Mailing List lml@lancaironline.net Message #62466
From: Bill Harrelson <n5zq@verizon.net>
Sender: <marv@lancaironline.net>
Subject: Re: [LML] Re: LN2 queries
Date: Thu, 28 Jun 2012 14:08:43 -0400
To: <lml@lancaironline.net>
Colyn,
 
On the 320 my firewall installation is 100% stock. The manual calls out a layer (or was it two?) of fibrefrax and stainless on top. You might be thinking of the IV which uses a blanket type arrangement. Not sure what’s used on the Legacies.
 
Bill Harrelson
N5ZQ 320 2,050 hrs
N6ZQ  IV under construction
 
 
 
 
From: Colyn Case
Sent: Thursday, June 28, 2012 10:27 AM
Subject: [LML] Re: LN2 queries
 
Bill,
 
Covering the firewall with stainless seems like a big improvement.  I see you dispensed with the blanket?  ....or did you?
What is the rationale for eliminating the insulating effect of the blanket?
 
Colyn
 
On Jun 27, 2012, at 6:41 PM, <marv@lancair.net> <marv@lancair.net> wrote:
 


Posted for "Bill Harrelson" <n5zq@verizon.net>:

Rob,
 
I did not ground (earth) any of my fuel tanks. I am not aware of any 320/360
builder who has done so. Having said that, it is certainly not a bad idea as
long as you do it in a lightweight manner.
 
As far as the fibrefrax, it’s good stuff. I put it in beneath the stainless
steel firewall per the manual. What I found is that under compressive loads it
gets squeezed flat causing the stainless to wrinkle. This will have little or
no practical implication...but it looks like crap. I removed everything from
the firewall and replaced the fibrefrax with washers everywhere that something
was bolted to the firewall. This included the engine mount bolts. Now, I have
solid, no compression, surfaces at the bolts and no wrinkles in the stainless
while retaining the heat/fire resistance of the fibrefrax.
 
The first photo shows the fibrefrax cut out around the washers (phenolic
behind the battery) and ready for the stainless to be added.
The second photo is the completed firewall with everything torqued down and
no wrinkles. I burnished the stainless with scotchbrite and a hand drill.
 
Let me know if you need more info.
 
 
 
Bill Harrelson
N5ZQ 320 2,050 hrs
N6ZQ  IV under construction
 http://www.mykitlog.com/harrelson/
 
 
 
 
Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster