patchitpat

Hi I'm new here so I don't know if this subject has been gone over before or not. I have a Brother Duetta embroidey machine and would love to make a crazy quilt with it. I have many designs but the trouble is a lot of the designs I have come in a variety of sizes. Can I sew different sized blocks together to make a large square, say a 20" block? Or would it be too bulky and just awful looking?
Thanks for your help in advance, I'll make sure to check back often.
Pat