What is flate?

A flate is not a commonly known term in English. It is possible that you may have intended to refer to "flate quilting," which is a machine quilting technique that creates a flat surface on a quilt using a longarm quilting machine. Alternatively, you may have meant "flate" as a misspelling of the word "flatey," which is a Scottish island in the Shetland archipelago. More information is required to provide an accurate answer.