The modification to Anthony’s scope was simple really. The materials use were Stardust Formica which I got it at Nover & Co Pty Ltd, 93 Munibung Rd, Cardiff, NSW, Ph (02) 49566619 and 2mm Virgin Etched Teflon address: Cadillac Plastics Australia, 7 Aminya Place, Cardiff NSW Ph (02) 49545455.
The first four photos show the Formica already stuck to the base. In our eagerness to start we forgot to take some pics to show how the Formica was glued to the base. I used contact cement and applied it evenly to both sides, let the glue go off for a couple of minutes and bring both surfaces together. (Great bond!) The Formica was cut 5mm oversized so after gluing we cut the excess around the edge with a pair scissors then filed it flat and sanded it smooth.
Window 2 shows the filing, sanding and drilling of the centre hole.
Window 3 shows the drilling and positioning of the centre pin. The hole in the Formica should be slightly larger than the hole in the base and the pin should be tapped in far enough to be flush with the (top) of the base.
The last four pics show the ground board. It was quite a job removing those furniture sliders (or whatever they’re called) that Anthony had previously but we managed. I cut four 35mm squares of Teflon (the size actually depends on the weight of the telescope) and then all sides were bevelled with the file. A hole was drilled slightly larger than the ground board on one of the squares and it was glued in the centre with the other three being glued 1mm or 2mm from the edge. The squares were orientated in such a way that the point of the square was facing towards the edge of the ground board.
Anthony, from memory I think that we tightened the centre bolt a bit to much it might be advisable to loosen it maybe half a turn, the base of the telescope should just sit on top of the ground board and the bolt is there so that the ground board doesn’t come away from the base.
A quick simple fix that all the gs dobs could use.
