In 3D printing, success doesn’t end when a build finishes. Post-processing is critical to achieve the best possible part performance. Without proper cleaning, even a perfectly printed part can fail to meet expectations, dimensional accuracy targets, and surface finish requirements.

Across every industry, consistent and automated cleaning is what separates “fine” from “great” parts.

Why Automated Cleaning Matters

Historically, P3/DLP part cleaning requires manual or semi-manual processes. These solutions include:

1. Manual cleaning with brushes
2. Ultrasonic tanks
3. Single-tank solutions

Unfortunately, these methods introduce variability into the process. Differences in operator technique, solvent dwell time, solvent saturation levels, and temperature conditions all impact final part quality.

Of these variables, excessive solvent exposure is the most common cause of part deformation and long-term performance issues. Controlled systems prevent both under-cleaning, which leaves residue behind, and over-cleaning, which damages material structure.

Let’s Review Example A:

Bob puts a part into his ultrasonic tank and sets a timer for 5 minutes. While the part is cleaning, Doug calls Bob and asks him a few questions. Bob gets distracted. Bob comes back to the ultrasonic tank after 40 minutes. Although the 5-minute timer has stopped, his parts are still in the solvent. They have been overexposed, and the part is now warped.

This was an extreme example. However, when cleaning is a manual or semi-manual process, mistakes are inevitable (even with the perfect employee).

It is essential to have an automated solution that removes parts from solvent once cleaning is complete, eliminating the risk of overexposure. Consistent, validated cleaning workflows are crucial to achieving material performance. A fully automated system – that removes parts from solvent – is the only way to ensure success.

Why Your Solvent Choice Matters

Material manufacturers validate and publish mechanical specifications based on tightly controlled post-processing conditions. When cleaning processes vary from those validated workflows, part properties are negatively impacted.

There are various “standard” solvents validated by manufacturers — the most common of which is isopropyl alcohol (IPA). There are three key benefits to using IPA for part cleaning:

1. It’s affordable. You can purchase IPA for under $15/gal, while proprietary solvents often cost over $100/gal. When filling a cleaning system, IPA saves you nearly $2,500.
2. It’s reclaimable. IPA can be reclaimed and reused with a low-cost distilling unit, unlike proprietary solvents which require expensive hazardous waste disposal.
3. It’s validated. IPA is an industry standard solvent, with validated processes. Validation plays a key role in part success, confirming that exposure to the solvent does not compromise the material’s mechanical properties or overall functionality. If your material isn’t compatible with IPA, no worries. If you invest in an open-source system, you’re free to use any solvent.

Why A Dual Tank System Matters

All cleaning follows a two-step process: an initial rinse, followed by a final cleaning. All single tank systems require the second stage to be completed manually which reintroduces variability into the workflow. As a result, even single tank systems that appear automated still rely on manual intervention, limiting process consistency.

An automated dual tank system will place the parts in the first tank and then transfer them to the second tank for the final rinse at the correct interval. When cleaning has finished, the system will lift the cleaned parts out of the tank to dry. Dual tanks ensure proper and complete part cleaning.

The Onulis CleanPoint

The Onulis CleanPoint is an open-source, dual tank system, designed to remove operator variability by providing automated, repeatable cleaning.

CleanPoint ensures consistent solvent exposure, controlled fluid motion, and repeatable agitation patterns. The system is fast — with an average validated cleaning time of four minutes. When cleaning is complete, the part is automatically removed from the solvent. These factors eliminate the risk of part damage and improve cleaning effectiveness. Users can utilize pre-programmed settings for all validated Origin materials or do a custom program. This process has been validated by both major material manufacturers and third-party labs.

So, how does it work? Check out the video below.