Bill Freeman wrote:

Paul,

I would bet that the aluminum radiator is furnace brazed
rather than epoxied.  I must correct the comment that
epoxy expands less than aluminum.  First, it depends
a lot on what kind or epoxy, hardener and fillers are used,
but in most cases epoxies have a substantially larger coeff
of thermal expansion (CTE) than aluminum.   I do modeling
with all sorts of mechanical and electronic assemblies and a
 common problem is epoxy potting expanding or
contracting and breaking or bending something.  As a
matter of fact, the highest CTE that I ever saw was for
a flexibilized epoxy potting.   It had a CTE of about 225
parts per million per deg C. Of course, all epoxies are not
that high, but many are MUCH higher than most metals.
 For reference, (from memory)  steel is about 12 ppm/deg C
and aluminum  is around 25 ppm/deg C.

Another small point.   Jeff was asking about a delta P
fuel pressure gauge, presumably to better isolate  the
effects of injector pulse width on fuel quantity injected.
Do these injector  operate at choked (sonic)
flow in the nozzle?  If so, delta P is irrelevant.  Only jet size
and pulse width will be factors if the nozzle is choked.

Bill

I am pretty sure that Taurus core was epoxied. I would not be
a bit surprised if the epoxy CTE was taylored to that use.

I also have evidense to suggest Griffin cores are 
also epoxied. If no reason other than  Fluidyne claims thier
cores are NOT epoxied :-).

BTW I don't think there is not a heck of a lot of difference 
in the melting temperature of hi temp epoxy and aluminum 
solder or aluminum brazing material. I could be wrong.
Aluminum starts to soften at 500 F and some epoxies go
go to 300 F. The brazing material is between those
two number I would guess.
 
Paul Lamar
 
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