Hi, after printing about a year with PLA, I tried printing PETG and ABS. I thought it might be handy for other Vertex owners to share my experience. The reason I’m considering other material than PLA is that in the next months my printer will run many hours printing box-shaped objects 190100170mm. These will be filled with mineral oil and be in service for at least 10 years. So I need the most durable material I can print.
pla:
easiest material to work with, sticks to the bed (no need for heated bed), and allows the highest level of detail in prints.
whatever you read on the internet, PLA doesn’t dissolve in water! I have some PLA housings sitting outside in the rain and sun for about a year now, the material keeps its strength and shape. Maybe it got a bit lighter colour from exposure to the sun.
PLA is however hydroscopic, so in terms of water-tightness this might give problems over time.
print speed at 0.2mm layer height, 0.5mm track with; speed is limited to ~70mm/s, otherwise extruder starts to stuggle. It’s a pity no other hotends are available with other diameters for the vertex.
printable between 185-210°C depending on quality vs speed vs strength
printbed calibration at 0.2mm distance from the nozzle or a folded sheet of paper
mechanically very hard but brittle
PETG:
I chose this material because you can print it without heated bed, and it is a hydrofobic material, same material as soda bottles. Ideal for watertight objects or outdoor applications
less brittle than PLA, more flexible thus stronger. For example printing fins of ~1mm*10mm are much stronger than in PLA.
nice semi-transparent finish
almost as easy as printing PLA, maybe a bit less detail
print speed also limited as PLA, hotend temperature ~235-245°C
printbed calibration at 0.2mm distance from the nozzle or a folded sheet of paper
ABS:
most difficult to print, a heated bed requires some work. I installed MK3 bed, semiconductor switch and power from my lab supply
I installed spacers between the alu bed-frame from the vertex and the hotplate, I got it to 120°C at 30Vdc. Installing thermal insulation will be feasible.
the part I printed was a bit challenging~(base 25*75mm): it had overhangs at 35-40° starting from the base. With bed temperature at 100°C corners started pointing upwards by ~2mm when part thickness of about 2-3mm was reached (known as mouse-ears). there was a lot of touching between nozzle and part. Especially the second unused nozzle bumped the part a lot. However the part came trough with some imperfections at the base. But not ideal in terms of repetitiveness of the print. The adhesion to the bed was sufficient for the part not being bumped of the plate. However the corners had slight signs of curling
ABS has very good interlayer adhesion, vertical walls have the nicest finish of all tested materials
when melted ABS appears to be more liquid than PLA or PETG, so probably higher printspeed will be possible with the same nozzle diameter
to my first impressions I think ABS allows less detailed prints compared to PLA and PETG, but allows great finishing (google ABS acetone vapor finish)
ABS printing: heated bed vs cold glass plate with buildtak
Because it’s a lot of fuss installing a heated bed each time you want to print ABS, I also tried printing the same part from above directly on the standard Vertex Buildtak covered printbed.
To my pleasant surprise the buildtak outperformed the hell out of the heated printbed!! Strange but true the curling of the corners at early stage of the print was almost non-existant, there was no touching between nozzles and part. the part came out perfect
After removal of the finished part there were no signs of warping, all corners remained firmly to the printbed.
Very important is you get the the distance between nozzle and printbed correct. 0.1mm or a single sheet of paper is advised. Also set first layer height at 200-300% in slicer settings. I printed first layer at 245°, others at 235°C. All fans off.
I’m quite confident I can print large footprints 190*100mm in ABS, without any need for brims; if nozzle to printbed distance is set correctly. In fact if the printbed would not be removable, I would damage the printer trying to get the part off the plate. It adheres much better than on the heated bed. I say for now: to hell with heated printbeds!
Small update on the ABS printing. I attempted to print a large box-shaped object (190100h175) with 2mm walls and some internal fins.
The part sticked to the buildtak the first ~4 centimeters, however on further inspection the print started to show slight detachment from the printbed after ~7cm. Even worse there were some layers showing cracks between them (interlayer adhesion).
It seems that warping forces continue to build up when the part becomes higher.
After further inspection I saw some bubbles between glass plate and buildtak when looking from underneath. So the buildtak got torn off the glassplate, warping forces of the ABS must have been huge.
So even with heated bed I don’t think you can print large objects(with solid walls) in abs, simply because the heat from the bed can’t reach layers +5cm high. Even if you have a solution that keeps the part flat on the bed, I think the ABS will tear itself appart(interlayer). I googled and youtubed but I didn’t find a solution.
I’ll give it another shot using the abs-slurry technique and setting temperature a bit higher for better interlayer adhesion, but I think the best solution for large prints out of durable material will be PETG. The same box came out perfect on the unheated plate, no signs of interlayer weakness.
I’m printing big objects in ABS (like this one) on a regular basis without any warping issues. I’m using a heated bed coated with Dimafix. To avoid unsticking layers you need to print with enough infill (at least 50%). It’s best to have your printer in an enclosure but I still don’t have one (only a door).
