Hi Mike,
Yes I forgot to mention that. Last time I used this system I used a cople of layers of tape that is like servo tape only not as sticky. This held the mask well back from the edge. Playdough is an excellent idea although it could create protests from your kids.

. I can imagine what would happen if they appeal to higher authority, "Honey, what have I told you about taking the kids toys? Now go play with your own"

Good Luck
John.
ORIGINAL: I-NAV
John,
Happy New Year to you and the Gypos. I tried that but the tape used to hold the card down leaves gaps in the overspray. Might have to try something like putty around the radius of the mask so there are no gaps. Been looking at my kids Playdough pumping station
Mike