>
>> 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 aluminium for aircraft use.
>>
>
> My local BMW expert says for reliability purposes replace the
plastic
> radiators every two years. I had two fail in a six year period.
>
> Hans
>
Hans; the big thrill is when the tank on the heater core blows
apart as
you
are sitting there just idling in traffic. I have had that happen
with two
'beamers.' I don't know whether their plastic tank is worse than
anyone
else; but, I do still know that I have had to replace several of
their
radiators as well. Maybe Europeans just don't make as good a
plastic as
Matt
wants; but, while I joke about using pvc and/or glass almost
anywhere, off
the ground, in a pressurized situation in an engine compartment is
just
not
going to be it, for me, anyway.
jofarr, soddy tn
Where did it break? The normal points are either the hose
connections or
the plastic lip that the
tabs bend over. These are the design fault points, BMW is renowned
for
while making a quite
high tech car that goes really well when it is all working, they also
make it so that it has a
rather high maintenance cost.
Don't like plastic fine
Then aluminium or steel (Just can;t see in)
Or another way is a thin sheet of perforated aluminium wrapped around
the plastic tube.
as an additional pressure support.
The choice is still yours.
No matter which type of tube it is about the same effort to make.
Except for the aluminium wrap
Regards David Gaze
One method of finding the position of the piston inside a non magnetic
cylinder is to fix a small magnet to the piston and use a
wristwatch compass
moved about on the outside of the cylinder. A ring of iron wire
around the
piston as well as the magnet may make it easier to find. On a plastic
cylinder a "stud finder" will sometimes work.
Colin Smith
Once the piston position is correlated to the pressure gage in the
cockpit, you will always know its location. I am thinking of setting
up the floating piston to maintain coolant pressure at 20 psi and
using a 26psi cap on the swirl pot as a safety. Opinions? Jerry
Why plastic? Why not aluminum? You are asking for it with plastic.
Do you really want to fly around with a critical plastic part in your
airplane subject to 250 degrees F and 26 psi.
Plastic is cheap. That is its only advantage.
Paul Lamar
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