|
|
|
|
Justin Shumaker's Kitlog
|
Date: 2-2-2014
|
Number of Hours: 20.00
|
Manual Reference:
|
Brief Description: Header Tank Design
|
|
I had a rough time getting this head tank designed and mounted inside the aircraft. It was an uphill battle the whole way. Ultimately I decided to use a 1 gallon Nalgene FLPE (Fluorinated), which is highly resistant to aromatic hydrocarbons. The container was about $50 and is 6 inches in diameter. The idea was to have (2) AN-6 bulkhead fittings stick through the bottom, one for the engine to draw fuel and another to transfer fuel from the wing tanks into the header tank. If air bubbles developed in the transfer line then they would not affect the gas turbine pump. Rather than have the pilot manually flip the transfer pump switch every time the tank is low (i.e. every 3-4 minutes), I decided to use a float switch (rated for diesel) and some electronics (to create hysteresis) to keep the header tank topped off automagically. The switch was only $13 from Zoro. Not really thinking about how this would all come together I just started purchasing stuff and had a general idea of what the finished result would look like.
The first major obstacle was getting the aluminum nuts and teflon washers onto the bulkhead fittings on the inside of the tank. This took some thinking. Ultimately I almost gave up and started welding a header tank, which turned out to be too big, hence the 20 hours on this project (2 hours wasted). So, back to the nalgene bottle. It occured to me that if I could weld a couple pieces of aluminum onto the edges of the nuts I could get them tight. Two wrenches and a tight grip on the bottle and the nuts were on tight with teflon washers. As the nuts spin these metal pieces push into one another resisting the turn of the wrench, thus tightening the bulkhead fitting. The Nalgene bottle had to be sanded smooth with my orbital sander. The bottle is 1/8" thick, so no concern over it getting too thin. Only 1/32" of material was removed, namely the lettering and logo branded onto the bottom during the molding process.
|
|
Placing PTFE Washer on Bulkhead Fittings
|
|
Custom Washers, Aluminum Tig Welded
|
|
The Finished Mounting System
|
|
|
|
|
|
|
|
|
Copyright © 2001-2024 Matronics. All Rights Reserved.
|
