This book arrived yesterday and it has a lot of good information in it. So for example Bilger suggests making a crank for advancing the minute wheel to save wear and tear on the minute hand. In the picture, the round brass piece is part of the hardware for holding on the minute hand and has a square hole that goes on the end of the minute tube. I made the crank on the left in less than fifteen minutes from a piece of metal in my junk box. I drilled a 3/32" hole, then squared it off using a small file. Also he suggests using unbent paper clips as temporary hooks for holding the weights onto the chains. That is blindingly obvious, but I hadn't thought of it and had laboriously bent and unbent chain links to take the weight hooks on and off several times. One quibble I have is that he exaggerates how difficult it is to adjust the gong. On page 80 he says that if there isn't an inspection hole in the back board, "it is almost impossible to adjust a misaligned hammer. You are working virtually blind and any adjustment would just be a hit and miss proposition." He goes on to suggest cutting a piece of Plexiglass to the size of the back board and mounting the gong to the Plexiglass. That is way too much trouble. I've watched a YouTube video in which a guy makes pencil marks on a toothpick to measure how far the horizontal part of the gong is from the back board and then makes another mark to allow for the thickness of the back board and then puts a straight edge across the back of the case to measure how far the hammer needs to be moved. Also with the bellows out you can shine a light up through the pendulum opening and look in through the holes in the side of the case for the whistles to see what is going on.
You can get close with a small ruler. Measure where the straight part of the gong is from the bottom of the back plate. Then measure where the hammer is from the bottom of the case. The hammer needs to be a tad higher. Once you get that, the rest is a forward or backward adjustment.
