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Fosshape is also a thermoplastic, although it acts very differently. It is a non-woven fabric that looks and feels similar to felt. It is completely pliable and stretchy before it is activated by steam. Once steam hit it it begins to harden and it can never be stretched out of that shape. It can be sewn (many of these materials can, but this is very good for it) and shrinks significantly when it is activated. I have been told it can be as hard as plastic, but I have not personally experienced that.

Fosshape received the most praise amongst my interviewees, coupled with warnings of shrinkage and unique ways to harden the material. I was advised that if I wanted to get this mask made out of Fosshape a good way to do it would be to make a positive and negative mold, sandwich the Fosshape between and have holes to allow for steaming for an hour. I would like to take this chance to discuss molds in general with this project.

I knew whatever costume piece I selected to make it was going to carry some baggage with it, each piece has unique problems to deal with. Masks, I would learn, carry several unique problems including very irregular, hard to get shapes and angles, a problem that can be alleviated by having a good mold. I debated whether I was going to do it for a while, in the earlier parts of this thesis I believed it would have only been for the Fosshape. I asked for further advice from my interviewee who had suggested working with the Fosshape in this way and she gave me very detailed instructions on how to make the mold with the holes for steam. She also added that this was probably a lot to ask of someone inexperienced with molds and that maybe I ought to try it with a smaller piece instead of a whole mask. For the mask she recommended getting a craft iron to help push the Fosshape into the right depths and harden.

I started with a small sample to try out my tools and understand what the material is like.

This all seemed like good advice so I ordered a craft iron and decided I would make the horns in a mold. After school closed a couple times and I had to quarantine myself I sort of gave up on this idea. Making these plaster molds requires space and materials that I did not have at home and the whole thing felt like opening a can of worms as I have zero experience in it. If I were to start this thesis all over I would have started with a lengthy mold-making process and made sure I had a positive and negative so I could use the molds however I like. It would have been handy on several occasions, but at the time I didn’t fully understand that.

Starting to pin in the Fosshape

When I began pulling the Fosshape over my clay mold I immediately understood why crafters like it so much, it is truly magical to have a fabric form to whatever’s below it without needing darts or any manipulation. I enjoyed it’s incredible flexibility. I had been advised to pin it so I used some tiny pins and tried to pin it down as best I could. The places where I had no clay weren’t pinnable which was unfortunate, but my clay wall did help somewhat in this.

The way I could pull it over every bump with no trouble was just delightful.

Fully pinned, this is after some steaming, which sucked the Fosshape down to the mold.

Once it was pinned I turned on a hat steamer to begin steaming it. Fosshape takes steam and pressure to become hard, many of the videos I watched used normal clothing steamers that they actually touched to the Fosshape. I think this may be more effective than just the pressured steam coming out of the hat steamer. I found it was very furry and while it was getting harder, it wasn’t turning into the plastic I expected. So I brought out my brand new craft iron.

One of the delights and horrors of this project has been figuring out new tools. There are a lot of tools I used for the first time while doing this and there have been some accidents, but overall I’m pleased to be adding more ways of working to my arsenal. The craft iron is like a lower heat soldering iron with bigger tips designed for delicate pressing. It has several interchangeable irons with different shapes and sizes.

I found at high heat this made the eye socket well, but it also burned it a little, leaving residue on the iron. Eventually I learned that I needed constant movement to not have hairs individually stuck to the iron.

I attempted to use the hot knife setting to help push down the Fosshape in the tighter areas, but it only drew a plasticky lin.

I found the side of the small iron tip made groove very well, though it made a sharp edge on either side that I would need to smooth tip with the round tip.

After experimenting with them I found I liked the rounded tip for most needs as it has no hard edge on it. This tool was very useful, when I swiveled the ball around on top of the Fosshape I could see that it was melting the outer layer creating a hard plastic shell. I ran it around the whole mask, sometimes using the iron shaped tip to do some of the flatter areas. As I kept working it, trying to get it harder, I noticed that my touches were now singeing the Fosshape and creating little craters and valleys wherever I touched. I had thought the iron had reached maximum heat after about 15 minutes, but at 30 minutes in I was seeing something different entirely and realized the heat was probably far too high for the Fosshape. In addition to that, my iron looked destroyed and covered with sticky gunk.

Probably should've turned down the heat long before this.

I tried cleaning it while it was hot with a rough towel and some water. I tried cleaning it when it was cool with my nail and acetone, no change. I tried to look up online how to get Fosshape off of an iron but came up empty. I figured even if it was a bit different it ought to act like a normal iron, so I ordered some EZ-Off (a magical iron cleaning product) and waited. When it came I was shocked and delighted to see all the stuff come off of it. It definitely took some elbow grease, and just as I was almost to the end I grabbed it the wrong way and laid my thumb down on the hot tube in the middle, and that was all the work I did that day.

Ow ow ow. Miraculously I only got two burns during this entire project. This was a bad one, not only was it very painful but I was terrified I was going to not be able to work because my thumbs are so crucial to forming work. In my worry I ran my finger under cold water for nearly 15 minutes instead of the brief cold wash rinse I usually do when I burn myself. I took the rest of the day off and fretted about it healing. The next day there wasn't a blister and it only hurt with excessive pressure. I will forever remember this (you remember it too!) and be sure to run my burns under water for a good long time.

