Protection of wings from engine heat

[Bruce Hughes]

The RAF manual requires thin aluminum shields
at the end of the wings to protect the wings from
engine heat.   However some builders have gone to
stainless steel.   I am at the point of needing to
order the steel.  

ASC lists 304 stainless, .018 inch thick.  
I assume that that size will be OK

A piece 12" X 48" could be cut in half for
shipping and should be large enough to do the
job, I think.

ASC also lists 302/304, Ann. at 035 inches thick.
Would that thickness be required?  The aluminum
specified in the RAF manual is thinner than that.
What is the Ann.?   Annealed?   Necessary?

Thank you for any comments.
 

[EZPILOT742X]

Like James Redmon did on his Berkut, I used Thermo-Tec Aluminized heat barrier with adhesive backing. It's as simple as cutting out the pieces, sticking them on the wing, and filling in the seams with some red high-temp RTV. The material is about .010 thick and is supposed to be good for a couple thousand degrees. It took me about half an hour to do it all. ACS sells this stuff but you can also find it at auto parts stores and suppliers. It's a little pricey.. you'll probably spend $50 between the thermo-tec and the silicone, but it makes for a very quick and easy job that looks great. It was very clever of James to come up with this... Good Work :-).

Chris Randall
Berk-EZ N742X
KWHP, CA

[Bruce Hughes]

Thanks for your reply Chris.   The Thermo-Tec idea sounds good but I
have SS on hand and today I will be cutting a shield.   I cut one
yesterday.

During cutting I realized a few facts:

1. If I follow Burt's original design in aluminum, I will have a pretty
   heavy shield.   Omitting the tabs should be possible.   That should
   reduce the weight by about 25 to 30 %.

2. The cowling fits the wing tightly right now.   The tabs would be have
   to forced into that nonexistant space, between a curved wing and a
   curved cowling.

   There is NO way that is going to work well.  Aluminum is soft
   enough to possibly force fit it but that will not work with stainless.

3. I really do not have a good way to bend all of those tabs.   I
   CAN bend the one at the base because it is only 7 1/2" long
   SS is a lot harder to bend

4. I have a good way to attach the heat shield to the wing - really
   better than the tabs, I think.

Thanks for any comments.