Group,
  After over 11 years of building on a  Glass Goose, I may be    finished.
Not
finished in a good way, though.  I filled my wing tanks several months ago
and was delighted to fire up my Renesis.  Today, a month later, I noticed
the leading edge cap separating from the wing near the wing root and leaking
out of it.  With further investigation, I also discovered leaks on the
bottom of the opposite wing at the shear web.  The residue of the leaks is
yellow-tan in color and sticky.  My conclusion is that the alcohol in the
gas has had an adverse affect on the epoxy.  I'll call the epoxy maker on
Monday to get his words.  I read about the effects of alcohol on epoxy on
the internet several years ago but was assured that it wouldn't affect a
tank that was Jeffcoed.  Sealing the tank is the least of my concern.  What
makes me think the wings are now unreliable is that the fuel has wicked up
into many areas of the wings' integrity so, at this time, I don't think I
can trust them.  I offer this as a warning to those that can use it.  Do any
of you have any ideas or words that
   Sandy McNabb
   Renesis in a Glass Goose  (retired)


   Sandy,
   What kind of Epoxy did you use,  was it EZ Poxy? I am
   assuming you jeffcoed the tank based on what  you wrote am I correct?

   Does anyone know of any protection for  composite built aircraft
  for the
   problem described here with alcohol  laden fuel or ethanol? FYI, fuel
   bladders is not a workable solution  for most composite airplanes.

   James Ealey

   I am  interested in your reasons on why fuel bladders is not a
   workable  solution for most composite airplanes. Are you speaking
   of the blue  foam Rutan method?

   Paul Lamar


   Yes, the Rutan  designs are what I was referring to with the blue
  foam.
   With these  designs unless you get specially made bladders and you
  are
   will to  eat the weight penalty you will
   definitely lose something that the  design offers in performance.

   James Ealey

   Auto  fuel is a 25% savings in fuel cost. I don't have a weight per
  square
   foot yet on the McMaster neoprene nylon material but it can't be
  much
   at only .022 inches thick. I'll order $5 worth and weigh it and  do
  some
   fuel tests on it.

   Custom built was what I had  in mind for the fuel cells. One can
  hammer
   ribs out of sheet steel  and use them to clamp and heat the joints.
   I suspect something like  250 F will do the job.

   It will take a bit of trial and error to  learn how.

   Paul Lamar


   James,

   I have a wet wing  with fuel in the whole leading edge rib   sections.
A
few holes are cut in the lower rib to let the fuel flow.  The building plans
call for sealing the surface area of all of those D sections plus the holes.
It is a daunting task and I doubt I can accomplish it with 100% certainty.
Worst get the outer skin is added later and those joints can't not be
properly sealed.  Since I am exploring using high ethanol content fuel, I'll
be hiring someone to weld thin 0.3mm Teflon bladders for me.  With the
absence of JeffCo coating the weight increase will be nelgible.  I haven't
figured out the connection method between them yet.  Probably need some
male/female tube connections welded on.  Bladders can be designed to
collapse if desired.  Sandy, I wouldn't scrap the wings yet.  Chances are
the ethanol is reacting with the epoxy surface or remaining wax.  I don't
know which type of resin you used but some of the vinyl-esters are
specifically designed to hold solvents.  Chances are good you can drain the
fuel heat up the wings to 25C and evaporate the remaining solvent out of
them.  If you are concerned with the integrity of the wings, make a jig and
load test them with sand bags.  After passing that test you can make a plan
to add bladders.  Water infiltrating into fuel tank depends a lot on the
tank material, vent air temp and humidity.  Naturally amphibs.  operate in a
humid environment.  Having the wing tanks feed a low sump tank is also a
good idea.  Pump pick-ups should be at least a half a gallon volume above
the bottom of this tank.


   Doug in Japan

   Those big tanks in the  ground at the gas station are now vinyl
  ester. It
   seems that tanks made of  vinyl ester or lined or doubled up with
  vinyl
  ester
   would do fine. Or if you  have a TIG machine, or better yet, a
  friend with
   a TIG machine, repair the  damage with whatever epoxy you built
  with and
   make up some nice aluminum  tanks. Or, race car fuel cells come in
  many
   interesting shapes and sizes and  the smaller ones are cheap
  enough. You
  can order
   the bladder without the  steel can. Check out ATL
   http://atlfuelcells.com/

     (http://atlfuelcells.com/)

   and


   http://www.buycheapr.com/us/result.jsp?ga=us3&q=racing+fuel+cells


   http://www.buycheapr.com/us/result.jsp?ga=us3&q=racing+fuel+cells


   Lynn E. Hanover


  I think teflon is over kill.  I am not sure it is easy to weld.
  Reliable
  bonding is a problem.  Polyethelene is what most solvent bottles are
  made
  from if they are not glass.  It is a well behaved thermoplastic and
  can be
  welded.  Harbor Freight has soldering iron like tools for plastic
  welding;
  hot gas jet. McMaster has poly sheet in the catalog.