For the vertical walls I have solid infill(, there are also some cracks there. Maybe I should print at higher temperature than 235°C?
I had a look at the train from your link, really nice! The part numbered ‘1’ is a bit similar to the one I’m trying to print. Do you print the vertical walls solid? However because of the windows your design is less susceptible to warping, these break up the tension.
Do you think you can print a hollowed out box with solid 2mm walls that large size? the slic3r software 1.2.9 has a bug that over-extrudes the walls (gap-fill issue), could that have anything to do with it?
Is a printer enclosure rather for having higher temperatures of the already printed layers, or for avoiding drafts(also heard that)?
edit: I just saw that my slicer settings only printed one diagonal direction per infill layer. Probably the grid-type infill which prints both diagonals per layer will be much stronger.
I’m using Cura. Over 25%, the infill is linear. 100% infill is a bit over-extruding so I’m using 50-60% instead. I’m also using 20% infill overlap. And I removed the small fan.
[quote=“TLS”]Do you think you can print a hollowed out box with solid 2mm walls that large size? [/quote]You can but it will always be a bit tricky. I’ve had some boxes being perfect at the end of the print and showing tiny cracks hours later (as you can easily glue ABS that’s not so big an issue but still). Letting the object cool down slowly is also an important parameter.
[quote=“TLS”]Is a printer enclosure rather for having higher temperatures of the already printed layers, or for avoiding drafts(also heard that)?[/quote]Both actually. But you can’t have too big temperatures inside the box or it will harm the stepper motors (60-70° max). I’ve read some people using a heat gun blowing on the print. Avoiding drafts is also very important.
I’m printing ABS between 210 ans 225° depending on the color. These low values are needed to compensate the inaccuracy of the sensor. With higher values, the nozzle tends to clog too easily.
I’ve tried using the heated bed again. The first 4cm are ok, then I saw slight detachment from the heatbed. The interlayer adhesion seems to have benefit from the heated bed.
Maybe if I can get the adhesion better (using ABS slurry or light sanding of the alu heatplate surface?) I can keep the object from warping.
Problem with these large object is that infact the heat is much needed at the ‘printing hight’, rather than just at the build platform. Would installing two spotlights just above the printer help?
Raby, Which version of Cura are you using, stand-alone or called from repetier? I just installed 2.1.2, you cannot select the Vertex printer, but Prusa comes close in terms of build volume. I haven’t figured out how to instruct the slicer which extruder to use in my double extruder setup. However I’m happy to see that the thin walls are better than in slic3r.
To keep the ABS prints sticking on the bed I’m using a 3D adhesive spray (Dimafix or 3DLac). It sticks like hell when the bed is hot and the object pops up easily when cold.
[quote=“TLS”]Would installing two spotlights just above the printer help?
[/quote]It certainly would. Avoid too much heating though.
[quote=“TLS”]Which version of Cura are you using[/quote]I’m still using the one embedded in Repieter. It fulfills my needs so I didn’t spend time on trying another one.
I’m regularly printing very thin objects like the handle bars on my train stuff (1mm in diameter) and they come out perfect.
a few attempts further to print my big object in ABS… Challenges are detachment of the ABS from the build platform and cracs in the walls of the object due to surface tension.
Both of these issues could be remedied:
use of ABS ‘juice’ or ABS ‘glue’: first time I was using a too low concentration of ABS in the juice and the object detached. Second time I used too high concentration of ABS (more ABS glue) and object was sticking too much to the build platform, I had to chop it off and damaged the object while doing so. SO I guess there is an optimum solution between that, so it can work
use of 150W spotlight to keep top layer hot: while doing so the print level material stayed around 60-70°C. Needless to say this used a lot of energy during 25-30hr prints, and you risk burning down your house because printer is running really hot
One other problem that came up was interlayer cracking due to a single non-perfect layer caused by temporary reduced flow of the nozzle(blockage). So I still got a crack that rendered my object useless…
As far as I am concerned, ABS is a ‘pain in the ass’ to use for large prints on the Vertex. I love a challenge but I think PETG is the way to go for large objects.
Raby, If you think you would be able to print such object, and would like to give it a try; I would be happy to send you the STL and compensate you for the ABS (~120m! per print) used.
Although I have never done ABS on my Vertex I have regularly done it on my XYZ printer. The XYZ is fully enclosed and has a heated bed, but still large boxes shows cracks in the upper layers. The way I solved this was relatively easy: I put in an old toaster (!) where I had modified the electronics with an Arduino and a solid-state relay to allow for PWM controlling the power. Currently it is set to around 80W, which gives a nice 55 deg C interior temperature and this is enough to prevent cracks in large boxes as well as reduce the warping and associated pull on the build surface.
The Vertex is quite easy to enclose; I think I put up some pictures of my “enclosure” using some thick soft plastic (identical to typical raincovers for strollers, etc). Just take care to monitor the temperature; I have no problems up to 60 deg C though…