I bought some pearl core braid , distributed by Hareline Dubbing, but have no idea how to use it. It is basically some flash tinsel braided into a rope. Do you have any ideas how to use it?
Sounds like you mean mylar tubing that has a core. You can use it for body material. Here are a couple of ideas:
It is commonly used for bodies on streamer patterns. You cut a section to length and remove the core material. The braided tube is placed over the hook and tied down at the tail end, the frayed ends of the tube make a nice tail. Push on the tube to compress it a bit and tie off athe hook eye. You should get a hollow tube with the hook shaft at the center.
Here is a nice example of the material in use…
http://www.charliesflyboxinc.com/flybox/detail.cfm
The kind I get is used for caddis “Poopah” bodies, and San Juan worms.
Thanks for the replies. maybe i wasn’t clear on the material. http://www.lakelandflytying.com/1675/Body/Pearl_Core_Braid.aspx
Ken Y I did a google “Pearl Core Braid fly pattern” and one that came up was from Feathercraft showing the braid tied in at the eye of the hook across the length and tied in at the bend with a short trailer tail. If the core is removable this same type is used in “Snake Fly” in England. Google "Snake Fly"BILL
I use that in red for some ‘san juan worms’ They work okay.
I also used some chartreuse for crappie cany bodies. they look great, but I have yet to use them.
I love the extra sparkle, but it might catch me more than the fish. 
Like herefishy, I’ve used it for a variant of Fox’s Poopah locally referred to as the “Mangy Pooper” (good steelhead fly) and for San Juan worm variants.
The material does not taper nicely in a flame like regular vernille, because the two materials burn a different temperatures. You can get a fair taper with a soldering iron, but I sort of gave up using the material because it wasn’t as easy to work with. Does any one know how to get a decent taper with this stuff?
One tier I know uses the pearl core braid as the body of a pretty effective alevin pattern. Abdomen like a Fox’s Poopah with an egg sack of globug yarn at the throax and bead chain eyes.
I’ve not seen any other patterns using this product.
I was just thinking about how to taper this stuff, and wonder if you pulled the outer layer back and lit the inner layer with a lighter, then could you pull the outer layer back and melt it?
Tried that. Still couldn’t get anywhere near as smooth a taper as I’ve seen on the commercial ties of the Mangy Pooper. I know it is something simple, but just haven’t been able to figure out how they do it.