Hello guys and gals, I have had quite a few PM's about making stretching boards and just wanted to put a little how to together and show people just how easy it is.
This is how to make each side perfectly symmetrical to the other.
Tools needed:
Jig saw
Belt sander
You will need a router with a flush trim bit and a 1/4" round over bit for making the stretching boards after you get your template made. But I'm not going to get into that right now.
This is a template for a large Coyote, but will apply to all.

The first thing you will do is cut your board to the correct length, and draw a line right down the center of it

You will need the correct dimensions on where to make your marks.

Next start making marks the correct measurement down and I always put the width that they need to be.

Next take a square and draw a 90 degree line across your mark measuring down the board.

Next take your width measurement and cut them in half and measure on your 90 degree marks from the center line and make a mark.

Now you want to try to connect all your lines while keeping a nice and smooth taper with no abrupt dips or humps.


Mark all laid out ready for cutting.

Board rough cut out and ready for a belt sander.

You might not need a helper, but I prefer to have one, she helped me clamp the wood on the side of my table saw for the belt sanding.

I use an old school belt sander that weights a ton, 80 grit papers works well for removing material fast.

You can clearly see the line here, I try and sand until you just make the line disappear.

All sanded nice and smooth.
Now for the tricky part, making the uncut side exactly the same as the other side. I have a big long roll of paper that we got from the school. They were going to throw it out, so we grabbed it, but you can just tape a bunch of pieces together.

Take the piece of paper and tape it right down your center line.

Rough cut your paper so its not flopping everywhere.

Take your piece of wood with the paper tapped onto it and flip it over and lay it on something flat.(I just used my floor)
Draw a line on your paper with the sharpest pencil you can find.

Now you have a template of the other side that is an exact match.

You want to take a pair of scissors and just cut your pencil mark off, this should leave you with a nice clean edge.

You will want to tape your template down so it doesn't move on you, this picture doesn't show it tapped but you get the idea.

With your template tapped down you want to draw a line right on the edge of your paper template.