As a soon to be first time 3D printer owner, what filaments would you recommend I get? (Mfg as well as material types.)
There are so many manufactures out there, and such a wide selection of materials, it can be a bit overwhelming. It’s easy enough to look for top manufactures, but I wanted to see what this communities recommendations were.
PLA is a given, but I’m also considering getting some PETG for more mechanical parts.
You know what they say opinions are like … Everybody has one! The old adage you get what you pay for is true, but then there are some filaments that will surprise you. Personally I think it’s more of how well you have your printer dialed in then the filament itself in most cases. Where you live, I would suggest having a filament dryer and or making sure you store your filaments with silicate gel and well sealed when not being used. Welcome to the world of 3D printing!
I’m getting a Geeetech A10 like @HalfNormal recently acquired.
I will definitely have dry boxes to store my filament, humidity is bad here on the NC coast. Been hanging around you 3D printing peeps long enough to have picked up on a few things.
I also know enough to know that my big learning curve is going to be learning how to dial in the settings for my printer.
The decision to finally getting a 3D printer was made easy because I knew that I would have support of all the great makers here in this community. People that will be happy to answer all my newbie questions without being condescending, like you see sometimes see in other groups (coughfacebookcough) .
We don’t get a lot newbie questions here (at least that I notice), so I plan to ask lots of questions to hopefully draw other people in with conversations. I created this Discussion sub cat because there didn’t seem to be a obvious natural place to have these discussion other the under the general parent cat, which I don’t like. I’m open to change this if anyone thinks there is something better.
I started with PLA as typically the easiest to print, and I printed in PLA for years. I still use it for a variety of purposes. It feels different than other plastics. I haven’t needed to print math shapes for my wife to use when teaching math this year, since that’s been virtual, but I do expect to get back to that once vaccination is general and life returns to something like normal.
My default is now PETG because it is the most dimensionally true; that is, it shrinks least after printing, so when I want to print things to fit (like parts for #monocle) it’s a good choice. It is the most accessible tough filament. If your printer comes with a glass bed you want to be careful; PETG will rip up chunks of glass because it sticks to glass so well. It also tends to curl up around the nozzle and foul parts with globs of burnt plastic, so I end up cleaning the nozzle before every print.
ABS, even low-odor ABS, stinks and my family forbade me to print any more until I got an enclosure with active carbon filtration in place.
It seems this topic was split, but the link is broken, so I’ll comment here.
I use PLA for almost everything, except for stuff I’ve printed to use in my car, which can get hot in the summer. I had printed a cell phone holder that fits into my cupholder using PLA and it warped in the summer heat. Printed the same thing in PETG and it survived a hot day with the windows closed. I’ve found PETG to be mechanically tough–similar to ABS–but much easier to print. I usually print on blue tape and both work fine–no waiting for the bed to heat up.
It’s possible to use PLA for things that need to get hot, but you have to crystallize it. I’ve heard of remelted PLA slow-cooled being used for handles on tea kettles. I had been hoping to experiment with packed fine salt (like popcorn salt) but someone beat me to it and reported success. Hackaday featured that recently:
The point is that you have to hold its shape while melting it and then letting it cool very slowly, causing it to crystallize. “Annealing” is usually used metallurgically for processes that toughen by reducing crystalline features as well as remove internal stresses, but this heat treatment for PLA makes it more brittle, not more tough.
PLA gets a bad rap as the cheap plastic for new folks, but I’ve found nothing that matches its pleasant feel to the hand. In February, I printed what I expected to be a prototype speed vice handle for my mill in PLA. I did a few experiments before landing on my current design that supports the printed handle shoulder bolt with a small M4 bolt inside it. I printed two copies and figured they would together last me a few weeks of trial, during which I would mill a replacement out of aluminum, but the second iteration is still sitting in a drawer unused. I rarely pull out the full handle. The middle twelve-point socket I thought would be weak is strong enough that it’s almost always all I need to use to lock parts in place, and even though I lean into it pretty strongly it’s still showing no real signs of wear ten months later. I did put the outer part of the handle on the lathe to smooth it out, but a file/sandpaper would have been fine, using the lathe was just gratuitous use of a lathe because of course you use a lathe if you have a lathe, they are magic machines… The PLA just feels nice to the hand.
