oh my gosh how serendipitous, ive been trying to comb the internet for swimsuit costuming help for a princess daisy and princess peach cosplay for a water park convention next month!!! i cant seem to find anything actually decent or understandable, & im kind of a dummy, so would a swimsuit question fall under stretch knits? or is spandex or lycra a whole nother ballgame? :0 im rly bad abt making costumes with the right materials but im trying to get better.... eek! thanks in advance for any help
Glad this week’s theme is useful to you!
Swimsuits are usually made of stretch knits, yes. I will use this opportunity to talk a little bit about choosing fabrics for bodysuits and similar garments, since that seems like it would be most helpful to you.
Stretch fabrics come in two basic forms – 2-way and 4-way. 2-way stretch means that it stretches either side to side or up and down, but not both. 4-way stretch means that it stretches both side to side AND up and down, though one of these directions may have less stretch than the other. (To make things extra confusing, some places call what I’m calling 2-way stretch “1-way stretch” and what I’m calling 4-way stretch “2-way stretch,” so always double check that the fabric has the stretch you need.) For something like a bodysuit, which goes around the body in multiple directions (around the torso horizontally, as well as around the torso vertically, or in other words, around the waist and around the area from crotch to shoulder), 4-way stretch is best because it will more easily move with you. I’m assuming that since you are wearing this to a water park (Colossalcon?), you will be actually swimming in it, so 4-way stretch is vital.
When doing most bodysuits, the direction of greatest stretch should be around the body horizontally, to allow for greatest fit. However, when doing a gymnastics leotard, you will want to have the greatest stretch up and down the body, so that there is greater freedom of movement. For a swimsuit, I would recommend having the greatest stretch around the body horizontally.
When looking at bodysuit fabrics, there are two major factors to keep in mind – stretch and recovery. Stretch refers to how much the fabric expands when you tug on it, and is measured in percent – if it stretches 15%, it becomes 15% larger than the relaxed fabric, if it stretches 50%, it becomes 50% larger (so if you have a 5″ piece, it becomes 7.5″), and if it stretches 100%, it doubles in size (so if you have a 5″ piece, it stretches to 10″). For a bodysuit, you generally want stretch above 50% at bare minimum, and stretch above 75% is best. Recovery is also very important, and a bit harder to measure objectively. This can only be tested through observation and experience. When you stretch the fabric and let go, how quickly does it snap back to its original size and shape? Does it stay somewhat stretched-out looking, or does it go right back as if nothing happened? Something like a T-shirt and many light rib knits have lower recovery, making them unsuitable for bodysuits because they will eventually sag, and performance knits meant for bodysuits, leotards, and swimwear will have high recovery, so that they conform to the body. Increased spandex content increases the recovery of a fabric.
Most performancewear fabrics are made of a synthetic like nylon mixed with spandex. Lycra is the brand name of spandex, and elastane is another name for spandex (often used outside the US). These are all the same fiber type. When people talk about making a costume out of “spandex,” what they mean is using a knit fabric with a high spandex content, typically one that is opaque or otherwise solid, with a smooth finish, and a high amount of stretch and recovery. You will often run into “regular” spandex, which is usually raschel-knit, a process that allows for a great amount of stretch, as well as materials such as milliskin, moleskin, and other, more speciality fabrics under the same “spandex” umbrella (satin spandex, some wicking knits, mystique spandex that has a coating of tiny metallic dots for a shiny effect, wet-look spandex, etc.). These may all have slightly different properties, depending on knitting process, fiber and needle size, and fiber content, so it is always best to get a swatch and test the material yourself if you can.
For a swimsuit, you are likely going to want to line it. “Swimsuit lining” fabric is usually a lightweight tricot knit (tricot is a different knitting process that creates fine wales on one side) in various neutral colors and a small range of skin tones. This is usually used in the crotch and sometimes bust of the swimsuit. Various 4-way stretch meshes are also used as a lining, and something like a light or medium powernet (powermesh, girdle fabric) used as a full liner can help create some light shaping properties. A heavier tricot knit can be used as the outside material.
With anything that is going to be used as swimwear, be sure to test it in both water and chlorine ahead of time, if you can. Some fabrics will become faded or damaged by pool water, and that’s not something you want. (Materials with a metallic foil coating will often fade quite fast, for example.)
For your purposes, I would recommend looking at either a heavier tricot knit or a “regular” spandex. Either one would work well for a swimsuit. Be sure to get a good pattern so that you have the correct amount of ease (likely negative ease) and that you get the proper notions (swimwear elastic is a big one here).