A customer of mine designed a cake for her wedding. It's a 4 tier cake, 14" 12" 10" and 8" round. She wants to have an edible music record sticking out of the side of the 2nd and 3rd tier, it looks like a half moon on the side of the cake. I'm just not sure how to pull this off. Maybe make a gumpaste record and create slats in the side of the cake and insert it before icing the cake? (It's not a fondant cake). Would the gumpaste absorb the moisture and become soft and loose it's shape? Will it be too heavy and fall out? Would a half moon be better? How do I support it? Thanks!

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Thanks, Ropalma. Those links will help for making a vinyl record but I'm more concerned about supporting a full sized vinyl record that will be standing vertically, not laying down, and it will be sticking out the side of a cake. I think it will just fall out. Especially a full-sized fondant record, that will be heavy, no? What about chocolate? Chocolate could break? Or black sugar glass? Would that work? How heavy is sugar glass?

No other thoughts?

AIf it doesn't have to be completely edible or needs to be transported, I would probably cut a segment from a cake card board so that it can stick out of the side of the cake as the record. Then add some skewers to attach it to the side of the cake, and decorate the card to look like a record.

If I felt like taking the risk, I would cut the record from gumpaste, insert a couple of skewers and let it dry completely. Decorate away, transport separately, add to cake at last minute.

Another thought Rice Krispy treats?  But I agree with winniemog.  If you do not need for it to be edible you can use card board.  Sometimes we get too hung up on everything being edible.

RKT is going to be too bulky in my opinion. 

And I've just read your original post again, I would be quite worried about the fact the cake is buttercream. I am a complete control freak, and I wouldn't do this cake unless it was in fondant, but that's because that's where my experience lies. I would want to experiment with this precise setup, with my own icing in place, to see how the record decoration reacts to my icing. I don't know how your buttercream will affect gumpaste decorations - so I would not be placing the record piece until the last minute if possible, and I would have tested it out first. It has to stand up for the whole reception, I am imagining!

I still think a fondant-covered card board piece with skewers is your best bet, especially given your scenario. But I wouldn't be trying this myself, I would insist on fondant-covered cake for my peace of mind! 

AI made a surfer cake and had the wave made out of gum paste. After the gum paste had dried, I placed it (the wave) on the cake and covered it entirely in buttercream. Was even standing upright after 12hrs. No problem. Not sure about the weight pulling down on the cake if you push it in horizontally... Why don't you just make a small trial version? I'm a control freak too and guess that would be the easiest way to find out if it could work.

Melt chocolate (or candy melts if you don't want to temper).Make a parchment or wax paper circle to put in the size of cake pan you want.. Pour the thickness of record you want in a round cake pan, tap to 'burp' the air bubbles. Use a cake comb for the grooves just before it sets up. Let it set up. Slide it in, (make a couple of spares)

ps   Or a tupperware or butter lid, I used a shortening lid for mine.