Okay This is driving me crazy!! I hope someone can solve this mystery...

Approximately 8 years ago I was doing a lot of stacked wedding cakes. I used the old Wilton Recipe with the ratio of 1 1/2 cups Crisco and 1/2 cup Salted Butter with 4 tablespoons milk, 2 teaspoons vanilla 1 teaspoon almond and a 2 lb. bag of Domino's10X Power Sugar. 

When I stacked my wedding cakes I used the Wilton smooth white opaque plastic plates that took the big white plastic hidden pillars that you could trim to use for each tier. I would bake on Wednesday, Crumb coat on Thursday, Ice/Stack and Decorate on Friday. Keeping the tiers in my refrigerator in between each step until I delivered. My buttercream cakes where very smooth, level and never cracked, nor had any blow outs (bowing). I did this for 10 years.

I stopped baking and decorating cakes and took a very long break, now after 8 years I have begun to bake and decorated again! I truly missed all the fun I had making cakes. BUT I am going crazy tiring to figure out why this is happening to me now.

I updated my recipe slightly to 1 cup Crisco and 1 cup Salted Butter, and 4 tablespoons of heavy cream. I also updated how I stack my cakes... I use 4 cake boards for my base which makes the base 1/2 Inch thick, I also put another cake board under the bottom tier. I use 3/16" Foam Core Board with a cake board on top of that on all the other tiers and then support them with the fat "Bubble Tea" straws and a wooden dowel rod that goes through all the tiers in the center (sometimes two depending on size).  

I do not have any problems when creating cakes that are not stacked.

BUT if I stack just one cake on top, I get this cracking or wrinkling on the top tier. 

I changed my shortening last week after reading a post to one that had some Trans Fat and it still happened, plus way more air bubbles! I did a 3 tiered cake that had this wrinkling on the top 2 tiers and a single wrinkle on the third tier.

I tried putting adding more liquid, but then the icing wouldn't crust. I tried putting a tile on each tier to get the air out and help in settling.

I also now do a very stiff dam of icing when using a filling and nothing has helped.

The only thing I do differently is after I have stacked the tiers and start to decorate them, I don't put it back into the refrigerator because my bakery seems to be warmer and I don't want the cake to sweat.

It just looks like the cake on the inside is shrinking and the icing starts to wrinkle on the outside.

The last cake I did, was fine... then after 2 hours of decorating and I was finishing the top tier when I noticed it had the same problem  :( 

The only thing I think it could be is the supports?? yet I read that what I am doing should be plenty of support. I am thinking of trying 2 - 3/16" foam core boards instead next time and perhaps a masonite board under the 4 base cake boards. (which now that I think about it I use to do 8 years ago.)

Any insight is very much appreciated!!! If someone helps me solve this I will send you a cake decorating gift!! Seriously!

Blessings to you and yours,

Kimberly

Hopefully you can see what i mean in these photos.. I smoothed the last two photos out before delivery, they were just as bad as the first photo. (click to enlarge)

AI don't know how much help I can be. I will try. Now don't hold me to this though. Haha. It does almost look like your cake is shrinking. How log is he cake sitting before you start decorating it? Maybe that has something to do with it? Or maybe the recipe for your new icing? Wish i could

AOops. Sorry. Wish I could be more help.

ADon't know if this will help. I used to use an old Wilton buttercream recipe. I found it was too crusting. The slightest movement, & it wrinkled especially when stacking.

I would go back to your old recipe so you can pinpoint where your problem is. It sounds like you changed a lot of things so it's hard to say what the problem might be. 

Your icing crusted, the board flexed, and there are hairline cracks in the crust of the icing.

Adjusting the consistency of your icing to be a little less stiff should help reduce the cracks..

Refrigerating removes moisture... it's drying it out.

I always bake on Wednesday, let the cake rest 24 hours, then crumb coat the next day (Thursday). In the past I wouldn't ice the cake until Friday, I would let the crumb coat rest a whole day. Now after crumb coating I let it set up in the refrigerator for several hours then ice each tier separately and return each tier to let the icing set up for several hours before stacking and decorating. I am wondering if keeping the tiers in the refrigerator while they rest is the problem... that chilling the layers isn't allowing the air to escape... perhaps because the tiers come up to room temperature while I'm decorating it causes the shrinkage?

Let them sit at room temp and see, it's probably got something to do with it. The icing is probably drying out in the fridge.

Ok, I'm seeing it differently.  The wrinkling is just around the bottom from what I can see so the icing is moving ever so slightly.  Everyone had terrible trouble with the new Crisco and if you go to their site they suggest the following fix, add one or two heaping tablespoons of plain old white flour to each icing batch.  It works beautifully.   If it was truly drying out in the fridge, you'd have wrinkles all over the cake not just at the bottom.

Okay I will try adding the flour, should it be just plain flour or cake flour?

Go back to your original recipe, and make your changes one at a time.  The fact that it's happening at the bottom of your tiers might have something to do with the boards moving or the icing being too dry.  I have always heard to add corn syrup to prevent cracking, but I have never had that problem.  I also refrigerate all my cakes with no problems.  My recipe is very slightly crusting so I don't rely on the crust to get the smooth finish.  But I know when you have recipes that crust a lot, you might also see a lot of cracking.

I do remember stacking my cakes on sight in the past and having to be very careful. The icing was not as dry/crusted as I see it now while decorating. The surface feels dryer.

What is your exact icing recipe?

2 sticks butter, 1 cup Crisco Shortening = 2 cups, 2 teaspoons of flavoring, a 2 lb. bag of Domino's Powdered Sugar and 4 tablespoons of Heavy Cream.

I am thinking of adding more either shortening or changing to a high ratio shortening, my local food supplier carries Wesson Quick Blend in 50 lbs as well as Sweetex in 50 lbs. I just didn't want to have so much at one time due to limited space.

oh yes, my butter is soft and my heavy cream is cold.

Keep in mind, it is winter (well, you wouldn't know it right now haha).  If you are running your heat it can also suck the moisture out.  You either need to add more liquid or more fat. 

The difference between High Ratio and reg old crisco is flexibility. (not chemically, just performance-wise). 

Crisco has changed a lot over the years, and my guess is that putting all those other things aside, you just can't do the same things with Crisco as you used to. 

Try high ratio, but be aware that you may need more powdered sugar than usual, as it absorbs sugar better than crisco. 

Just my 2 cents. 

Yeah I definitely don't advise subbing high ratio 1:1.  It ends up very heavy.  It's like drinking heavy cream when you were expecting skim milk.  It's almost chewy (blech).

I don't think it's the temperature.  The larger tiers would be cracking first if it was just a thermostat problem.

I think that the newer fridges have extremely efficient compressors that dry out small items a lot faster than old fridges.

It looks to me like the combination of boards and your particular recipe is the problem. Your icing appears to have slightly crusted, and then a bit of pressure from the board caused it to form those crack lines. 

Since innumerable cakers use these same boards without issue, I would hazard a guess that it is your recipe that needs tweaking. Adding a bit of corn syrup might help. Edna de la Cruz suggests that in her crusting BC tutorial online. I tried it once when I still used crusting BC and I noticed a difference. Doesn't water down the consistency too much but adds some flexibility. If you do not want to mess with your recipe, I would suggest starting with more rigid boards and see what happens. It's hard to pin point exactly what the cause of the issue might be because there are too many variables. Run a little experiment, keeping all your conditions constant except one (the variable you're testing for) and go from there.