PLA-F Blends PLA And ABS

In the early days of 3D printing, most people used ABS plastic. It is durable and sticks well to simple surfaces. However, it smells and emits fumes that may be dangerous. It also tends to warp as it cools which causes problems when printing. PLA smells nicer and since it is made from corn is supposed to be less noxious. However, PLA isn’t as temperature resistant and while it will stick better to beds without heat, it also requires more airflow to set the plastic as it prints. [Kerry Stevenson] recently reviewed PLA-F which is a blend of the two plastics. Is it the best of both worlds? Or the worst?

[Kerry]  did several tests with interesting results. He did a temperature test tower and found the material printed well between 190 and 240 °C. He did note some stringing problems, though.

The material had no real issues printing gaps and did not readily warp. What was especially odd, though, was that [Kerry] noted no smell from the material at all. You’d think it would either smell like PLA or ABS or some blend of the two. Another surprise was that the PLA-F appeared to be even less heat tolerant than ordinary PLA.

Given the results, we aren’t sure why we’d pick this over regular PLA. The tests indicate it may be even less prone to warping than PLA, but that’s not usually a problem. On the other hand, we didn’t see any real reason not to use it as long as you don’t need high temperature resistance.

Honestly, we really like PETG these days. Naturally, there are plenty of alternatives.

Thanks [ptkwilliams] for the tip.

31 thoughts on “PLA-F Blends PLA And ABS

    1. PETG vis very stringy and many brands need heat close to the temp the PTFE tubing in hotends degrades at.
      I have printed pounds and pounds of ABS and it only takes a few tricks to get good prints. ASA is even better than ABS but needs higher temps requiring an all metal hotend.

  1. I’ve been printing for some years but never used PLA except for a one little spool which came with my first printer. I’ve never understood why someone even bother with PLA when you have PETG.

  2. The problem I am having with all this is that ABS, PLA etc. are all not REALLY recycleable. By “real” I mean: Actually. Really. Not in-the-lab, but in reality without all the hurdles some countries are facing with reycling plastics (some are having a much harder time with this than others).

    There are approaches that SOUND like better ideas, be it PDK – last year’s pig-of-the-week – or be it PBTL, this year’s latest “solution to all the plastic waste”. 3d-printing (especially at home with all the waste one is producing) should try hardest to be economy-friendly. It’s bad enough to have to use all the packaging crap we deal with every day and not having a proper recycling system up and running, in place and ACTUALLY WORKING.

    1. As long as the plastics end up burned and not in land fills or oceans, recyclability of home 3d prints is not *that* important. Like you say, packaging plastic is much more common and many countries are still struggling to recycle even that in an economically viable way. Another big thing is recycling of clothes (after they are too worn for second hand market).

      Real impact of recycling is all about volume of waste. Recycling home 3D prints can give a nice feeling, but doesn’t matter in the grand scheme of things.

      1. “As long as the plastics end up burned and not in land fills or oceans, recyclability of home 3d prints is not *that* important. ”

        Why would burning PLA be better than placing it in a landfill?

        Raw PLA is non-toxic so does it leach anything into the water supply? Of course filaments have different additives but if they are a concern then the additives could be regulated.

        How long does PLA last in a landfill? I know there was some hype about PLA being compostable. When I looked into that however it is only actually compostable at high temperatures. Here in the US safety laws require landfills to be designed to maintain lower temperatures than where PLA composts. I assume other countries have similar laws. I’m guessing it eventually rots away at the lower temperatures but much slower. But is that a bad thing if the PLA remains in the landfill a long time?

        PLA locks up carbon which the corn it was made from removed from the air. I would think this is a good thing. The longer the better! Eventually it will be released back into the atmosphere once the PLA has been broken down but burning it would just do the same much faster. Also, if there is any incomplete combustion burning it could produce worse chemicals.

        OTOH, if the microorganisms in the landfill broke the PLA down into methane rather than CO2 that would be bad. Is that what happens?

        Don’t get me wrong. I’m not saying that printing and tossing a billion PLA benchies today is going to save the planet. I’m sure all the CO2 produced caring for the corn, processing it, converting it to PLA, transporting materials from place to place and even running your 3d printer is greater than what gets locked up in PLA. But if you are going to print stuff anyway why not leave that carbon locked up in the bottom of a landfill for decades or even centuries? And who knows. maybe one day we will have enough of our energy produced by carbon-free means that printing PLA could actually become CO2 negative.

