I have to do a grooms cake that looks like a cooler of beer. How do you make the ice cubes?

I've never made one, but the first thing that comes to mind is that you could use clear gelatin in ice cube trays.

I'd look for one of the pictures from someone who has made one and IM them the question.

I think some have used rock candy but that is how I'd go about finding out. There are several on this site who have made them.

I made a beer cooler cake - I haven't posted it yet - I made my ice cubes out of clear jello. I used the jiggler recipe and they held up great when I made the cake for during the summer.

Hi there, I have used both knox and rock candy. My thoughts, Rock candy can be expensive and I did not think the look was right, I used the Knox and tried the ice cube trays and it did not set up so well, Then I used a square pan poured in the Knox about 1" deep and cut into cubes after it set.I found that this held up well,and after a test on the counter 18 hours it finally started to weep a little.was not worried about 4 or 5 hours on the cake. My ice cube cake is in my pics. Good luck.

Wouldnt they get runny and melt into the cake?

This is a very good question, I made a beer basket (posted in my pics) and I resulted to using ice cubes that I found at walmart, although they were very heavy and I had to be very careful when I positioned them so that the buttercream would not get so smushed (if that is a word ). I would think that the clear gelatin would melt on to the cake or at least flavor the icing a bit .

Nope, no melting or funny flavor, I put them on the cake at the reception at 12 noon and the cake was cut at 5:30 and was told that the cubes and cake both held up fine.