I'm thinking of hand painting the Iron-cross on my latest German build. I plan to use tape to get a proper outline for the cross. Will this have the desired effect? And will the tape damage the enamel paint upon removal?

Thanks in advance!

If you mean not using an airbrush, I am not sure you will get a better result than using a decal...

If you use modeller's masking tape like Tamiya it should not affect the paint below,for any other it is better to try before using it. Sticking it a couple of times to other surface will weaken the adhesion if needed.

Anyway there are other options depending on your budget and skills, like dry transfers, photo etch templates or even I have tried my own template cutting the shape from a sheet of transparent plastic (the one used to print presentations on).

What period of German AFV is this for? If it's a Zimmerit coated tank forget about masking. Most of the markings I've seen on these vehicles are roughly hand painted (in the case of HJ, very roughly!). If an earlier grey painted vehicle, what the others said.