# How to adjust Delta Radius?

So I have a HE3D K280 printer and I am nearly done calibrating but I noticed that whenever I move 20-30mm from the center, the hotend curves downward like a dome. I've found a possible solution here where

"

- correct for bowl/dome shape by adjusting the DELTA_RADIUS parameter

and "DELTA_RADIUS increase for dome shape and decrease for bowl shape. The center (0,0) height will remain the same and the height at the outer positions will increase/decrease" .

Problem is, whenever I go to EEPROM settings, I see "Delta_radius A(0). Delta_radius B(0) Delta_radius C(0)".

How would I fix this problem?

## Comments

You might also change diagonal length. The dome/bump you describe comes from ratio diagonal length/horizontal radius. Diagonal has also the influence to change xy size so if geometry is too big/small you need to change the diagonal. On the other side diagonal is quite easy to measure so normally that is the known value and horizontal radius is unknown.