I used a buttercream recipe Jennifer Dontz shared with me. It uses Crisco and Sweetex. With Creamer mixture. I wanted this to barely crust. So I used a little more fat and creamer. I am slow icing my cakes. I did use the quick icer tip. IT started crusting on me real soon. As hard as I try my cakes come out with a terrible cing job by the time I finish it and it gets handles. I follow sugarshacks method. Tank goodness pictures hide all the flaws. I do this as a hobby and I want to keep improving. I have done this a long time so I am discouraged. Any suggestions? I wish I could take a class from Sharon. Another thing I am going to go back to icing my cakes frozen. Just to hard to handle when they are not. The 16 in. was torture.
It sounds like you need to use a recipe with a higher fat to sugar ratio to delay crusting. You can add a little bit more Crisco or Sweetex to your current recipe and see how that works. I wouldn't add more liquid because that may change the consistency of your icing too much. If you want an icing that "barely crusts" then you should try the Whipped Cream buttercream recipe under the most saved recipes or try one of the meringue buttercreams. The only issue is that you can't use the paper towel method on it.
Do you own a bench scraper? That gets the sides smooth relatively fast for me. If you do the whole Viva paper towel thing you can use that to smooth any spatula marks after it crusts over.
Love your name-I have two Bostons myself-irritating me now as I type.
I use the buttercream dream recipe off of this site and I really like it because while I am using it, it does not crust, but if I pop it in the fridge for 5-10 minutes it crusts just perfectly enough for me to do one final smoothing on it.
I second the advise of getting a bench scraper. You can wiz around a cake quickly. I am not fast, but unless a fan is on it I have time to get it smooth before it crusts.