You need to change your embedding medium. The differences in viscosities between Araldite and Epon is so great that muscle tissue may act as a diffusion barrier to the Araldite, thus allowing the seperation of monomers before polymerization. I personally would abondon that formulation for that purpose, but if there were reason not to, I would take other measures. Please call me if you cannot get the paper or have further questions. Take some of your wrinkled sections, soak the slides in water for 30 minutes or so, dry off the slides with tissue paper.
Place slides in a rack.
Put the dish in the bottom of the jar and cover the dish with a piece of large filter paper. Put the inset of the vaccum jar back in place. Grease the rim of the lid well and close. Gradually pull a good vaccum on the jar. Leave the slides for 48 hours.