Chimney base shape? How to cut an arch in firebrick

Hi! I’ve seen a lot of pictures of chimneys where the base round of firebricks is trimmed to fit the arch so that it’s like “parabolic” for lack of a better term. Anyone have an easy way to cut that shape? Alternately I can shape the base with just mortar but I thought it would be better to cut the bricks to fit. Thanks!

Hi Hahvahd and welcome to the BrickWood forum.

Would you mind sharing in a reply a couple of the pictures you’ve seen? I think that would give our experts here a much better idea of what you have in mind.