Tom Martin
Well Known Member
A few pictures of finished details. Note that this is just at the primer stage. Before paint there would be one more sanding and filling stage but this is at the point where I want to fly the plane and work out any issues before final paint
https://tommartin.smugmug.com/My-First-Gallery/i-K5jVMRB
This first picture shows the left inlet of the RV14. As delivered from Van's this corner is shaped a bit the opposite of what we would like for an inlet. The outside edge points in towards the centre of the engine. This is wrong on two points. Number one it is a "converging" inlet, meaning that the air is being forced inwards rather then straight back or slight outward as you would see in a diverging duct. This is not an efficient way of converting dynamic air to static air.
Also the pinch point means that your actual opening size is restricted. This was the case on both outboard lips. I cut away the offending parts and then rebuilt them with an inner flange that keeps the two cowling parts aligned properly.
Note also the inserted cover for the end of the cowling pin. We really want the inside and outside of cowling as clean as possible.
Hopefully this will help with cooling. If the engine then tends to be a bit too cool the outlet can be closed off. Proper cooling begins with properly formed inlets.
https://tommartin.smugmug.com/My-First-Gallery/i-K5jVMRB
This first picture shows the left inlet of the RV14. As delivered from Van's this corner is shaped a bit the opposite of what we would like for an inlet. The outside edge points in towards the centre of the engine. This is wrong on two points. Number one it is a "converging" inlet, meaning that the air is being forced inwards rather then straight back or slight outward as you would see in a diverging duct. This is not an efficient way of converting dynamic air to static air.
Also the pinch point means that your actual opening size is restricted. This was the case on both outboard lips. I cut away the offending parts and then rebuilt them with an inner flange that keeps the two cowling parts aligned properly.
Note also the inserted cover for the end of the cowling pin. We really want the inside and outside of cowling as clean as possible.
Hopefully this will help with cooling. If the engine then tends to be a bit too cool the outlet can be closed off. Proper cooling begins with properly formed inlets.