Throughout working with this iron I just kept a wad of fabric with EZ-Off in it and cleaned it as I went. It worked out really well, the only problem is I did not pay attention to the fact that the EZ-Off definitely says to use it in a well ventilated area - I’ve never worried much when it was just for a minute in a shop once in a while, but I used it a lot and my throat felt it a little. I set my craft iron to medium instead of high and got back to the Fosshape.

I decided to add patches into both cheeks as the Fosshape had shrunk significantly. I was able to do this by just using the iron to fuse it.

Ready to be pulled off. This picture makes me a bit sad because it was probably the best it looked, the hardening process got a bit ugly.

When it seemed a bit hard I pulled it off so I could steam the inside. When I had done the outside I had stopped using steam and just used the iron but I found when I used both on the inside it gave the nicest effect.

Steaming the inside over the steamer. I should have been wearing safety gloves while doing this and in the many times I did following this, I did wear gloves.

I would steam an area thoroughly and then use the iron on that spot, making the water sizzle. This worked well for matting down the fuzzy Fosshape hairs as well as hardening. I worked several areas in the back, when I turned it to look at the front I was dismayed to see a strange dimpling had happened in the areas I worked. I don’t know why this happened, my best guess is that on the front it did not get enough steam so that there were soft bits, then when the back was hardened those soft bits shrank, making the indents from the iron much more severe. I tried to fix this many times with the iron but nothing seemed to help and if anything I made it worse.

So sad. This eyebrow suffered the most from this dimpling.

On top of that I found the mask had gotten much wider while steaming, I steamed the inside really well and then pinned it back to the form hoping it would go back to hugging the face. I steamed this mask a lot. I think there were at least three days I worked on trying to get it hard and smooth. I can completely see how a mold would have fixed all of these problems but I did what I could to make it work. I also decided this would be a good excuse to see if a heavy primer like thick gesso could really forgive all my sins.

This stitched horn looks a bit like a ghost! It looked terrible when done.

When it came to the horns I first cut pattern pieces the same as the other materials, but just one horn because I was going to try something new. I wanted to try stitching the Fosshape and then steam it to fit the mold. I stitched it a ¼ inch into the seam allowance to allow for shrinking and decided to leave the seam allowance on the outside, thinking I would iron it down when it was done. I put it on the foam clay horn and over the steamer. It did not shrink much at all, it wasn’t tight to the horn and the whole thing looked pretty silly. After speaking with Ellen I decided I would scrap my original patterns and forget about sewing it as she said it was easier to lay one side over the other and fuse it anyway.

Sometimes draping is just the best choice. It is here that I started fantasizing about at least one of the masks having a fabric drape on the horns to give it a horned hennin look.

I pinned it and then steamed just a bit. It was enough to then take the pins out and have the Fosshape stay in place for further steaming.

I draped a piece of Fosshape over the horns and pinned it closed and cut out that shape. I then pinned the seam closed around the horn mold and put it in the steam. It was in doing the horns that I realized that the hat steamer I was using has very different pressure depending on how full it is. I had just filled it up and I saw that it made a huge difference in the Fosshape, hardening and shrinking it quickly. After a quick steaming I took the pins out so they wouldn’t leave a mark, but the Fosshape was already held there and I used the iron to fuse it. I steamed the whole horn and used my fingers to smooth it down and then took the iron and rolled it along the horn.

Smoothing the seam of the horn on top of the foam clay mold.

Because of its easy shape I could do this smoothly and had none of the bumps I got on the mask. This process took longer than I would’ve expected, but having the steam on full blast and being really gentle and methodical with the iron led to a nice result. I left the horns still fuzzy as over working the mask had been problematic.

It just didn't really work.

Attaching the horns proved to be very difficult. I think that perhaps because the mask of the Fosshape was already hardened it wasn’t possible to fuse the base of the horns (which I left soft on purpose) to the mask well. I was able to get parts of it to fuse using the iron, but I krazy glued down most of the base of both horns.

Didn't expect to be using krazy glue so often but it did the trick sometimes.

I picked krazy glue because I had just been using it with the TranspArt and I couldn’t find any glue information on glues for Fosshape online. It worked well, but it is worth pointing out that if krazy glue is heated to over 350 degrees it releases cyanide. I didn’t anticipate that it would ever get that hot, but it was important to know! Once I had cut out the mask I was able to fuse the two edges by running my craft iron along the edge on high very quickly (so as not to burn).

I flattened the horn bases as best I could with the iron.

After it was cut out I continued to harden the back of it by putting it in the steam and then using the craft iron on high. On high it was likely to burn if I was slow but it seemed to be the right temperature to mat down the material and get some of the plastic hardness I was looking for if I moved quickly.

After painting (please see painting section for what I did) I lined the mask in felt and used an awl to make small holes for the elastic.

I had a hard time with Fosshape, but I chalk that up to inexperience and experimenting alone. I know if I were in a room with other crafters this mask would’ve turned out better. I spent lots and lots of time trying to harden it and I must not have been doing it with the best technique at least some of the time. I never got it as hard as plastic, but I believe it is possible to do. I was impressed with the way it formed around tight curves and shocked with how light it is. It is the lightest mask in the group by far, feeling like a piece of paper in the hands. That is an unusual quality for a material to have and I look forward to someday making something in a two-part mold out of Fosshape to be amazed by the ultralight plastic I have made.


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