The Workhorse typically needs a slightly hotter print temp … the best way to find the ideal print temp for any filament is to print a “temperature tower” (sometimes called “temperature ladder”).
You can find a post on that here: Temperature ladder
The part used (there are many you could find online – e.g. just visit a site like thangs.com and search for “temperature tower”) prints a series of repeating sections (think of these like the floors in a high-rise building). But each “floor” is printed at a different temperature. When completed, you inspect the part to determine which section has the best quality – visually and also for things like strength.
The post has instructions w.r.t. how to use the extension in Cura – this will trigger the temperature to change automatically at specific layer numbers – you wont need to fiddle with the temperature during the print.
When I print PLA … I usually find that temps closer to 230°C work best. But this can change due to things like filament brand or … even filament color. White (titanium dioxide) is often problematic in many filaments. When you select a filament … such as PLA, PETG, TPU, etc. the business part of the filament is basically clear – but there are additives. These create color and other properties. These additives change the properties. For example “silk” PLA (which has a nice shimmer) tends to be weaker layer-adhesion and the filament itself is more brittle than normal PLA.
Basically it isn’t safe to assume that one PLA will print just like another PLA – but they are often close. To be sure … run some tests such as the temperature tower.
As for bed adhesion… the Workhorse comes with a reversable bed … it’s PEI (with a matte finish surface) on one side … and glass on the other. Flip the bed as needed. (You can also order the flexible magnetic bed for it.)
PEI will eventually wear out and need to be replaced – that’s normal and not a defect. PEI has a “matte” side and a “glossy” side. When you replace the PEI you can get it from places that offer a choice as to which side has the adhesive.
As for warping and the part coming loose off the print-bed…
One property of any substance is the coefficient of thermal expansion… how much does it expand or contract when heated and cooled. ABS has a higher coefficient … PLA has a lower coefficient. This makes ABS a more difficult filament to print.
The bed will maintain the 1st layer at the bed temperature. But as the layers go up and up … the “hot” filament comes out and then “cools” … and contracts as it cools. But this means those upper layers can contract MORE than the lower layers. The difference in tension from bottom to top … with the top having more tension … means the part can warp and start to peel off the bed.
ABS is one of the problematic materials … it isn’t advised as a “beginner friendly” filament.
PLA has a low coefficient of thermal expansion … so it doesn’t contract very much as it cools and the parts are usually stable. This means it is a “beginner friendly” filament.
But even with PLA being an easier-to-use filament … there can be reasons why it isn’t sticking well to the bed.
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Make sure the bed is clean. Use isopropyl alcohol to make sure there are no skin oils, etc. that might weaken the adhesion. Rather well-worn PEI can sometimes be helped by polishing with fine-grit sandpaper.
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Sometimes PEI alone isn’t enough and you may need something more. One of the most common adhesives used is PVA gluestick (Elmer’s Glue is PVA). This is a water-soluble glue. It improves the adhesion – especially when hot – and is easily cleaned off when finished because it is water soluble.
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Printing some filaments such as PETG … tend to stick a little too-well and require an adhesive that doubles as a release agent. PETG is best printed on the “glass” side of the bed using PVA (Elmer’s Glue-Stick).
I use an adhesive & release agent called “Magigoo”. It bonds fairly well when hot, but once the bed is allowed to cool completely, parts release effortlessly – almost as if they weren’t stuck to the bed at all. If I’m being completely honest, I think it bonds just slightly weaker than PVA (when hot) … but it release MUCH easier when cold. When Magigoo isn’t working well enough for me … I switch to PVA. If I’m still having warping issues… I use my enclosure.
60° … or even 50° should be enough bed temp for PLA.
When printing PLA you would normally use the part-cooling fan on high (100%). When printing PETG you have a bit of a choice … no part cooling at all will give best layer adhesion and the part will have bit of a glossy look. But if you use a fan at all… it should be very low such as 5-10% only and that will give the part of a bit of a matte finish.
PLA is possibly the very easiest filament to print – strongly recommended for a beginner filament. It’s properties tend to be very rigid and somewhat inflexible when the part is completed – such that if you attempt to flex or twist a printed part you are likely to hear cracking sounds – the cooled filament is brittle and not as flexible as many others. PLA is non-toxic. Most filaments will absorb water from the air and this creates problems when printing (the moisture in the filament then tries to “boil” when coming out of the extruder putting bubbles in the filament and reducing the print quality. PLA does technically absorb moisture … but not nearly as much as most other filaments. One downside to PLA is that it softens at a lower temperature than most other filaments. In very hot environments, parts made from PLA may soften and fail (think … printing parts that would be used in a car interior on a very hot summer day).
ABS filament is a bit more flexible – less brittle. But it is difficult to print. It has a high coeffecient of thermal expansion and contraction and that means it tends to want to “warp” off the build plate. It really needs an enclosure (build chamber) around the printer for all but the smallest of parts. It is also toxic – it needs to be vented when printing (you wouldn’t want to be in the same room for extended periods of time.)
For a while your filament choices were mostly PLA vs. ABS. But there have been numerous advancements and now there are a crazy number of filament material choices.
PETG offers the flexible properties of ABS … but is non-toxic and easier to print. It’s coefficient of thermal expansion isn’t as low as PLA … but not nearly as high as ABS. So it’s slightly more difficult to print than PLA – but not much. PETG is a co-polymer that is generally used as a more friendly replacement to ABS. It’s easier to print and non-toxic but has similar properties w.r.t. flexibility.
PETG is a co-polymer that has become extremely popular and tends to be used for applications that would have required ABS. It’s not honest to say that PETG makes ABS obsolete … but it is fair to say that for many applications that would have required ABS … PETG can be used and it makes things a lot easier.