Sewing Patterns on the Laser Cutter
This is an experiment I did to see if using a laser cutter was a better way to cut fabric for sewing patterns. I was taking an online class on sewing with knits, which are notoriously difficult to work with-stretchy, slippery, difficult to cut and difficult to sew. I found myself dreading the cutting part- anyone who has experience with sewing knows that cutting out the pattern pieces is the most important step, creating a foundation for the rest of the work to go smoothly and for the pieces to fit together as intended.
Getting the Pattern
The pattern I was working with was in the form of a PDF, which is becoming increasingly common for pattern manufacturers. Now, as someone experienced with the laser cutter, my first thought when i hear "PDF" is "vector graphics! I can laser with that!" So I opened it up in Adobe Illustrator, extracted the vector paths for my size, and arranged them to fit the size of the laser bed (the big bed is SO useful!). When I arranged the pattern for the bed, I assumed a double layer of fabric, with the folded edge towards the front so I could easily spot the laser head to line it up with the fold. I deleted the center line of the symmetric pieces so I wouldn't accidentally laser a line down the middle of my shirt.
The hardest step was arranging the fabric so that it would be double layered, smooth and even, and have the grain perfectly square to the laser bed. It probably wasn't much harder than arranging the fabric for traditionally cutting. The honeycomb of the bed was pretty high friction compared to a table, but for slippery fabrics that could actually be an advantage. I turned the fabric with the right sides facing in case the bed was dirty, but it didn't end up being an issue.
Power settings: I did a test box with Power 50/Corner Power 25, and Speed 200. That worked well but with the actual pattern pieces the edge lengths were long enough that the laser accelerated and the bottom layer had to be pried apart. I'd recommend using Speed 100 for more consistent cuts with this fabric.
The fabric I used was a medium-weight jersey, like s soft high-quality t-shirt. I was somewhat concerned about the fabric blowing around with the air assist, but it was heavy enough that it stayed put with no issues-no weights needed. The fabric content was 80% rayon, 15% polyester, 5% spandex, which is ideal for laser-cutting. Rayon is basically processed wood pulp, so it burns just like cutting plywood or MDF. You can see the edge quality on the left. The edges got charred, but there wasn't any discoloration beyond the edge due to smoke. The edges feel kind of...crumbly... like if you rub them between your fingers the char comes off a little. It's possible that with hydrogen peroxide/washing the edge char would totally go away. For my purpose, the edges were all going inside seams, so the edges didn't have to be perfect.
Working with laser-cut fabric
Everything was perfect. The corners... they were so sharp. If you're obsessive like me, you will love it. :-) Update from other projects: The only problem I have ever had is when i accidentally moved the pattern pieces in my file without moving the notches, and ended up with some funny triangle cutouts in the middle of my fabric.
There are so many things I want to do now that I discovered how easy this is. If you get a pattern online, you can laser-cut onto tracing paper or muslin to do cheap, fast fittings. You can modify the vector paths to come up with an altered fit and try it right away. You can design a ridiculously complicated dress (Herve Leger bandage dress, anyone?) and instantly have all the pieces cut out. I might even make a dress version of one of my Voronoi Lamps with fusible interfacing and layers of fabric....