One thing about slip wings is that if you look at the quill feathers, you will notice how near the stem the fibres are quite thick, then there is a ridge where the fibres become thin. This is very easy to see when you cut your slip and look edge on to the slip. When you tie in the wings you do not want any of the thick bits on the fly. The Outer primaries tend to have a lot of the thick stuff and a lower proportion of the usable fibre. Also, when you get into marrying different colours, make sure you marry fibres from a left feather to a left feather, and right with right (you can tell by which side the stem tends to be since the leading edge, with the biots, is smaller than the other side). Good quality feathers are not difficult to marry, poor feathers are best not left in the same room together.
- Jeff