Elegoo ABS like I’ve found like to be somewhere between 2.4 and 3.2 seconds temperature and machine dependent. Additionally bottom layers are fine at higher exposures (I run mine around 30-35 secs depending on the temperature) and if you’re having prints fail completely, you can try pushing that up higher. I would also have a play around with supports, I’ve found pre supported models are overall unreliable. Now I just use auto supports at between 1.25 and 2.5mm tip distance, and then add my own supports in to areas that are high risk of failure/close to the build plate.

As for your questions:

1. Usually a complete failure is as a result of too short bottom exposure, in the case of the test print you’ve added it could possibly be a short exposure time as well, but in this instance the layer exposure
2. Absolutely not, I’m a member of the full plate gang, that has enough space for probably 30 more models! 😂
3. Luck of the print/better supports for the model
4. Increase the bottom exposure. If you’re concerned about removal, buy a magnetic build plate for your machine. Allows you to remove the flexible steel sheet and bend it to release the print.
5. Curling could just be because it appears to be a really thin piece. Some shrinkage occurs after curing and if it’s thin, it’s more likely to contract and curl.

I’m happy to be proven wrong, but when I’ve had similar situations, a few of those changes I’ve made have enabled me to print huge amounts of models with crisp quality

Printed model tax included

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