by Yun-Han Lin
A sneak peek of the procedure before we get started!
Preface
As some members at our studio were trying to develop products using leather molding, it occurred to us that we could use 3D-printing to produce molds for pressing logos on leather. We made improvements based on the work in an article and the process was as follows:
1. Producing molds
- 3D-printed models using Fused Deposition Modeling (FDM) turned out to be like the one in the article. The trace marks on the prints were deeper and harder, which made it difficult to polish or decorate their surface. Therefore, we decided to opt for a light-curing 3D-printer.
- To remove the support material on the prints, the surrounding frame of the printer needed to be separated so that the logo was printed facing down; otherwise it could cause cupping on the prints.
- We tried to build the mold with three thickness: 5mm, 10mm, and 12mm. We arrived at 12mm, given that the print surface had to be sanded, and the deeper the engraving on the mold, the better the logo will turn out on the pressed leather, , as shown in the video.
2. Preparing leather
- We used vegetable-tanned leather that can be softened and reformed. This type of leather features its light brown surface and it is oil-absorbing, breathable, exceptionally water absorbent. Also, it becomes softened after water absorption.
- The leather in the video was the 1~2.5mm thick primary tanned leather. Almost all thickness would do, but the thicker the better.
3. Cutting
- Leather can be cut into the desired shape using laser-cutting or a utility knife.
- Check out: Using Laser-cutting for a few tips.
4. Soaking
- There are burn marks from laser-cutting on the edge of the leather, often with some dust of carbon fiber. It is advised to soak the leather and remove the dust with a brush.
- After brushing, soak the leather in water for about 30 minutes so that it softens.
5. Stamping
- Take out the soaked leather from the water and gently press it against a dry cloth to remove the water absorbed. The water pressed out from the edge shows that the leather has absorbed enough and is ready for stamping.
- Put the leather onto the mold, with the smooth side facing the logo on the mold. The second piece of the mold goes against the rough side and press both molds with a fixture till a small amount of water is pressed out.
- Let it sit for an hour.
6. Demoulding
- Take out the leather, and let it sit in a cool and ventilated place to completely dry up before proceeding to the next step.
7. Edge work
- Burnish the edges of leather with a slicker.
- If you use a utility knife and the leather edge ends up messy, you can use 600-grit or 1000-grit sandpaper to smooth it out first.
8. Hanging ornament
- As a final touch, string the piece of leather with imitation leather cord and it becomes a hanging ornament. Bronze keychains from handicraft material stores can also make a good match!
