I have modified this one so that the saw cannot be rotated, when you are sawing pancake dies the angle of cut through the die has to be kept consistent, the die is rotated and the saw kept straight.
This is a jig I use on my bench pin every day, it means that all cuts are at 90 deg to the metal you are sawing, saves a lot of time and trouble when you come to filing up the edges. If you look closely at the first photo there is a line on the pin which is at a right angle to the sawblade.
Ever had trouble fitting a piece of inlay into a contrasting sheet of metal? Look at the photos below,
these were a sheet of brass and a sheet of copper glued together, then cut at an angle, it can take a little experimenting to get the correct angle, but the cut out piece from one sheet will fit exactly into the body of the other sheet. If you look closely you can see the drill hole in a corner, drilling this at an angle would have been better!
This only works one way, this is what you get with the remaining pieces. Remember to work out which colour is the body and which the insert!