http://www.seattlefabrics.com/webbing.html...eatbelt_Webbing
I buy my 1 1/2" hardware from Classic Design Works because it is good, heavy hardware:
http://www.cdwplus.com/brassL.html
I use regular thread to sew the colorful fabric to the webbing, but I use a very strong thread to sew the collars together and sew the hardware in:
http://www.sewtrue.com/Thread.html#Anchor-%233-56210
The colorful coverings for the collars are simply good quality quilting cotton. I also use Wonder-Under and fusible interfacing, a rotary cutter, rotary cutter ruler and a rotary cutting mat.
Each collar will require a 20" length of webbing, a 12" length of webbing, two loops, one slide, and a D ring.

To make 1 1/2" wide collars, you will need to cut 2" wide strips of the colorful fabric.

In addition, you will need to cut 1 1/2" wide strips of the fusible interfacing and 1/4" wide strips of the Wonder-Under.

Grab a pair of scissors and head to the ironing board. Cut the 1 1/2" strips of fusible interfacing into 20" lengths and 12" lengths. To make a collar use one of the 20" pieces and one of the 12" pieces. Center them on the WRONG side of the 2" wide strips of colorful fabric, fusible (bumpy) side down - leave 2" between the interfacing strips. Iron the interfacing on the cotton, on the wool setting, to fuse. Cut strips apart with about 1" of fabric sticking out beyond the edges of the interfacing.
Next, place 1/4" strips of Wonder Under at the edges of the interfacing, bumpy side down, and iron on WOOL setting to fuse to back of interfacing.
Peel the paper backing from the Wonder Under:
Now turn the edge of the fabric over and fuse it to the underside of the interfacing to eliminate unfinished edges on your collars:
You are ready to sew the fabric onto the webbing. Sew close to the edges - less than 1/4 " - and always leave plenty at the ends to wrap around (3/4 - 1").

Fold the excess fabric down one time to touch the edge of the webbing:
Fold the fabric over again and sew over the edge of the webbing:
You now have a strap set, all you need to do is add the hardware and you will have a collar. It is 1:30 AM and I am beat. I will add a 2nd post tomorrow to explain how to attach the hardware that makes a strap set into a collar.







