Elbow Rests & Fuel Valve

3/14/2010

I am currently trying to ensure that I get on all the welded tabs and brackets that need to be done for painting of the fuselage. This is certainly a long road! So, I have been installing lots of existing stuff so I can look for potential clashes every time I add tabs for new additions. Example: Running fuel lines and their respective connection tabs have to live with other stuff like pushrods, and rudder cables etc. This got me started on looking at the fuel system on the cold side of the firewall. I decided on an Allen valve. Strangely, the day I was going to buy it from ACS, I was talking to an IA friend who by chance, had a used one on the shelf...he needed a hand for an hour, so the valve was my compensation.

The valve is a three way [designed for 2 tanks], but I am almost certainly going to use it as a simple isolation on-off valve. I really like the positive click of the valve action and its reasonably low resistance when operating - which will lend itself to being a smooth operating deal once I attach the extension tube to it. This extension tube will run back to the rear cockpit. I managed to locate the valve on the outside of the fuselage, I like this set up, since it eliminates any PAX interference. I created a steel box with folded sides [first attempt was successful!] and welded it in place. The operating extension tubes are usually made from 4130 tube, but I am looking at aluminium with a thicker wall and half the weight to do the same job, the fastening method would be rivets instead of welding.

While sitting in the rear cockpit, I realized I had nowhere to rest my elbow in order to comfortably operate the throttle quadrant, so I decided to design an elbow rest. I was going to have just the one, but it looked odd on its own, so, a pair it was. The rests needed to be solid, but of course light. So they were made from 6061-T6 0.50 (nasty to bend!), the stiffeners were 0.032, and there is a central gusset in the middle. This gusset made a huge difference regarding flexing. I planned on perhaps, a bit of foam on these rests, along with some leatherette that will match the headrest and seat back panel, but they seem comfortable as-is... time will tell. The rests are really the only creature comfort in the cockpit, since everything else is planned to be bare..no wall linings, no floor boards etc. The picture shows the rests just after running a fine sanding board over them...[they looked much better before :0| ] I did the sanding so I could identify the low spots for fill and paint.