Yes, it looks like I’ll be replacing
the old 5/8” bushings with ¾” bushings supplied by M/T. To use
these, it requires opening up the six holes in the re-drive hub to .756”
in order to accept the M/T bushings. I need to check with Tracy on the best way to ream the holes as
the hub is hardened 4130.
Mark S.
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Bobby J. Hughes
Sent: Wednesday, December 22, 2004
8:32 AM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: Oil
coolers
Mark,
Did you ever figure out a good solution
for you MT Prop / RWS redrive problem? This is the combination that I am
looking at.
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Mark R Steitle
Sent: Wednesday, December 22, 2004
8:24 AM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: Oil
coolers
Bobby,
Comparing the pictures to my Fluidyne
cooler, the perma-cool design looks like the same size would be lighter, but
less durable. The fin spacing looks to be less dense on the
perma-cool. But then its hard to tell much from a picture. Mounting
would be an important issue, but possibly easier for a lighter unit.
Mark S.
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On Behalf
Of Bobby J. Hughes
Sent: Wednesday, December 22, 2004
8:17 AM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: Oil
coolers
I found this company
while researching oil coolers. Does anyone have any experience or information
about these products. They advertise they pressure test the coolers to 300 psi.
Fluidyne advertises testing at 200 psi. They look rugged.
http://www.perma-cool.com/Catalog/Cat_page10.html
Bobby Hughes
From: Rotary
motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Tracy Crook
Sent: Tuesday, December 21, 2004
11:33 AM
To: Rotary
motors in aircraft
Subject: [FlyRotary] Re: Oil
coolers
http://www.fluidyne.com/pl_theoc.html
Really
liked the DB 30517 (3.75" thick double pass model) Will probably use
this one on my -8.
Tracy
Perhaps you mean use “two”
instead of “this one”. I looked closely (longingly) at the
fluidyne when I was in the market for a cooler; but they just don’t make
on with the capacity for the 20B. One DB 30517 would handle neither the
flow nor heat rejection needed; however 2 in parallel would do it. At
least that’s what my analysis says.
Al
Nope,
at least I don't think so. Here's my take on it.
The
Mazda cooler has 180 CU In. core area and gives me enough cooling for the
13B. I'm assuming for now that the dimensions for the Fluidyne are core
area (must check) which give it 275 cu in, which is 153% of the Mazda.
Pretty good match, at least on paper. The "effectiveness
quotient" for the Fluidyne at almost double the thickness is not as
good but I'm hoping the much better ducting and pressure recovery on the -8
will cancel that out. The higher delta T air temp will give less cooling
drag, at least in my universe : )
In
any case, the main -8 mission calls for 100 HP at >=18,000
ft. It'll work.
Tracy (please
don't ask me to define "effectiveness quotient")