Things are moving forward with the headrest.
As you'll see below I've made up a bracket for the Dzus quick release fastener and bonded it to the back of the cockpit area.
For those of you wondering why I didn't do this before painting the cockpit - it's called impatience :)
I’ve also got around to fixing the engine mount hole that was out (by about 6mm). I just filled in the old hole with flock then thought it would be an easy case of drilling a new hole. But as usual, nothing is easy! The drill was tending to migrate towards the flock as that is a softer material than the carbon. This would have elongated the hole in the flock area - no good. So I ending up using the Dremel and about 1.5 hours later had a hole that was perfect.
With that done it was time to start on protecting the firewall. For me the best material for this is Fibrefrax. It is very easy to work with - just cut with scissors and glue with a very high temp glue. No-one would import the glue made by Fibrefrax from the USA because it is deemed too dangerous. I found a glue used to repair fireplaces and exhausts - which is good for 1200 degrees C. The Fibrefrax is good for 1300 degrees C. Easily exceeding the FAA requirements of 1100 degrees C. A sheet of stainless steel would do the same job but would be very difficult to shape around the edges. Also the outside of the fuselage that will sit below the cowling needs protecting too. I will do this with the thinner 1/16th Fibrefrax and cover that with Ali 'Cool-it' tape.
After all this is done then I will cover the lot with a heat blanket (shown below) which is fibreglass on one side and ali on the other. This is purely for cosmetic and practical reasons as the fibrefrax would easily get dirty and soak up oil or other fluids.
I've got the 1/16th Fibrefrax on order so I'll probably get on with the battery and finish up the headrest next.
Bracket for headrest with Dzus fastener and spring back shown for position. |
Spring riveted to back of bracket |
Ditto |
Figuring out where to put the bracket |
Engine mount with top right hole not done. |
1.5 hours later with hole all done. |
Blue tape shows how far back cowling will go. |
Heat blanket that will go over the Fibrefrax - backside shown on the left |
Fibrefrax. |
Very high temp glue - good for 1200 degrees C. |
Gluing on the Fibrefrax. |
Headrest bracket bonded in with flock and 2 layers of carbon. |