Hi Jan
"As mentioned the aileron drive protection could also be made somewhat
larger. Comments?"
Just a note:
I remember reading years ago a few who had tank bulge and hit aileron
cross tube, just moved the cross tube from aft of arms to forward.
As far as the aft tank supporting brackets, "dang" they are supporting up
to 18 gallons of fuel and weight of tank (over a hundred pounds of
cantilevered weight). Besides the expanding and contracting evil, you have
a severe stress riser here if you follow manual. If my CPM was not bonded
in place, I would not have made all layers of BID end at the same place
but instead taper layer on the tank where first layer if longest and
subsequent layers are shorter. The tunnel bracket is a vulnerable area.
The extra BID I added will not relieve any cantilever loading or
expansion loading in the center, but will distribute load over a larger
area. Distributing loads over a "larger area is a "much more better"
thing. I would rather have my 300 lb passenger wearing flat sole foot
apparel than spike heels which will most likely go right through the floor
of Europa. Foam distributes fuel tank cantilever load (I put Mylar in
there so foam is not bonded to tank and will allow expansion). I mentioned
on the gallery that there was no bulge after foam was applied. I was not
referring to the tank but the bottom of the fuse. The high expansion foam
may very possibly deform it. I think the foam will alleviate a lot of
cantilevered stress on the aft BID brackets.
A note on building a metal tank. First off I have seen at least 1 picture,
perhaps 2 that are existing. First choice is to source to ones who already
developed. If can't have them build one more, pick their brains how they
did it. If you can't find pictures or who has them in hangar I have info.
If that comes to a dead end, an idea:
I have a metal melting machine and several chip making machines (Hobart
TRT 250 TIG, 2 laths and 2 milling machines). I welded up a thin wall
aluminium tank for a Sonerai. I purged inside of tank with argon and it
looked great. There was 1 spot in a corner that had a pit of
contamination, easy to file and re-weld.
Now for plan. Someone get hold of weldable aluminium, remember that when
you weld aluminium it goes to T-0, which means it will be soft as
aluminium a soda can is made from. After it sits depending on the
aluminium used, generally it will get harder perhaps to T-3. I am not an
expert and it has been years since I welded up an alumimium folding
balloon basket, but strength does increase with time. Thus someone find
out what type of aluminium is used in a Sonerai and other welded aeroplane
tanks and buy some. Now design up a nice square cornered 5 gallon
container and cut the pieces. File or sand the edges so were the weld is
going there is a 90 degree bevel. Don't make the bevel (22.5 degrees each
side) to form a sharp edge, but bevel only about 2/3rds of thickness. Make
sure you clean aluminium everywhere and of area to be welded, meticulous
and scotchbright 1" on both sides, then wipe down with degreaser. Now
assemble tank with dabs of JB Weld KWIK (4 minute). Oh yea before
assembly, choose a nice weldable opening and cap. Look at aeroplane stuff
in Spruce and Wicks and www.mcmaster.com . I will leave this detail to
you. For an air vent, buy a petcock that Spruce (and probably Wicks) sells
where you drill a hole, insert a grommet and then force petcock in place.
My charge will be that after I send the tank around for critique, I get to
keep it.
For a more aggressive first try, and my preference, make an aux tank for
the port side of mono! Same charge applies.
If all is a go, make the real deal. Same charge applies.
I have had great success hacking up old fork lift Worthington propane
cylinders, cutting them in half, extending and beefing up dip tube and
melting them together. All still in service since early 90s. A lot easier
to keep Europas liquid energy contained compared to a balloons liquid
energy.
My charge can be negotiated, if someone delivered bits and pieces and
helped weld thing up (day to 3??), and helped a bit on my build........
Ron Parigoris
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