I remember when we bought our piano that they said that the plastic on the keys included cellulose, and was designed to absorb some moisture to give it the feel that pianists have liked on ivory, back when piano keys were made of ivory. PLA has some of that feel too.
I say all that in praise of PLA even though I almost always print PETG these days. I’m mostly printing mechanical parts that require dimensional stability and toughness, and expect to print more PLA again some day.
I store my opened filament in sealed storage bins:
I print out of a similar but smaller sealed bin with a hole for the filament.
In both the storage and printing dry boxes, I use non-cobalt indicating silica gel:
I keep track of humidity in the storage and printing dry boxes with cheap hygrometers:
I use a spreadsheet to track total weight including before an after drying, so I know what is left. I assume that a 1kg spool has at least 1kg of filament on it so guess the empty spool weight as gross weight minus 1kg on first dry weighing before use. I weigh the filament before putting it on the printer (and check for weight to have increased from adsorbing water) and when I remove it from the printer.
Since you aren’t starting with an old printer, you won’t have an extra old printer bed around to make a drying oven with like I did. A neighbor is happy with his PrintDry; others claim it doesn’t get hot enough for drying some filaments.
If you keep PLA sealed in one kind of dry box or another with silica gel, even while printing, you can probably get along just fine without a dryer; I did for quite a while. However, I have gotten PETG that I get 3g of water out of immediately after removing it from its vacuum pack. I wouldn’t recommend PETG without a drying oven. PETG is terrible to use when wet.
If you want to make parts that are a little bit tougher than standard PLA, without getting into PETG yet, try PLA+ / PLAPro. They print at slightly higher temperate and have some modifiers in them to make them less brittle and tougher. I’ve made functional parts with PLA+/PLAPro multiple times.
If your PLA filament breaks, it is probably wet and needs to be dried. PLA becomes more brittle as it adsorbs water. It also prints worse.
If you have a kitchen oven with a “warm” setting of about 150°F that’s about right for drying filament.
Hmm, I own a large food dehydrator that can fit at least a couple of spools no problem. Looks like a PrintDry is basically a food dehydrator with a custom top. My dehydrator is box shaped with removable tray screens so no custom accessories needed. It goes from 105 - 165F (41 - 74C). So it appears I already own a filament drier.
I’m also getting some cheap hygrometers and they all claim like ±3%RH accuracy. To check the accuracy of a hygrometer you can use saturated aqueous solutions of different salts. The following linked pdf is a monograph put out by the National Bureau of Standards back in 1976 https://nvlpubs.nist.gov/nistpubs/jres/81A/jresv81An1p89_A1b.pdf.
It gives the %RH for for different saturated solutions for different salts at different temperatures (Table 2). I’ve used these solutions setups many times in my lab career for getting different RH environments.
You need an airtight chamber, usually a jar with a screw cap will work, a particular salt, water and a stand for the hygrometer to sit on. The water needs to be saturated with a full bed of excess salt remaining in the bottom and with a thin layer, ~2mm, of water on top. You also need to know the temp accurately and preferably fix the temp of the setup to one of the indicated temps. But you can extrapolate to other temps if needed. Usually let the setup equilibrate at least 8 hours before reading for the best accuracy.
Some of the salts shown may not be easily obtained but, since the accuracy of the low end is most desirable to know, salts like: sodium hydroxide, potassium hydroxide, potassium acetate, and potassium carbonate are easy to obtain. They preferably need to be of a decent purity .
Honestly, I think that the exact humidity doesn’t matter. Using indicating silica beads is enough to be dry enough as long as you cook them before all the indicating beads are dark green; the hygrometers are just because they can be easier to see looking through the side of the bin than a few indicator beads. The hygrometer is just to notice the delta if humidity goes up; accuracy doesn’t matter as much as sensitivity, I think.
I agree with you that, for this application, the accuracy isn’t really critical if you are using color indicating desiccant. But if you ever wanted to know the accuracy of your hydrometer there is a relatively simple setup to do so.
If you haven’t decided yet on anything in particular, I’ve had years of good luck with aquanet extra hold hair spray. A little goes a long way, and it can be the difference between failures and success with both PLA and PETG.