fabricflyer
Well Known Member
What are you guys using out there (if anything) for inside firewall insulation? Has anyone used, or familiar with, Koolmat heat barrier?
Thanks Allen
Thanks Allen
With all the things connected to motor side of firewall I went with double sided insulated foil on inside and worked out great. Always clean but a stand on your head to install. Aircraft Spruce p/n 09-06015 and high temp RTV and your set.
I see Proseal used between the skin and firewall flange. Why?
I see Proseal used between the skin and firewall flange. Why?
Right on the foil. Just wondering if it would be easier to clean and maintain if it was a sheet.
here how I did last year after read tons of threads , finally I followed the Dan way.
Thanks Dan
Weight would be the primary reason to use foil with its primary purpose, based on DanH posts, is to hold the fiberfrax in place so it can do its job insulating. If weight were not a concern, thicker should, in theory, be better.
Dan H sorry it took so long to get back to material I used.
Insulation with Double sided foil. Spruce #09-066016
The Insulator is one of the finest sound proofing and thermal insulation materials available, and will last the life of the aircraft.
Technically speaking, the stainless foil is a gas-tight reflector over an insulator, and as such, it cannot be replaced with something like cork. It just happens to hold the insulator in place in this application.
Choice of thickness revolves around weight and appearance. Pick what you like. As noted previously, it can be very thin and meet the fire performance requirement, but thinner is less durable and looks a bit more wrinkly.
I was thinking of replacing the fiber blanket with the cork, then a stainless sheet so,the cork was sandwiched between.
Dan H sorry it took so long to get back to material I used. Insulation with Double sided foil. Spruce #09-066016
Thanks Dan. I did a mapp gas torch test and the thermal transfer was very low, but there was lots of smoke. The cork did char and was easily broken apart but you could touch it with the torch on the other side.
The burner has been running several minutes. The black radiant heat target represents the soles of your shoes:
Jim,
Some years ago I was working a mid-engine design project with a friend. Since the main spar passed through the engine bay, we got curious about fire protection. I did the reading, built a burn test rig, etc. Later, when building my RV-8, I threw together another burn rig and started exploring how to insulate a conventional sheet metal firewall.
Just a little later, a VAF reader asked what sort of glue to use to attach a particular firewall insulation in his project. Read the ensuing conversations here:
http://www.vansairforce.com/community/showthread.php?t=37012
Turned out the very popular "firewall insulation" was actually polyester fiber. The vendor had done no due diligence before selling the stuff to builders.
A great many products being offered as firewall insulation are entirely unsuitable for a cockpit-side application. Given a typical fuel-fed fire, they will not protect the occupants, but rather, will contribute to their injury. Placing plastic, rubber, paint, or flammable fibers in contact with a red hot firewall is an invitation to the Darwin Awards.
The ironic fact is this: In the end, after much test and measurement, and by a large margin, no cockpit-side insulation scheme was as effective as insulating the entire firewall structure from the engine side...and practically nothing a builder can do to the engine side can cause injury. The above applies to both comfort insulation as well as fire protection insulation.
What do I suggest? I've posted specifics previously. Best to use the search function, because there is much to learn.
As for "Too late to insulate the engine side", well, would it be too late to install a skipped bolt, or a missed rivet, or update your panel later, or pull a tank to fix a leak? Anything worth doing is worth doing right...and you might be interested to know I pulled my own engine and mount off the firewall, as a unit, to install my own insulation. The test results were that significant.
I ended up getting an automotive heat reflecting material (adhesive-backed fiberglass with an aluminum reflective coating. I put this on the engine side of the firewall and it works quite well..This approach does not provide the flame protection that Dan's method does, but it was much easier to source and install.
Just another data point. I used the firewall 2000 material you have purchased. I did not rivet anything at all. The material is being held in place by the various components that are bolted to the firewall. It is sandwiched in between the component and the firewall. Then I have used aluminum tape on all of the edges. It has been flying for 5 years and still doing just fine.Thanks Dan,
I broke down and bought a roll of firewall 2000 from aircraft spruce Saturday for the firewall side. I'll have to pull the engine and mount but this would be for a good cause. Not sure whether to attach with a stainless pop rivet and washer or use some of that firewall 2000 rtv stuff in blobs between blanket and firewall. This blanket has alum on one side, stainless on the other, and ceramic sandwiched in between. I don't want the blanket coming off years from now and was wondering what kind of pop rivet spacing you think would do the trick?
cj
...bought a roll of firewall 2000 from aircraft spruce Saturday for the firewall side. ... Not sure whether to attach with a stainless pop rivet and washer or use some of that firewall 2000 rtv stuff in blobs between blanket and firewall. This blanket has alum on one side, stainless on the other, and ceramic sandwiched in between. I don't want the blanket coming off years from now and was wondering what kind of pop rivet spacing you think would do the trick?