****o this is Beth from Dremel Customer Service. We sell a circle cutter & straight edge guide, model 678-01, that will enable you to cut perfect circles from 3/4" - 12". It has a depth adjustment that will allow easy setting of the correct cutting depth. This includes the 1/8" Multipurpose cutting bit for the material you are trying to cut. If you'd like to take a view of this, please go to our website at www.dremel.com
and look under "Attachments" for the Rotary Tool. If you have any further questions, you can always feel free to call our Dremel Customer Service Department on our toll free phone number of 1-800-437-3635, Monday-Friday, 7:00 am - 6:00 pm, CST. Thanks for your question!
-Dremel Customer Service Team