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Offset Sine patterns: amplitude vs spacing


At the OTI symposium I was cutting some guilloche patterns and I talked with a few people about the trade-off of spacing versus amplitude for offset sine wave patterns. I decided to write out my way of calculating the offset (for a given amplitude) or calculating the amplitude (for a desired cut spacing). See the attached pdf file with the math. Also attached are xls spreadsheets so that you don't have to worry about the math. For Mac users, there is a .dmg disk image that can be used with Apple's "Numbers" spreadsheet.


Last edited:

Frank Dorion

New Member
Thanks, Bill for your continuing generosity in sharing your OT knowledge. For those of us for whom OT still holds many mysteries, information such as your guilloche math is invaluable and very much appreciated.