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My fellow composite and/or alternative engine devotee's, as y'all may
remember from this very forum and now also in the CSA Newsletter (No 92)I
had a bit of an issue with Jeffco sealant failing in the strake of my
Velocity SE. In some areas it failed in mass, in others, it faied in smaller
areas....however, any failer is not only unacceptble and cause for concern
it is also just a real PITA.
I have replaced the inner skins of the right strake and have the process
down and shall start the left strake asap. The new glass is being layed up
with fresh EZ-84 epoxy.
I have taken some of the "good" cut out Jeffco sides from the strakes, as
well as some EZ84 parts I had aroung the hangar and have had them soaking in
Auto fuel (purchased from the pumps just across the street from EFD) which
is up to 10% ethanol, for about a month. When I have examined the pieces,
both Jeffo and EZpoxy, all seems ok. No separtion of the Jeffco from the
EZPoxy and niether seems to have softened. Softening is one of the problems
I have seen discussed.
I am at a point of chosing if I should finish the strakes out by trying to
apply Jeffco again or just staying with straight EZpoxy. I have a new $450
batch of Jeffco in the hangar and a couple of new gallons and a half kits of
EZpoxy....that cost is done, so cost is, and never was a factor. I read Gary
Hunters reply to my problems in the CSA newsletter (Gary has been to my
hangar a few times and was my EAA tech counselor for my first conditional
inspection a while back) and his comments on Jeffco sometimes having
problems with adheasion is taken to heart. Due to this and my Jeffco failure
I am leaning towards staying with straight EZpoxy. I have read here (or
related email lists or likely both) of folks flying with straight EZpoxy
strakes for decades....even with Ethanol and other additives in the fuels.
My reason for using Jeffco in the first place was due to the "conventional
wisdom"....or so I thought (ie, list servers, Velocity, Inc etc) that it was
the stuff to use to eliminate concerns about fuel additives, ethanol,
diesel....guess not.
So, since I am using an auto conversion and continue to plan to use auto gas
should EZpoxy be up to the task? I know some have said it will, but I am
asking for confirmation of this data point in case I misunderstood. I am
confidant that EZpoxy WILL adhear to EZpoxy and I can add to what I have
already used to rebuild the right stake and now on the left strake.
Obviously the idea of not only having to do this again, not to mention the
anxiety of even have to worry about it at 10000 feet....or 10 feet....or 500
feet AGL is not the way I hope to fly my plane.
I have also made some test strips of new lay-ups of EZpoxy satuated glass
onto Jeffo. I let it cure and returned the next day. I could not pull the
test strips off the Jeffco without it destroying the glass. The bond did NOT
separate at all, The glass itself faild, not the Jeffco to EZpoxy bond. I
did this with well sanded surface as well as surface that had no sanding on
both Jeffco to EZpoxy and EZpoxy to Ezpoxy. All bonds seemed very
stout...howerver, neither of these batches have been soaked in
Autogas/ethanol.
I will also be looking into the proseal that Gary mentions as well. It too
had been mentioned but I thought it was more for sealing leaks but I shall
endeavor to find out.
Also, I expect to fill the strakes with water and let set for a while and
see if I have leaks before I seal the strake tops back on. My hangar partner
just did this with the VariEZ he is restoring. He is haveing to address
leaks in his stakes as well, just not caused by a bad Jeffco application.
Come on guys/gals, Wayne, Terry, John and all else, what say ye. This is
when I need some cold, hard commentatry, thoughts, concerns, brain farts
etc. It is appreciated.
Thanks.
All the best,
Chris Barber
Houston
BTW, I will try to write in a more "publishable" manner in case my writing
may show up on CSA again....geeeeszz, when you read what you wrote in e-mail
in a more formal published form it makes you kinda cringe...wait, maybe I
need to re-read this........naahhhhh, I got a plane to build
FINALLY, the Wings over Houston Airshow is coming up on Oct 25/26. On the
25th, Saturday, EAA Houston, EAA Chapter 12 will be having an open house in
my hangar Alpha Papa. Please, if you can make the Airshow, please stop by
the hangar and say Hi. I will be the guy trying to explane why my strake
tops are cut open.
__________________
Christopher Barber
Velocity SE/FG w/yoke. Zoom, zoom, zoom.
www.LoneStarVelocity.com
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