Process Overview
All manufacturing processes involve following a series of steps to create final parts, and Digital Light Synthesis™ follows the same approach.
View the following video for a summary of the process of producing parts with Carbon's DLS technology.
1. Print Prep
- Use a computer to access the printer UI.
- Orient, support and arrange digital models.
2. Resin Dispensing
- Mix resin and fill printer cassette with the amount required for printing.
3. Printing
- The automated process where the printer creates parts by using UV light to solidify the liquid resin.
4. Part Removal
- Printed parts need to be removed from the platform either before or after washing.
5. Washing
- Liquid resin is removed from parts by rinsing with solvent or by spinning.
6. Curing (Baking)
- Parts achieve their final mechanical properties through the application of UV light (one-part resins) or heat (two-part resins).
Always reference resin-specific page and protocols for detailed information of each step. Information can also be found in the Lab Reference Grids.
All printers have common features. The information below focuses on 3 features: the build area, platform and cassette. See a brief description of these below.
The printer pictured below is an M3 Max, but these features apply to all Carbon printers.
Build area
The main functional space of the printer where parts are printed. Operators will primarily interact with components in this part of the printer during daily operation. The major components of the build area are:
- platform
- cassette
Platform
The platform is a removable appliance with a flat surface upon which parts are printed. Platforms are larger or smaller depending on the printer type.
Cassette
The cassette is a highly engineered optical device that is a critical component of the Digital Light Synthesis™ platform. It is a removable appliance that holds the liquid resin used to make parts.
The window must be properly maintained to ensure print quality. Improper maintenance or damage to the window will reduce print quality and may result in failed prints and production delays.
Follow the links below to learn more about printers and cassette maintenance.
L1 Printer
Quick reference document showing the workflow steps.
Before printing parts, project preparation is necessary, known as Print Prep. This involves importing an .stl file into the printer's user interface (UI), accessed via a web browser on a computer, which controls the selected printer.
To create a project for printing, follow the steps below
Note about "Click Print" - This action only sends the project to the printer: It does not start the printer. The print only begins once an operator starts the print at the printer or on the pop-up window that appears after clicking print.
When setting up a build in the Printer UI, start on the left and work your way to the right. After importing your part, begin by selecting a material on the left. Then work from left to right on the top bar of the UI. Finishing on the right of the screen with Print.
Resin must be added to the cassette before printing can begin. One-part resins can quickly agitated and poured. Two-part resins require more precise mixing with additional equipment:
- Cartridges are dispensed by using an electric dispenser and mixing tip.
- Bulk materials are mixed and dispensed with a range of equipment including vortext, overhead and planetary mixers.
- Check the cassette. The window should be clean and free of damage.
- Invert the one-part resin bottle 5-6 times to distribute the pigment.
- Pour the required resin amount into the cassette. This amount is provided in Print Analysis.
- After the build is complete, the resin can be reused, discarded, or saved for later use.
Resin Mixing and Dispensing - Includes information for dispensing two-part resins.
For specific hardware operating instructions, refer to the correct hardware course.
- Open the printer door.
- Install the cassette. M-Series cassettes will contain the dispensed resin. L1 Printers, the resin will be poured into the cassette once installed.
- Inspect the printer platform. Be sure the platform is clean and damage-free.
- Install the platform.
- Close the print door for M-Series printers. For L1 printers, the door closes when the print begins.
- Verify the correct project is queued to the printer.
- Start the print. See various options in specific hardware courses.
- When the print completes, open the door.
- Remove the platform.
- Close printer door.
There are two options for washing:
- manual
- automated
Parts washed manually can be washed on-platform or off-platform. Consult the Lab Reference Grid or the resin protocol for specific process information such as solvent and solvent exposure time.
- Fill a washtub to 75% of the part height.
- Place washtub on orbital shaker. Use the magnets to hold the washtub in place.
- Place part(s) in washtub and secure the lid.
- Set the orbital shaker to the rpm specified for the resin.
- Turn on the shaker and wash for the specified time.
- Remove parts from the washtub.
- Air dry or dry with compressed air or spinner.
- Check the parts. Sometimes touch up cleaning is necessary. Refer to the Basic Washing course for Touchup Methods.
