To make a piper's plaid you need a length of double width tartan, ie, tartan that has been woven approximately 58" wide (149cm) with a selvedge down both sides. The length needs to be approximately 3.6 metres (4yds). It can be 13oz or 16oz in weight. I personally prefer 13oz. It's lighter, less bulky and more comfortable to wear but you need to be aware that with most tartans the size of the sett will be slightly smaller than the sett on the kilt if the kilt is made in 16oz weight.
In this example I am working on a MacKenzie tartan. With other tartans some of the measurements will vary according to the size of the sett.
All measurements in these two diagrams above are in centimeters. They are only a guide. They will vary according to the tartan you're working with and the size of the person you are making the plaid for. The top diagram shows the front of the plaid with the pleats pointing downwards. The bottom diagram shows the other side of the plaid where both selvedges overlap to cover all the pleating at the back. The full length of the plaid is pinned down in this pattern and the pleats steam-ironed in.
The yellow lines show the lines of stitching on both sides of the plaid. The lines of stitching on the top side should be just to the side of the light stripes in the tartan.
Making the Fringes
Making the fringes is by far the most time-consuming part of the job. It requires a lot of patience but the end result is well worth the effort.
Stage 1: Tease out the horizontal threads to a depth of about 5". This isn't easy at first until you work out for yourself the best technique to use. I find I can pull out two or three threads at a time, wrking from the middle and working out the selvedge at either end.
Stage 2: To make each tassle I take one group of threads ranging from 6 to 8 threads. I twist it in one direction (I'm left-handed so I always twist it anti-clockwise). I then hold that twisted section between my 3rd and 4th finger while I twist a 2nd section of about 6 to 8 threads in the same direction. Then I hold the two sections together and twist them back in the opposite direction and tie them together with a tight little knot as close to the end of the tassle as possible. This pictures below still show how I used to do it using a smear of glue instead of a knot to secure the tassle. I do now prefer to use a knot.
I then coat the end of the tassel with a ligh glue and rub it between my fingers to matt the fibres together and prevent the tassel unravelling. Since taking these pictures I prefer now to tie a very small tight knot at the end of the tassle instead.
Twisting each fringe.
Pleating
Working across the material from selvedge to selvedge, pleat the material in such a way that each pleat is approximately 1cm to 0.5cm apart. Just as with a kilt, you can either follow "sett pleating" where you maintain the pattern of the tartan or follow "military pleating" where you show the same part of the sett in the visible section of each pleat, ideally a light stripe. What you're aiming at is an overall width of about 15cm (6") with about half of this being pleats.
On this MacKenzie plaid, each pleat is going to have a white stripe right on the edge. There are 12 stripes in the width of this tartan so I'm making it with 10 pleats, allowing about 4" on either end to cover the back of the plaid. The pleated section is going to be about 3" (75mm) wide so each pleat needs to be 3/10" 7.5mm) apart.
Turn the plaid over and overlap the two selvedges to cover the underside of the pleats. The overall width of the plaid is 6" (15cm).
Looking again at the front of the plaid, the pleated section covers half the width of the plaid.