Introduction to vacuum casting
The 3D prototypes resulting from this technology come from the creation of a silicone mold which results from a master model first made in Stereolithography .
The silicone mold created with the master model will then be filled with Polyurethane resin, using a specific vacuum casting machine.
The life of the mold can range from 6 to 30 parts; it depends on the geometry of your parts and the polymer used.
This technology is therefore ideal for pre-production or low production runs that will have the same appearance and mechanical properties as the final product.
The printing dimensions of our largest machine allow us to produce parts up to 1300 x 750 x 800mm.
The benefits of this 3D printing technology
- Possibility of using flexible, transparent, rigid materials with mechanical and thermal characteristics similar to those of standard materials
- Numerous finishes
- Possibility of overmolding and addition of inserts
- 3D part dyed in the mass
- Large panel of technical resins
- Flexible / rigid bi-material moldings
Vacuum casting materials and finishes
At Axis, we use the following materials:
- Flexible materials – Elastomer: from 25 to 95 Shores A
- Rigid Materials: close to ABS, PA, PP, PC, HDPE
Do not hesitate to contact us for your specific needs, you can also consult our material sheets. Vacuum casting allows us to have a very flexible offer according to your needs in terms of materials and colors.
Once your parts are produced, we offer the following finishes:
- Complete deburring of parts and assembly validation
- Realistic surface finish: glossy, satin, grained, frosted…
- Painting finishing
- Assembly, addition of inserts…
Deadlines and part design tips
For the vacuum casting process, it takes 4 to 6 working days to create the mold, then production of 2 to 3 pieces per working day. Please contact us to get the exact time frame for your project.
For the dimensions of your parts we are able to respect the standard NFT 58-000 normal class
Vacuum casting in pictures
How does it work?
Step 1 : First of all, a master model must be made in
- After receiving your 3D file, we process it, program it to launch it in production while applying or not a withdrawal according to the ordered material.
- The master model is launched in production using the Stereolithography process
- It is cooked to be hardened.
- The 3D part is cleaned, sanded and blasted. The necessary finishes are provided by our prototypists, because the molding will have to do with the appearance of its master (graining, transparency, etc.).
- Our mold makers stick a mark along the joint plane to facilitate the opening of the silicone mold.
Step 2 : Making the mold
- The master in Stereolithography is installed in levitation in a wooden box with the help of a sprue (recycled feeder sprue, which will allow the material to circulate in the cavity of the mold) and vents (to evacuate air from the material)
- Once the part is installed, the silicone is then poured into the box to take the impression.
- When the silicone has hardened, our mold makers open the wooden box along the joint plane.
- After fully opening the silicone mold, the Stereo master is gently removed to avoid damaging the silicone.
Step 3 : Realization of the duplication
- The casting operator in charge of the project carefully closes the mold manually, while avoiding leaving any space which could allow the polyurethane material to be released soon into the mold.
- He installs it in his machine, prepares the two materials to be mixed separately and places them in the machine in the high position.
- The machine is closed and put under vacuum while mixing material A (isocyanate) and material B (polyol). The two materials are incorporated into each other under vacuum and then poured into the silicone mold using gravity.
- When material comes out of all the vents created, the air is returned to the machine, and the filled mold is placed in a hot oven for several minutes while waiting for it to harden.
- Once the material is hard, the casting operator demolds the part