        Anyway, I focused on PLA because being non-toxic modified corn starch I figured it would be least likely to pollute the water table. I actually don’t like PLA much due to it’s low glass transition point. I like plastics that can stand up to being left inside a hot car! Other plastics, made from petroleum don’t have the advantage of being renewable or being made from carbon that has been recently removed from the air but might any of those not leach bad things into the water in the bottom of a landfill? If you are already using the petroleum anyway is it really better to burn those than to bury them?

  3. I’ve only ever used PLA and I’m honestly bewildered why anyone uses anything different unless they specifically need flexible or high-temp or so on. As a general plastic, it’s great. It doesn’t tend to warp, it is strong with the grain and it is even decently strong layer-to-layer. It’s easy to print: doesn’t need a heated bed or high-temp all-metal hot end. It isn’t very brittle so long as you get one with a little additive to it (I use easyfil brand “impact-modified PLA”). And it doesn’t smell bad. And it is amenable to a ‘bowden extruder’ (extruder with a PTFE tube between it and the hot end), unlike some of the more exotic flexible filaments.

    I did use a clear budget PLA that had been stored in a humid environment, and it was super brittle. And I also have some PolyMax PLA that has a little trouble with warping and bed adhesion, and is so strong that it’s hard to trim surface defects off of. I didn’t care for either of those extremes.

    I think people who have a low opinion of PLA haven’t used it?

    I’ve never used ABS but I’ve heard numerous second-hand reports of its bad smell and extensive warping. I’ve been given an ABS part and it was warped.

    I’ve also never used PETG but from watching videos of how it breaks I’m just not convinced it’s much of an advantage over PLA. For example, the difference in its properties from with-the-grain and against-the-grain is really severe.

    Hey but I’d appreciate if anyone can recommend a long-lasting brand of USA-made PLA filament! I’ve been brand-loyal to EasyFil for 6 years now, no regrets, but each time it is a struggle to find a domestic seller and I’m still dubious about international shipping from Europe. I honestly don’t know if EasyFil is special or not, because I haven’t tried anything else once I found it, but it seems someone must make a decent middle-of-the-road non-brittle PLA here…

    1. I default to PLA for everything, but its low heat tolerance is its one major weak point. Last week I painted a part and left it on my back deck to dry, only to find that it had warped sitting in the sun in 80F weather for a few hours.

      If you need decent printing and your parts will ever have the chance to be anywhere other than a climate-controlled room, then you should probably use PETG.

      1. Huh, I guess prolonged direct sun must be a special challenge for PLA.

        The inside of my house regularly gets into the upper 80s and I don’t have problems with my PLA sagging. I also have a bunch of different bits of PLA on my bike, which I use for a few hours at a time in all weather…but I always park it in a garage. I even have a piece of extremely low-quality PLA that I use to screen the drain of my sink disposal, it even sees boiling water on occasion and it has degraded quite a bit but it has lasted 6 years. But I don’t put anything in a car, which would probably be about the most common challenge for a lot of other people.

        But I will keep that in mind if I ever do have problems with PLA outdoors..

        1. Have you looked at what MatterHackers makes?

          There are high temp PLA filaments that can withstand boiling water temperatures and can be washed in the top rack of a dishwasher.

          The top VS bottom rack is due to the heating element in the bottom of most dishwashers. If you don’t use a heated dry cycle, plastics should be fine in the bottom rack.

    2. I think part of it comes from non-impact-modified PLA combined with insufficient humidity control. PLA does do an excellent job for nearly anything for which you don’t need temperature resistance or other specialty characteristics.

      That said, ABS has the benefit of temperature resistance as well as the ability to acetone vapor polish it. I’ve also found that cyanoacrylate glue seems to bond to it better.

      ASA has the temperature resistance of ABS with the added benefit of better UV resistance and very smooth flowing. Best of nearly all worlds except that, like ABS, it shrinks as it cools.

      PETG is excellent for inter-layer bonding at reasonably high temperatures. Flexibility of it can be a huge plus for warm places where you’d rather have a part deform than break. Stringiness is a huge minus.

      Polycarbonate is great if you want even more temperature resistance and some semblance of flame resistance.

      …and the list goes on. One size definitely does not fit all. I keep a variety of filaments around for different functional and aesthetic characteristics and choose which one I use based on the application. Is it going to spend its entire life indoors in a climate-controlled office and needs to look nice? PLA. Is it ever going to sit in a hot car? Well, can’t use PLA. Maybe HT-PLA, but that depends on the environment. Will it spend time in direct sunlight? Don’t use ABS. Is it going to be in nearly direct contact with a heating element? Polycarbonate, PEI, or possibly flame-retardant ABS are certainly going to be better choices than PLA.