Washing parts on the platform is shown here. Parts can also be removed from the platform before washing.
Tips for Washing Two-Part Resins
- Always wash parts within the pot life of the resin. For best results, wash as soon as possible after print completion.
- Parts do not achieve final strength until bake in convection oven. Handle with care.
Other equipment can be used to remove liquid resin from parts.
Purpose-built washing machines like Carbon's Smart Part Washer, the Formlabs Form Wash and the PostProcess DEMI 910 use solvents to wash parts.
Parts can also be spinned clean using the industrial-strength Heinzen Spinner or smaller devices. Spinning can be especially useful for latticed elastomer parts which are sensitive to solvent overexposure.
The Smart Part Washer provides an automated solution that washes parts on the platform. When the completed build is placed in the Smart Part Washer, this connected device detects the build information and provides a wash cycle for that build.
- Install the platform in the Smart Part Washer.
- Select the preferred wash cycle. The lid closes and cycle begins.
- When the cycle completes, the lid raises. Remove the platform from the washer. If using DPM solvent, dunk parts in IPA 10 times over 10 seconds.
- Air dry or dry with compressed air.
- Check the parts. Sometimes touch-up cleaning is necessary. Refer to the Basic Washing course for Touchup Methods
Each resin has a maximum solvent exposure time. Overexposing parts to solvent will adversely affect material properties. See the protocol sheet for your resin for maximum solvent exposure time.
Parts need to be removed from the platform before curing. This may happen before or after washing, depending on your needs.
Washing parts on the platform can be benificial if parts are delicate or preserving surface quality is especially important. The platform holds the parts in place during washing, preventing surface abrasion or damage to delicate features.
Removing parts from the platform before washing requires less solvent. However, this is recommended for parts printed in tougher resins or where surface finish is less important as parts will bump into each other during washing.
Some materials and geometries can be more challenging to remove than others. For example, elastomeric lattices may require more care than solid rigid parts.
1. Make sure the platform is stable on a work surface.
2. Hold the platform against the work surface.
3. Press the scraper blade firmly against the platform. Always aim away from you.
4. Use the scraper to apply a slow steady force on the part(s) to detach from the platform.
5. Remove supports from the part(s). Touch up the part(s) if needed.
6. Clean the platform. See the hardware (M1/M2, L1, M3) course for information.
Curing sets the final mechanical properties and makes the parts safe to handle without gloves. The type of curing utilized will be dictated by the resin.
- One-Part Resins
- Cure with UV (ultraviolet) light
- Completes the curing process started during printing.
- Two-Part Resins
- Cure with heat (typically called thermal curing or baking)
- Activates a secondary chemical reaction that finalizes the mechanical properties creating engineering-grade material properties.
Most UV ovens project light from the top-down.
- Only surfaces that are struck by light are cured. Undersides of parts or areas that are in shadow are not cured.
- Each part will need to be rotated until all surfaces have been exposed to the UV light.
- Be sure the parts are clean and dry.
- All supports are removed
- No unwanted resin
- Surfaces are dry
- Arrange the parts in the UV oven.
- UV cure each side of the parts according to the Lab Reference Grid.
- Remove the parts from the UV oven with clean gloves.
- Parts are ready for use!
Thermal curing is accomplished by baking parts in a convection oven. Each two-part resin has a specific curing program with custom timings, ramps and temperatures. Some variations of thermal curing include salt baking and inert baking.
- Be sure the parts are clean and dry.
- - All supports are removed
- - No unwanted resin
- - Surfaces are dry
- Inspect any baking implements (baking sheets, mesh, fixtures, etc.) that will be used. These should be clean.
- Prepare the chosen baking implements.
- Setup parts with baking implements or fixtures.
- Place in the oven.
- Bake according to thermal curing requirements.
- Parts can be cooled inside or outside of the oven. A recommended cooling procedure is on the Lab Reference Grid.
- Remove parts from the oven using heat resistance gloves, if not cooling completely in the oven.
- Remove parts from all baking implements (sheets, fixtures, salt). If salt packing was used, the salt needs to be removed from the part.
- Parts are ready for use!
