when design or work with modeling, edge blend operation is important, for plastic part, or casting part with edge bled machining process of your mold will more easy, becouse all CNC cutter machine always have radius.
Click your scroll button is same with click Apply Button
Step1
edge blend
Ok, first time to begin edge blend operation is click the edge blend icon, or you can use file menu, for menu click insert, detail feature and choose edge blend
Step2
edge blend window will appear, at this window fill the blend radius that you want, the range that accept is very depend with your model length, when it doesn't accepted, warning box will appear " that your radius is to large"
Step3
click the edge, then click apply button, change your radius then click the edge again. click OK button when finished