There probably isn't a way of saving that one, but put it down to experience and try another sample. You need to achieve either a 'ply' situation - imagine the card base as the middle of a sandwich, if you put something on one side (pm) you need to put something - simple strip pm, for example, on the other side. Glue isn't enough on its own, and even then you might still have a problem. You could glue three sheets of corrugated card together, then cut out your frame, have the middle sheet corrugations going the opposite way to the others, that should hold rigid when you pm it.

Alternatively you have to create either folds or bends in the card to make it rigid. For a straight sided mirror you could create 'square tubes' for the sides, which will remain rigid (you really need pictures to explain this!) or if you want a shaped mirror frame, cut profiles out of thick corrugated card and glue them across the background shape (on edge) then when dry, pm between the profiles. I suspect that only makes sense to me! Good luck.

hi yul,
when i work with cardboard i usually cover it with a layer of masking tape to prevent warping and then apply strips over that.

Hi yul
when you say base do you mean you have backed it with carbooard ?.
I make alot of mirrors (susan Oldfield in the gallery page 1) After one mishap with carboard I always back them with hard board and papier mache over. you can make box frames for mirrors using cardboard but use a stiff thick card like packing boxes and as EllenEggers said use masking tape to tape it up.

Sue.

Last edited by snoozysnowshoes (2007-08-25 16:32:10)

Hi, Aquarius,

Thanks for your reply and advice.

yul

I intend to try coating cardboard or masonite with true shellac before I start adding the papier mache. Shellac is non-toxic when dry, its base is alcohol, and although not truly waterPROOF, it is highly water-resistent. I will be applying it to both sides to try to prevent initial warping.

Sue