>
>      >
>        > What I will use - since I am not into inverted flight ( yet
>      ?  LOL ) I
>        > will use the idea of the cylinder rather than the bladder.
In the
>        > cylinder - CPVC maybe - I will have the fluid on the bottom
and the
>        > coolant line at the base with the air fitting at the top, but no
>      piston
>        > and no spring - rather a solid foam ball floating in the coolant
>      with
>        > only a few mm clearance between it and the walls. It will
keep the
>        > liquid from sloshing near the base and keep mostly air above it.
>      Fail
>        > safe in most modes of flight.
>        > -dave
>
>
>      Dave
>
>      You are joking right?  Plastic unless you are talking Teflon is not
>      the best
>      substance to hold up in a stressful environment like an aircraft
engine
>      compartment. I have lots of late night experience replacing CPVC
of all
>      grades in pool filtration systems that are subjected to expansion
>      contraction cycles. The stuff micro fractures and is they are not
>      apparent
>      until sudden failure.  Ie one large crack. Hard foam abrades and
>      ends up
>      clogging the radiator.  Terrible for heat transfer characteristics:)
>
>
>      Go with aluminum if possible. Lots of tested vessels on the market.
>
>      Doug in Japan
>
>      -----------------------
>      Doug,
>
>      I was not going to use CPVC it does not have the right properties.
>      does not support a high temperatures.
>
>      I can use any of the following, it is individual choice.
>
>      Steel wall thickness 1.0mm to 1.6 mm
>      Aluminimum wall thickness 2.0 mm to 4.0 mm
>      Plastic wall thickness approx 8.0 mm
>      There a only couple of types on the market that suit.
>
>      The properties required for the right type of plastic are,
>      high heat support at least (140 deg C)this rules most plastics
out on
>      the spot.
>      high impact
>      high pressure (this rules out most others)
>      able to see into it (tanslucent at a minimum)
>
>      They are only a very few that meet these requirements.
>
>      So if you want metal thats fine the functions are exactly the
same just
>      the tube material changes.
>
>      Regards David Gaze
>
>
>
> Lots of (most?) modern automotive radiators have plastic tanks (on the
> ends of the core).  There ARE plastics that will survive the temps and
> pressures...
>
>
> Matt-
>
> Yes but they are troublesome. It is automotive practice to use
> a 15 psi radiator cap but most rotary powered aircraft are now using
30 psi caps.
> I see no advantage in plastic over aluminum for aircraft use.
>
> Paul Lamar ...No rotor no motor.


There is always transparent aliminum!
--
Blake C. Lewis

That is a new one on me. In fact I have never heard of
aliminum let alone transparent aliminum :)