You can't get straight lines with liquid mask. Instead, try 'Cheap Chocolate
Foil' as explained on my Stuka page:
http://www.sml.lr.tudelft.nl/~home/rob/models/stuka.htm
Copied from the page: "I used adhesive aluminium foil, not expensive Bare Metal
Foil, but Cheap Chocolate Foil. It could be different in other parts of the world, but in Europe, chocolate bars are usually wrapped in aluminium foil, followed by a printed paper wrapping. In many cases the aluminium foil is white on the inside, and this is the type of foil you need. This foil can be split in a thin aluminium layer and a paper layer (a fiddly job!), and the aluminium layer remains slightly tacky after the split. It is perfect for masking canopies, much better than Bare Metal Foil because of its much lower tackyness.
But for permanent foiling I wouldn't use it, I guess. I have to add that the splitting is relatively simple with some types of foil, and near impossible with others. You may have to shop around a little."
Examples are also shown on other pages of the site (Komet, Super Etendard,
YF-22). Try it - it is nearly free!
Rob de Bie
My models:
www.sml.lr.tudelft.nl/~home/rob/models.htm
Me 163B site:
www.sml.lr.tudelft.nl/~home/rob/me163.htm