Means the part will not be where the printer thinks it is and will apply the filament in the wrong place.

How thin does an ABS print need to be and how fast does the print bed need to move for that to happen though? I know you agree that this is likely not an issue too, I'm just curious. It's hard for me to imagine that happening.

Granted, If I want a perfect print I slow my infill speeds because you have to print pretty hot for those speeds, which has numerous downsides (poor bridging being the main thing).

High gap fill speeds also cause severe  vibration without significant consequences.

TickTock wrote:

Vibrations much smaller than I can see...will result in unacceptable print quality.

Just out of curiosity, why?
Forgive my lack of basic knowledge on this.

Means the part will not be where the printer thinks it is and will apply the filament in the wrong place.  Consider an exaggerated scenario where you are putting down a line on the Y axis.  If the part is tall and has mass, it will tend to continue to move even though the bed has stopped and you will overshoot the end before bouncing back.  I guess this would manifest as little bumps near the top at the corners of a tall, square model.  If I had access to a Prusa, it would be fun to make a diabolic model to illustrate this - a square hourglass or something like that.

Vibrations much smaller than I can see...will result in unacceptable print quality.

Just out of curiosity, why?
Forgive my lack of basic knowledge on this.

TickTock wrote:

I cannot imagine there *not* being vibrations at the top of a tall print impacting quality for a moving bed topology.

if you want to test this, just print a very thin and tall model on your glass bed and then shake the glass with your hand. Does it bend or pop off? if not, then there you go.

I don't think it's that simple.  Vibrations much smaller than I can see (and certainly much smaller than that required to detach the model) will result in unacceptable print quality.  That said, I acknowledge that it can't be that bad since so many are having good success with this topology.

DePartedPrinter wrote:

I would go SLA instead of FDM.  Out of your budget range but I would pick up a Form 1.  I got the chance to play around with one and they are very impressive. The detail you can create will blow your mind...

If the resin prices drop one day and build areas increase SLA will become more popular, until then I don't see it as a practical alternative for many users.

I think most people just want to go on thingiverse, find some object, click print and expect this perfect representation to be created. FDM doesn't come close to a perfect representation.

I think peoples expectations for FDM are way to high and I think people would be happier with SLA over FDM because of this.

I cannot imagine there *not* being vibrations at the top of a tall print impacting quality for a moving bed topology.

if you want to test this, just print a very thin and tall model on your glass bed and then shake the glass with your hand. Does it bend or pop off? if not, then there you go.

Hehe. It seems like it at first, and seems very counter-intuitive, but once you think about it it's actually not the case and is easier to set up (the moving bed, not bread ).

If the resin prices drop one day and build areas increase SLA will become more popular, until then I don't see it as a practical alternative for many users even if the cost of the printer itself is lowered.

FDM tech just has limitations that will always have users seeking more.

I don't really get what the issue is there. Does it change how well the butter is applied to the bread if you apply butter on your bread by moving the knife on the bread, or moving the bread on the knife instead?

I think the main issue is actually that the bread is a heck of a lot heavier than the knife :-). You can butter faster by moving the knife.

jagowilson wrote:

People who have lost glass over a print that stuck too well know exactly what I mean.

Yeah, that's happened to me. Was rather surprised, as I had lifting on the edges of the print too at the same time as the middle being "superglued" in place (15cm wide print).

Same here.  I've thrown away two glass plates so far due to too many chips of glass missing from both sides (I use one until is becomes unuseable, flip it over and continue using until that side has too many chips, then toss it).  I've found I actually have better luck removing the part *while the bed is hot* - contrary to popular knowledge that letting it cool and pop off on its own is best.  Alcohol is helpful removing the glass chip from the part - doesn't seem to affect ABS but does dissolve hairspray.

Back on topic.  I do not know from experience but at high print speeds, I cannot imagine there *not* being vibrations at the top of a tall print impacting quality for a moving bed topology.  Do you just slow down on perimeters so the total print time is not impacted much or does the vibration I am imagining really not exist at speed (>60mm/s)?  For simple, less intricate, things with smooth features like vases I don't imagine it would be a problem either.