At the last Sandown Park knitting show, I purchased a solid crocheted box. I was intrigued, and started investigating ways to stiffen crocheted or knitted fabrics to create solid useable objects. The ladies at my local machine knitting club all knew about starched knitting, so I conducted a literature search, and found one book on the subject: "A Ticket A Tasket Let's Knit A Basket!" by Margaret Parker. It is a short booklet that provides some knitting machine patterns which can then be starched, and some suggestions on which starches to use.
The book suggests using potato starch or corn starch, but I have been unable to locate a source for either in our local area. I did, however, have some Arrowroot in the cooking cupboard, which has similar thickening properties. Let the fun begin!
My first test has been a very strong 1:3 Arrowroot solution. 1 tablespoon of arrowroot, mixed with 2 tablespoons of water. Bring to the boil, then allow to cool, whilst stirring thoroughly to stop any lumps appearing. Then, dunk the knitting into the solution and allow to soak for a while, agitating frequently. I used a tension square of two-colour fairisle. Wrap a ramekin disk in clingfilm, then squish the wet knitting over the bottom of the dish, stretching it to match the shape of the dish. Leave over-night to set. When it was fully set and dried, and cut the excess knitting away, and here are a couple of photos of the result. I was pleasantly surprised. More investigation is required of different yarns with different strength solutions.