, but same idea, I honestly hope no one ever gets to experience an actual full on cell failure, I avoided them thankfully but heard stories of just how much energy is released in even one C or D sized cell going.
On the composite filaments, abrasive filament sure sounds like a great thing to make wear surfaces out of! There’s a list if things that idk if I’d print, and that’d be up there, ots oil bronze bushings are like, a buck, maybe 2? And they’ll last a hell of a lot longer.
lithium batteries
People in the office next to mine deal with prototype lithium cells and yeah, terrifying. They charge them in a special fire cabinet in case they go pop, and have buckets of sand everywhere (although the official advice is to not bother, gtfo). If you plot energy density on a line, there is an overlap between the highest density lithium cells and lowest density high explosives
EmilieEvans@lemmy.ml 2 months ago
Most people are moving torwards glass- or carbonfibre filled materials for one reason or another (e.g. asthetics). If the 3D-printed part contains a bushing than it is the same material. Often it is enough to just stick a metal rod through it. No need to worry about sourcing and installing bushings.
Also for the Igus materials (e.g. Nylon with PTFE) it is a composite. Anyway. If you have a real need for a high endurance than you can’t 3D-print. Injection molding is king and if this isn’t possible at least use a hybrid manefacutring (additve + subtracte) to get the appropiate surface finish and tolerances.
morbidcactus@lemmy.ca 2 months ago
Was more a thought about if you are concerned about micro fibre particulate (what I took from your post, sorry if I misunderstood) plastic on plastic or plastic on metal are fine for sure, maybe a little exaggerated. Do wonder though about the wear of 3d printed bushings, surfaces won’t be smooth, some of the glass filled nylon I’ve used has almost a soft surface to it, it’s really hard to describe, some post processing though would probably make my (mild) concern moot though so.
Wrt composites hobbyist/prosumer grade manufacturers (some that target engineering customers in that bucket too) claim they don’t experience the same warping or shrinkage in general, whether or not that’s true I don’t have enough information to tell you unfortunately. Have found both common types definitely have more rigidity, I use them in places where that really matters.
It’s pretty common to see cheap bearings in 3d printed parts, actually mildly interesting to me that bushings don’t seem to be, at least at the hobbyist level. To go further, how many designs do you see with heat set inserts or pressed in nuts?
EmilieEvans@lemmy.ml 2 months ago
Heat set inserts are an interesting topic. You don’t need them if the screw is only installed once. Sure enough you can drive a metric screw into a 3D-prind and form/cut the threads but better are self tapping plastic screws. For nut vs. insert: It depends. if you can get away with a square nut (e.g. DIN 557 | don’t use hex nuts like DIN934) they are quicker to install. Make the cutout slightly undersized so the nut is fixed/wont move when the screw is installed.
If you use inserts consider the flange type to get a very nice aesthetic: e.g. de.aliexpress.com/item/1005006135129074.html
Removable plastic rivts are also a great fastening option. Push pins with integrated spring are equally briliant. Parts with snap fits are awsome but very diffuclt to design as the tab needs to flexible to be pushed in place but still strong enough to not break (layer adhesion).
Warping is indeed a big selling point for these materials. Major selling point/driving force I belive is still the esthetics of them as they provide a surface finish which can be sold (without post processing) without looking like a FDM 3D-print. Less warping, improved properties is more of a nice to have for most applications.
This can be sad about a dozens of constructions. ISO1234 /DIN91/GB91-2000 splints are everywhere in the industry but nobody in the hobby space knows about them.
For bushing vs. bearing: It always depends on the application and industry.
Talked a while ago to somebody that run studies on FDM printed bushings. The verdict was that print orientation/layer adhesion was a limiting factor with their setup.