Square to Round Developer

Gellis apps

About this app

As a fabricator of 40+ years, the last 30 or so as the workshop manager, I have constantly used trigonometry etc. to calculate cones, segmental bends and much more. Nowadays I am constantly asked by the fabricators to calculate developed lengths etc. to save them the time and effort of laying it out. I have developed this app so that they can do it for themselves and therefore save “MY TIME”.


With this app you can quickly and easily develop patterns for square to rounds, rectangle to rounds, rounds to squares and round to rectangles. Simply choose the type of square to round you wish to develop, enter the required outside dimensions and material thickness then press develop. The developed pattern can then be marked onto the plate ready for cutting and shaping. Instructions on how to mark out completely by hand and how to mark developed pattern onto plate are included.

I hope that from your feedback/comments I will be able to add extra relevant features and amendments in future editions.