Hey Guys,

Thanks for your replies.
@Jay: I attached two images in the message where I thanked you that showed the problem much more clear. Maybe I did something wrong? Im new to the forum

Im gonna attach two new ones in this one. Please tell me if you can see them.

The first screenshot shows the dragrect used to make a (ridiculously) large vein on the front of the forearm.
The second one shows the same vein but pushed inside (as if you're using zsub) the model on the backside of his forearm.
The problem is that the vein in the second screenshot appeared by creating the one in the first.

Backface masking did not fix the problem, sadly.

Thanks again.

Jan