What issues have you ran into using tiller block to determine the center of the limbs?
you mean the method recently posted about putting 2 dowels through your gizmo ?
You only have a chance of it working if the stave was spit. Forget it if the stave was band sawed. The best way is to get a pencil and a magnifying glass if you need it and pencil in the lateral or vertical grain. Here check it out.
http://georgeandjoni.home.comcast.net/~georgeandjoni/osage.html
Jawge
Actually I was referring to the tillering blocks used to determine center line of the limb on glass backed bows. I have seen where they have been made out of washers and was just wondering how well they work.
Tiller blocks work very well, I wouldn't be without a set. I made mine from an aluminum bar, but I have seen them made from washers. They do require that the end of the limb be square, and they won't work with thick antler or horn overlays. I glue on a 1/16" phenolic overlay then use the tiller blocks to find center. After sanding the limbs to width I glue on the rest of the overlay. The only problem I've had with them is my first string wasn't strong enough and broke, it dented the limb and threw the tiller blocks across the shop. I actually found one block inside the drum sander.