      So I don’t begrudge anyone for using different filaments. They all have their place. It may just be that your applications for 3D printing are different than mine. If PLA works for everything you need it for, then great! But most of my printing is for functional parts, and the difference in filaments makes a huge difference for me.

    3. “I’ve only ever used PLA and I’m honestly bewildered why anyone uses anything different ”

      Can’t leave it in a hot car.
      Can’t leave it in a hot attic or a non climate controlled storage place.
      On really hot days can’t even leave it outside! – yes, I’ve had PLA prints deform that way. I tried to print some boating accessories from PLA.

      This might be fine for knickknacks in an air conditioned house. I like to print parts for machines which I might leave in my car during a work day to take to the makerspace afterward. Or they might be parts of bigger projects that I put more effort into building or even designing so I want to keep longer term. At some point that might mean storage.

      Many prints might never actually need to handle higher temperatures but I prefer not to have to make this determination at print time. Once the print is finished I’m unlikely to ever regret the fact I used a better plastic but I certainly might regret having made it from PLA.

      Also, have you ever solvent-welded ABS? Having that ability is nice!

  4. I once did a print with PLA then afterward decided to use Nylon for smething else without cooling off the extruder barrel.
    When I quided the nylon into the barrel with a little force, a blend of the two came out of the nozzle which made me wonder if anyone’s tried a making a a hybrid filament of nylon/pla with the lower PLA temp and the higher strength of nylon?
    Alas, I lack the equipment to melt , blend and extrude my own filament
    As a gardener I make a lot of fixtures to hold irrgation emitters and float valves and such. PLA will warp and/or turn to powder in the hot sun but PETG with some Smoothe-On lasts and lasts.’
    For doo-dads and fixtures for use inside PLA works fine.

  5. I have printed quite a bit with the pla-f blend. It penny’s quite nice and makes great functional prints. I have a problem with the methodology used for the heat tolerance test in the original article. It was already described as having more flex than pla, if you take the thinnest legs you can print and put a load on top in the heat of course the more flexible one is going to collapse first.

    I think a better test would have been to make some hooks with walls and perimeters similar to cnc kitchens videos and test them under load in the heat.

    I have used this to make tools (push sticks, handles, organizers) in my shop that without question are better than the pla only printed counterparts of the same tools.

    Also, the way the layers bond together with the pla-f make it particularly good for lithophanes. Many people have a hard time getting horizontal lines to completely disappear in their lithophanes and they just completely disappear with the pla-f.

  6. “Another surprise was that the PLA-F appeared to be even less heat tolerant than ordinary PLA.”
    That was to be expected. Blends usually have a melting point below the melting points of their components, just like solder alloys or salt on an icy road.

  7. I made a bracket to mount an old Terk TV antenna to a vertical pipe. The plastic clamps that held the antenna loop to the DirecTV dish were cracked and since I was getting rid of the satellite dish I needed a different way to mount the OTA antenna.

    I straightened out the curve in the antenna loop then designed a 3 piece bracket to clamp the two uprights of the antenna loop and the pipe into a sandwich with bolts through it.

    Material is fluorescent green Excelvan PLA. It’s been up in the sun and weather for over 2 years. I was on the roof not too long ago, the color has faded but no sign of the plastic going to pieces.

  8. PLA is more rigid than PETG, which can be desirable. While that makes it more brittle, it is somehow surprisingly more impact resistant. As a result it’s often a better choice for functional parts that don’t get exposed to heat, such as furniture parts, fixtures, jigs, tool patterns, … (Pro-tip: don’t use black PLA for functional parts that may occasionally get exposed to the sun, even if just through a window …)

  9. I don’t know if the PLA-F you’re reviewing is the same one that I bought (one giveaway is the beautifully wound spool – it’s Prusament-like in regularity) but the reason I love it is because it effortlessly lays down a very nice first layer. It’s one of those “modified PLAs” (usually referred to as “PLA+”, like eSun’s), some people seem to think it’s got TPU mixed in with it (rather than ABS). Like other modified PLAs, it’s more flexible than regular PLA, which also means it doesn’t sand or file as easily. I print it at 220 degrees C.

    One of the local 3D printer vendors sells it for about USD13 a kg. Problem is he’s out of white and black at the moment. You can find it on AliExpress but it costs more.

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