Thanks for these tips Nigel, they will be a big help in putting my plan
together.
Will keep you informed.
This Europa forum is a marvellous thing!
Cheers
Sue and Bill Sisley
On 12/11/2013 10:38 p.m., nigel_graham@m-tecque.co.uk wrote:
> Hi Bill
> If you are serious about constructing your own alloy tank, here are
> some of the issues that I considered carefully before embarking on
> what turned out to be a lengthy project.
>
> Capacity
> If you want to maximise capacity, the tank shape will be complex to
> take advantage of the available space. I went "full span" and put
> seamless tubes through to accommodate pitch control and rudder cables.
> Since you have sawed off the top of your cockpit module, there is now
> room to extend the tank vertically up by about 100 mm (to the door
> sill), this should give you an extra 18 litres. Restore the strength
> of the CM joint using standard "good composite practice".
> This should not compromise the seating or baggage-bay access.
>
> Mounting
> The tank cannot sit on the bottom of the fuselage but should be clear.
> Incorporate supporting brackets to spread the (considerable) load to
> the front and rear of the cockpit module (seat back). Design in some
> method of allowing the tank to expand and contract - sitting it on a
> rubber or cork mat for instance.
>
> Breathing
> Use considerably larger breathers than were originally fitted - to
> prevent pressure build-up and blow-back while filling. If possible use
> two, one on each side of the tank. I routed mine up and then down,
> venting under the fuselage, to prevent siphoning or fuel dumping in
> the event that the aircraft ever flipped over.
>
> Fuel Return
> I pondered the ideal configuration for the fuel return line (discussed
> ad-nauseum since!) and opted to return it to the top of the tank. A
> vertical cross-drilled pipe inside the tank allows the fuel to dribble
> down without vapourising or having to contend with the back-pressure
> of a full tank.
>
> Fuel Level Monitoring.
> There are now far more options available to accurately monitor the
> fuel contents. Capacitance level sensors work well but are sensitive
> to fuel type, if you only ever use one type of fuel, this won't be an
> issue. They can be used with a "lookup table" to linearize the readout
> giving an accurate indication of fuel contents. Float switch stacks
> are the next option, (as supplied by Europa) they are reliable and not
> fuel sensitive but give a non-linear indication. I opted for the
> former but included four optical sensors to give an independent
> indication of fuel contents at "Full", 2/3 1/3 and "Reserve" and chose
> to delete the standard "stand pipe", which, without any method of
> isolating, I considered a safety risk.
>
> Maintenance
> Now is a good time to include an inspection hatch. Machine a large
> diameter "weld-in" ring with matching cover, tapped for at least six
> bolts. Include a groove to accept a Viton "O" ring to seal the joint.
> This cover also makes an ideal mount for the fuel level sender.
>
> Good luck and keep us informed of progress.
>
> Nigel
>
>
> On 11/11/2013 22:43, bill wrote:
>> Thank you Nigel,
>>
>> Having got the top off now I can see that the leak is at the shelf on
>> the front of the tank where it sits on the mount. It appears that the
>> fibreglass had bonded to the tank and with movement caused a fracture
>> due to the stress. Having looked at the tank now which is very
>> deformed and reducing capacity, I am sure a "metal" one will be much
>> superior. Fortunately there are some very good craftsman around here
>> so fabrication will not be a problem. Not sure we will get to the
>> same volume as you have but will certainly look for more than I have
>> now. Will send some pic,s when all done.
>>
>> Regards
>>
>> Sue and Bill Sisley
>> On 12/11/2013 8:55 a.m., nigel_graham@m-tecque.co.uk wrote:
>>> Hello Bill,
>>>
>>> I'm a bit late getting back on this one but as others have said, I
>>> built a tank out of 5251 quarter-hard magnesium alloy.
>>> It weighs 7850 grams and has a capacity of 110 litres.
>>> I incorporated internal baffles, and breathers with proper AN
>>> fittings to accommodate alloy pipework. It is also fitted with a
>>> full length capacitive probe and four solid-state optical fuel level
>>> sensors.
>>> http://www.europaowners.org/main.php?g2_itemId=28719
>>>
>>> The only advice I would offer is: allow yourself a long time to make and
>>> perfect
your cardboard templates - the fuselage is partly conical in section so
the development will be an interesting shape. Choose a welder based on his
ability
to weld alloy and don't fall into the trap I did of restricting yourself
to a CAA approved welder whose self-belief exceeded his ability!
>>>
>>> Nigel
>>>
>>>
>>> On 08/11/2013 21:37, bill wrote:
>>>>
>>>> After 1100hrs I have suffered a failed fuel tank on my XS Mono. Not
>>>> sure exactly where the fault is other than it is high up on the
>>>> tank. Will know more when I get it out.
>>>>
>>>> My question to the forum is, has anyone tried fabricating a metal
>>>> (aluminium) tank rather than using the Polyethylene plastic one as
>>>> supplied with the kit. If so, were you able to obtain the same
>>>> volume and any other advice you may be able to offer.
>>>>
>>>> Many thanks
>>>> XS Mono
>>>> Kit 456
>>>> 914 and Airmaster
>>>> 1100hrs
>>>>
>>>>
>>>> Sue and Bill Sisley
>>>>
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