I originally got the idea for a shortened crest block from a picture by Peroni. The block was cut from two 3/4 inch pieces of red oak glued together. I used a jigsaw to cut the block.
I drilled 1/4 inch holes with distances as prescribed by Matt in Legio XX's site, except, instead of using a 1/4 inch drill, I used a 1/4 inch forsting bit.
The block was painted red, and then the tie downs were attached using brass nails.
I cut the horsehair from a 27 inch bundle, into 9 inch lengths.
Then I made tufts of about 1/8th inch diameter, and double knotted them using brown linen thread. (snip the thread ends close to the knot!)
I put the middle row in first, putting two drops of Elmer's Wood glue in each hole.
The one inch tall crest holder was made by Dean Cunningham.
I'll trim it down to about 3.5 inches later. My advice is to make the tufts one at a time, and glue them in as you go. You get a much better feel for an average diameter that way IMHO.