Curving small flanges for braces on slide tubes, etc.

[arpthark]

I have some smaller mandrels and round steel that works well for forming medium-to-large sized flanges, but I have a few little pull knobs, small braces, and things like that which have small flanges that I would like to get to seat perfectly on rounded slide tubing. I'm having a hard time getting them to behave in a way that doesn't involve accidentally mashing my fingers a few times. Do you have a method for fiddly parts like this?

[MiBrassFS]

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