Troubleshooting Fosshape

[mountmaker289]

Curious to hear about experiences using Fosshape for making invisible mannequins on this forum. I've read various accounts online of mountmakers successfully using Fosshape to fabricate mounts. I've also studied tantalizing photos of gorgeous invisible mounts made using the material.

However, I have only had medium success using Fosshape. The main issue is buckling/torquing due to compression [esp. from knit bathing suits] or weight [for ex., large gowns]. The only remedy seems to be completely filling/reinforcing the interior of the mount with carved ethafoam insertions.

Have others grappled with this issue? Is the answer to simply back the mount with carved ethafoam disks? Or is the issue the use of a steamer vs. heat gun [for ex., would a heat gun 'set' the Fosshape harder?]

[Jamie Hascall]

I found that Fosshape was a material that had "just enough" strength to do the job, but you really had to look at where the weight and stress was going to land and design with that in mind. One layer of Fosshape was usually insufficient through the shoulders and the chest areas so I would usually make a sleeveless vest that would go on first, and then put my main body shape over that. The heat would fuse the two together to give a pretty stiff shape, but care would be needed to not buckle the fabric when removing the underlying form that it was shrunken to fit. Ethafoam bulkheads were then used to give strength to specific areas, and to provide a structure for support poles etc. For free standing shapes such as a strapless bust line, it might be useful to bend aluminum or other metals to provide a supporting batten to the shape and enclose it between two layers of Fosshape.

I tried both steam and heat guns with Fosshape and found steam to be far superior due to its ability to penetrate the felt. Dry heat tends to shrink and fuse the outer surface before it effects the interior of the fabric. That said, experimentation is key in finding new ways of working with a material that has barely been explored. A tacking iron, or regular iron may give good results when you need a really hard fusing of the material.

It would be helpful if you could post specifics and pictures of what you're working on and see if we can come up with ideas to achieve your goals.

Let's keep the discussion going and see if we can find a new tactic to solve your problem.

[jwilliams]

When I am making the pattern I try to include several "darts" to tuck in excess material and also provide a rib structure. I've not had an issue yet with heavier things buckling the form. A steamer is the recommended tool for shrinking, and take your time to really get it down to its minimum dimension. The material can buckle when removing your form, and that does create a weak spot, but it can be resteamed to firm it up - just be cautious so you don't lose your shape. Photos would definitely help!