The last system to be installed on the panel was the vacuum system for the Attitude indicator (AI) and direction indicator (DI). The system is completely conventional. The vacuum pump on the engine pulls air through the regulator mounted on the firewall which maintains a 5PSI pressure differential. The regulator has two inlets, one is connected to the VAC terminal on the AI and one to the VAC terminal on the DI (blue pipes). The AIR terminal on the DI is then connected directly to one of the outlets on the air filter. The other outlet on the air filter is connected both to the AIR terminal on the AI and also via a "T" connector to the AIR terminal on the vacuum gauge. The VAC terminal on the gauge is connected to the GAUGE terminal on the AI. The GAUGE terminal on the DI is blocked off. In this way the gauge measures precisely the pressure drop across the AI. So in summary the vacuum pump sucks air from the air filter via the AI and DI.
Up until today I've had a catch 22 which needed solving. The tank had to be installed before the coaming in order to complete the routing of all the cables, pipes, and tubes from the panel. However, the coaming had to be installed before the tank in order to get the tank neck through the hole in the coaming. The solution was to cut out a small section of the coaming around the fuel tank. The sides of this piece were then riveted to three strips of aluminium to act as support for the rest of the coaming. These were match drilled to the coaming and nutplates installed on the underside. This small section could then be screwed into position on the firewall together with the formed piece of aluminium which closes the gap to the lower edge of the windscreen. The remainder of the coaming was then slotted into position. The two formed strips which support the side windows were then inserted and the coaming screwed into place. Next all the screws that connect the panel to the combing and fuselage cross member were installed. Finally, a piece of glue lined edging strip was heatshrunk into place round the lip of the coaming to protect the edge and/or the pilot! So that is the panel absolutely complete and installed. Hopefully it won't need to come out again. The coaming is removable in case of future problems but in service this will also require removal of the windscreen - not difficult but a bit tedious. I'm very pleased with the way this has turned out. I wanted something in keeping with the type of aircraft but fully functional and ergonomically laid out - I think I have achieved this.
The last system to be installed on the panel was the vacuum system for the Attitude indicator (AI) and direction indicator (DI). The system is completely conventional. The vacuum pump on the engine pulls air through the regulator mounted on the firewall which maintains a 5PSI pressure differential. The regulator has two inlets, one is connected to the VAC terminal on the AI and one to the VAC terminal on the DI (blue pipes). The AIR terminal on the DI is then connected directly to one of the outlets on the air filter. The other outlet on the air filter is connected both to the AIR terminal on the AI and also via a "T" connector to the AIR terminal on the vacuum gauge. The VAC terminal on the gauge is connected to the GAUGE terminal on the AI. The GAUGE terminal on the DI is blocked off. In this way the gauge measures precisely the pressure drop across the AI. So in summary the vacuum pump sucks air from the air filter via the AI and DI. 
Up until today I've had a catch 22 which needed solving. The tank had to be installed before the coaming in order to complete the routing of all the cables, pipes, and tubes from the panel. However, the coaming had to be installed before the tank in order to get the tank neck through the hole in the coaming. The solution was to cut out a small section of the coaming around the fuel tank. The sides of this piece were then riveted to three strips of aluminium to act as support for the rest of the coaming. These were match drilled to the coaming and nutplates installed on the underside. This small section could then be screwed into position on the firewall together with the formed piece of aluminium which closes the gap to the lower edge of the windscreen. The remainder of the coaming was then slotted into position. The two formed strips which support the side windows were then inserted and the coaming screwed into place. Next all the screws that connect the panel to the combing and fuselage cross member were installed. Finally, a piece of glue lined edging strip was heatshrunk into place round the lip of the coaming to protect the edge and/or the pilot! So that is the panel absolutely complete and installed. Hopefully it won't need to come out again. The coaming is removable in case of future problems but in service this will also require removal of the windscreen - not difficult but a bit tedious. I'm very pleased with the way this has turned out. I wanted something in keeping with the type of aircraft but fully functional and ergonomically laid out - I think I have achieved this.
