Comment on Newbe advice
Guenther_Amanita@slrpnk.net 3 months ago
Polyamide is a huge pain to work with. It absorbs water like hell, warps, needs high temperatures, and post-processing is hard.
Did you consider using PETG/ PCTG? They are also very strong, don’t absorb water nearly as much, are easy to print and are UV resistant.
Do you already have experience with CAD modeling? Most programs are Windows only, and the only “good” software I found is Onshape, which isn’t FOSS.
As for cad. I have lots of experience with blender. While it is not designed for true cad. It is very capable of the levels I need.
Also, FreeCAD has grown hugely since I last looked into it. So way more practical to use if I get into anything more complex.
HumanPenguin@feddit.uk 3 months ago
PA6 nylon is the best for strength and chemical resistance. As some parts need to survive in bilge water for a decade or so. Diesel oil will rut them. Nylon plastics are best for this and heat resistance from hot engine. As parts will be used their as well.
Yeah I know it is one of the hardest to work with. Hence the tent and dryer comment.
Would be fantastic if someone with experience in it can tell me if the tent solution is good enough.
Worst comes to worst all have to build a frame enclosure, and it is only a few parts where nylon is required. So I can learn.
The fact that the neptune is able to print at the temps needed is one of the reasons I am considering it.
morbidcactus@lemmy.ca 3 months ago
PETG is supposed to be petrochemical tolerant AFAIK, it is far easier to print and isn’t as bad wrt Air Quality (Most filaments aren’t the best to be around, PLA and PETG are nicer relative to others, ABS is nasty, nylon is really nasty, lots of fine particles and stuff if I recall, I have recirc filters on my printers and they live outside of the house)
That said, with an enclosure, a proper surface and bone dry filament, I found it to be a really nice filament to work with if you prep for it. It does have more shrinkage than ABS, I redid a lot of my hotend in PA6, was very tight in some places and a bit of a hassle to reassemble the first time, otherwise I really like it. I have an in country vendor that I usually source from, but the Glass Fibre PA6 that polymaker makes is REALLY nice to work with, found it has substantially lower warping than standard PA6, there’s also low warp varieties you can look at.
Bed:
I use a Nylon Surface from a company called BuildTak, I hate to recommend brands but seriously, their surfaces are crazy good for adhesion, maintenance is a quick wipe with alcohol and that’s it. They’re also replaceable, peel off the steel backer and reapply.
I’ve seen mention garolite sheets as a fantastic surface for nylon (I think the BuildTak surface I use is a garolite sheet with their adhesive treatment, when I replaced it last time it’s definitely some sort of fibreglass laminate so wouldn’t surprise me). They’re relatively inexpensive, a ~1.6 mm thick ~305x305mm sheet 1/16" 12"x12" is $14.50 usd on McMaster-Carr, but there’s definitely 3d printing specific sheets out there.
There’s the tried and true glue stick treatment, when I had a glass bed like a decade ago it was the only thing that consistently worked, I tried PA tape and masking tape, glue stick just works and makes it release easier, apply carefully and let it bake, if you’re not even it’ll lead to some ugly bottom surfaces, but I can live with that for functional items.
I found Nylon doesn’t like to be “squished” as much as other filaments, I have my klipper setup with a slightly higher offset on my nylon sheet because of that.
Enclosure:
If you do go Nylon, use an Enclosure period. You need heat to help with warping and you ABSOLUTELY don’t want to be breathing it in, it doesn’t smell but gives off a lot of microparticles. As I said above, I have recirculating charcoal+hepa filters on my printers. I’d highly recommend you don’t print in your living space if at all possible. I ran my bed at 100c last time, 100-110c is pretty common, I’d give it a nice long heatsoak, I tend to do at least an hour for larger prints in materials that warp.
Honestly, I don’t find nylon that fussy, like anything, prepare for it and you’re good.
bigredgiraffe@lemmy.world 3 months ago
I have printed PA and tent idea will probably work but the other person is not kidding, PA is very finicky. Plan on printing PA directly from a dry box as even sitting on the printer will ruin a roll of it if you live somewhere with more than like 20% humidity outside, also make sure your dryer can reach 85c to dry out a spool of PA, even with a dry box I usually dry PA immediately before printing it. As others have mentioned, definitely consider ASA or PETG or maybe even PC (if that printer can print it) where you don’t really need the material properties of PA specifically.
The tent will also probably be important for maintaining temperature of the chamber more than the smell, nylon doesn’t have a ton of odor anyway. You may need to put a blanket on it, you probably won’t need a chamber heater since nylon needs like a 65c bed or more, just make sure to pre-heat the chamber first by turning the bed on, I usually let mine warm for 20 min or more. It is alap important to keep the temps stable as nylon also warps easily which can cause it to pop off the bed while printing too So make sure the tent is sealed and try not to open it.
Sounds like an interesting project though, best of luck!
HumanPenguin@feddit.uk 3 months ago
Thanks very useful. More or less what I expected but great to get confirmation. Humidity here is 30 to 60% averaging the higher end more often. So def need decent drying chamber.
Yep, I knew the tent was more about retaining the heat. Just considered the hose a useful add-on. It is good to know you think that will be adequate as I could not find much online.
Do you think mixing colours at diff layers will be an issue as long as I keep both rolls in drying chambers?
Again, thanks for taking the time. It is fantastic to get some confirmations and advice from someone who has used the stuff before I spend what little cash I have.
bigredgiraffe@lemmy.world 3 months ago
Glad to help! Mixing colors shouldn’t be an issue, I have done it in the past, also have mixed PA and PA-CF in the past without issue. I bet you could even find a tent with a window and run a PTFE tube to a dry box outside the tent then you could pull the first color out and put the second one in without having to open the tent.
Also, just to say it out loud I would definitely test the strength of the layer adhesion (especially between the colors since they might have different additives) for anything structural, especially if you might get injured if it fails, just to be double safe heh.
Last, at least where I am, PA is significantly more expensive than ASA or PETG so might be worth looking at those for at least prototypes of the parts. For example, I typically use PLA to prototype ASA parts, has usually been fine to swap it out with just minor tolerance adjustments and it’s way cheaper to print 50 versions in PLA while I’m working out the design and then I print the final ones in ASA or whatever.