  Murry I. Rozansky

  Thanks for the harbor freight tip. I am going over there today
  to get some polishing pads.

  -------------------------------------------------------------------

  I think Polyethelene  would be too stiff for retrofit through small
  holes.

  If there are 2 ribs in your tank it could be done by cutting two 6
  by 12
  holes
  oval holes with three custom made bladders. The edge of the holes
  are near
  the
  ribs so connections can be made to the next bladder. I suspect it
  does not
  take
  long to make a custom bladder.

  My 182 has a dozen access holes in the bottom skin :)

  Sandy, Contact your local EAA chapter for help building the new wings.
  All EAA people can learn from your experience.

  Also get a bore scope and take a look inside. The harbor freight
  unit is
  marginal but home depot now sells them. I suspect it is better.

  Paul Lamar

  --
  Group,

  Sorry I haven't gotten back to y'all sooner. I've been on a three
  day London
  trip. To answer some questions, the epoxy I used is what the kit
  supplier
  sends me: CER 112-2 resin and hardener. I've talked with the
  technical guy
  at the supplier (Cass Polymers, Madison Heights, MI) and he has
  confirmed
  that ethanol is very detrimental to their epoxy. I suspected that from
  conversations on the internet, however, I was assured that if I use
  a JeffCo
  lining in the tanks, there would be no issues. It's now obvious that
  it's
  not the case.

  The airplane has wet wings with 3/8' foam covered with fiberglass.

  When I first started this project I promised myself that I would not
  ever
  fly this airplane if there were any doubts about its safety. I now
  have
  doubts about the integrity of the wings. They may be just fine,
  however,
  even with borescoping and testing, I think I'll still have some doubts
  because the spar is in the wet tanks and has been exposed to ethanol
  for
  over a month. If I was satisfied that the integrity is still in
  tack, I'd
  still have major challenges with correcting the ethanol issues with
  the four
  wing tanks. Actually, the four wing tanks are subdivided by the spar
  in two
  tanks, so blatters and/or sealing would certainly be a major
  challenge. I'll
  certainly make anybody a good deal on the project if they want to
  give it a
  try with the understanding that I think the airplane is quite
  possibly not
  safe and the wings should not be used. The project is complete with
  the
  exception of attaching the tail and building a cowling.

  So, at this time, my first plan is to strip the airplane and donate
  it to a
  school or museum and part out the rest. I've got a 2005 Renesis with
  5,000
  miles on it that runs like a champ. The engine was rebuilt and
  ported by
  Bruce Turrentine. If I can't donate the airplane, then I'll try to
  sell it
  in one piece as much as possible (short of the wings which I will
  probably
  saw off) minus the avionics which I'll use in my next project. Oh
  yes, I'll
  be starting a new project soon. I'm kinda stubborn.

  Did I miss any questions on this thread?

  Got any ideas on how to donate it and to who?

  Sandy McNabb
  Renesis in a Glass Goose (retired)

  IMHO parting it out is not a good option. You have years installing
  the engine and cooling system unique to a Glass Goose. All that effort
  would be wasted if somebody bought just the engine for installation
  in some other type of aircraft. I have first hand experience with that
  as I bought a flying RV4 with a rotary engine. I was mightily
  impressed with all the thought, time and labor Mike Wills put
  into the airplane. It would be a crime against humanity to part it
  out :) It my opinion it was a stupendous bargain.

  It would be a good buy for somebody else building a Glass Goose.
  I would focus on selling it to that community if not the rotary
  community..

  Also I would not saw off the wings just yet. Further inspection
  with ultra sonic techniques may prove they are not as bad as you
  think. I would find a structural engineer and get his opinion.

  Paul Lamar



Sandy,

Mark Forse, who teaches a composite workshop for EAA says that Abaris
company is the premier place to take composite training...they have courses
for industry people.  Maybe you can consult with them and get an opinion
about what to do?

Gene Kahn

--
Wasn't there a huge problem with de bonding of the wing skin from the
ribs/spars on the original Glass Gooses? Maybe that is part of the
problem--poor original bonding?


Marc (who once considered them after the kits were modified by the TX guy)


----------------------------------------------------------------------------
---------

Gene....thanks. I'll look up Abaris company.

Marc....Some of the old Seahawkers (pre-Glass Goose - three I think) lost an
upper wing (one side). One due to aileron flutter and the other two due to
weak wing spars.  They didn't have ethanol back then. The two issues have
been corrected in the current Glass Goose. By the way, I heard that all
three made successful landings....successful in that nobody died.

Sandy McNabb