PreForm provides print time estimates as part of job preparation to help you improve scheduling jobs and manage workflows. Print times are calculated by evaluating various factors such as printer type, part geometry and volume, material type, layer thickness, and print settings. PreForm offers two types of print times: estimated print times and calculated print times.

Both estimated and calculated print times are intended to help you plan and optimize your workflow. They can still be inaccurate due to outside factors like printer issues.

Estimated print times are rough estimates provided each time your model is adjusted in PreForm. These print times are intended to estimate how long a job will take to print while you prepare the job. Different part layouts, orientations, and support settings affect print times. To help reduce print time, refer to Model orientation best practices for SLA printing.

Calculated print times are more precise than estimated print times. Because they are slower and more resource-intensive to determine than estimated print times, they must be manually initiated.

Initiate the calculated print time by clicking Time Estimate on the right hand side of PreForm. The calculated print time in PreForm is displayed as Print Time. The calculated print time is also visible on the printer’s touchscreen after the job upload is complete.

Both estimated and calculated print times are based on the amount of time it takes for the printer to complete all of the layers in a given job, but do not include the time it takes to prepare the printer for printing, also called preprint.

Preprint is a series of actions the printer takes to prepare for printing. These actions include preparing the resin tank, heating up the printer, checking the build platform for debris, and checking the printer’s optics system.

Depending on the previous state of the printer, these actions may take more or less time to be completed. For example, if a print has just finished and the resin tank was not changed, the next print can start with reduced heating and filling time. Formlabs recommends using the same resin tank for consecutive prints to help reduce or eliminate tank filling times.

Formlabs SLA printers can reduce preprint time by automatically starting the heating process.

Form 4 and Form 4L generation printers

The printer can automatically start heating the resin in the resin tank when you upload a print job. This reduces the total time required for the print. The printer displays Preheating in the top-right corner of the touchscreen when this is happening. You can turn off preheating by tapping Settings > General > Resin preheating.

Form 3 and Form 3L generation printers

If predictive preheating is enabled, the printer starts to heat up when you interact with it before starting a print.

To enable predictive preheating on the Form 3 or Form 3L:

1. Tap the wrench icon on the bottom left of the printer's Home screen. The Settings screen appears.
2. Tap System. The System screen appears.
3. Tap Predictive Preheating. The Predictive Preheating screen appears.
4. Tap Predictive Preheating to enable or disable predictive preheating.

For safety reasons, predictive preheating times out if a print job is not started. The timeout length can be selected by tapping Timeout in the Predictive Preheating screen. You can select a time period of 15, 30, 45 minutes, or an hour.