Fold Moulds

 

These moulds are available in stainless steel forms in various sizes

You can create your own mould for self-supporting display items. Fibre board and vermiculite board are suitable.

 

I chose 25mm/1” fibre board because I had a suitable piece lying around. It is possible to use thinner fibre board, but the thicker board is more likely to resist deformation over a long use period. The 15mm/0.675” board is suitable for light use. These do not need to be rigidised unless you desire to for a more robust structure. They do not need to be kiln washed unless you feel a better surface will be achieved.

Angled Surface

The 25mm/1” vermiculite board is more durable. It does need to be kiln washed to avoid glass sticking to it. Otherwise’ it is treated just the same as the fibre board.

The width and length of the board are determined by the width and length of the piece you are currently making or envisage making. You can make it longer than current needs and use a stop of a piece of fibre board or other kiln furniture to ensure the glass does not slip down the slope. This allows you to adjust the mould to different lengths for a variety of projects.

Both materials need to have an angle cut from one end. This is the end that will be elevated. It allows the glass to bend directly from the end of the angled board. This angle does not need to be more than 30 degrees from vertical, as most self-supporting items have angles of about 15 degrees or less.

Support

Then a support piece needs to be made. If it is not of fibre board, it needs to be kiln washed to prevent the glass from sticking. This support needs to be as wide as the angled board. The height of support will determine the angle of the finished piece.

It needs to be aligned vertically and directly under the top of the angled board. A try square can help with this alignment. This support also stops the draping glass from curving under the top. It would be interesting for a rocking horse kind of item, but not for a stable decoration.

The support under the elevated end can be made to various heights to obtain various angles on the piece. Also, different heights of support will be required to maintain the same angle on different lengths of the standing piece. This makes the home-made mould much more versatile than the steel ones.

The Stop

The stop is a piece of kiln furniture placed on the slope at the end of the glass to ensure the glass does not slip down during the firing. It is not fixed to the sloped board so that it can be repositioned. If you are using fibre board for the slope and the stop, you can pin the stop to the sloped board. Or you can use heavier kiln furniture, propped as appropriate to form the stop.

Firing notes

Glass lengths

The length of base in relation to upright needs to be determined before firing. You can, of course, cut the excess base length off after firing. I make the base to be the same length as the top leans back. This ensures the piece will not become top heavy.

A spirit level can be used to determine how long the support needs to be. You already know how long the sloped piece of glass is. Place the stop at that distance from the top end of the sloped board. Use a spirit level to indicate the length the base will need to be. When levelled, make a mark on the support. Then measure the distance from the mark to the top of the slope. That length plus the length of the sloped glass will equal the total length of the flat glass.

Scheduling

Use a moderate ramp rate for the thickness of the glass. The top temperature should be about 650˚C/1200˚F. Set the soak time for an hour. Peek frequently from the start of the hold to be sure the glass has draped vertically. When it has advance to the next segment and proceed to anneal.