|
320 SS turns black after a while. Not sure what
Ed's is, might have a different alloy in it.
Greg Ward
----- Original Message -----
Sent: Thursday, February 05, 2009 5:41
AM
Subject: [FlyRotary] Re: Tube Thickness
[FlyRotary] Re: 20B manifold
Ed,
Mine turned black. Hmmmmm
Mark
On Thu, Feb 5, 2009 at 6:58 AM, Ed Anderson <eanderson@carolina.rr.com>
wrote:
For what it's
worth, George, I had my exhaust manifold made out of the stainless
steel pipe used for stair railing that Mark mentioned. The walls are
approx 0.10 -0.12" thick. Mine has lasted over 500 hours and 10
years. It appears to be 304 SS, but I can not swear to that.
There is some minor scaling and it does eventually turn a rust color –
at least mine did. I've been very please with it. It's wall
thickness also makes it easier to weld in bungs for O2 and temperature
sensors than thinner wall tubing. Also it was much cheaper than buying
SS exhaust tubing and you could get just about any degree bend you wanted
from stock rather than paying cost for special bending.
Ed
From:
Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of George Lendich
Sent: Wednesday, February 04, 2009 5:15
PM
To: Rotary motors in
aircraft
Subject:
[FlyRotary] Re: 20B manifold
I thickness of the tube is what
I was after.
----- Original Message -----
Sent:
Thursday, February 05, 2009 7:59 AM
Subject:
[FlyRotary] Re: 20B manifold
If
you're asking how thick my 20B exhaust flanges were, they
were 1/2" (12mm). I made them this thick so they
would provide support for the exhaust system. Tubes were a
press fit and were welded from the back side. That part of the
design has worked great... although probably heavier than
necessary.
Regarding the Renesis manifold, there is a bunch
of cast material that could be removed to lighten it up. But I
agree that it would be best to build a lightweight exhaust system from
scratch.
On
Wed, Feb 4, 2009 at 3:36 PM, George Lendich <lendich@optusnet.com.au> wrote:
How thick was that again,
1.6mm ?
Bite the bullet and make one
from scratch, Just make the thick flanges from SS ( 304 or 316) and use
the hand rail pipe as suggested - cheapest and best for the 3
rotor.
Sounds a lot lighter than the
cast manifold.
----- Original Message -----
Sent:
Thursday, February 05, 2009 12:10 AM
Subject:
[FlyRotary] Re: 20B manifold
I
have one that came with my 20B. I don't want to sound negative,
but I don't think it is realistic to use on an a/c. First, it is
incredibly heavy because it is designed to incorporate the twin
turbos. And it is made of cast iron, so it would probably melt at
prolonged WOT operation. And the passages are very
restrictive to exhaust flow. I could weigh mine and send
some pictures if you wish. Sorry, but I don't want to get rid of
it because I have plans for a 3-rotor auto installation where it would
be useable. Maybe you could modify a Renesis manifold to
fit. It would require some welding, but it is probably more likely
to work than the original 20B manifold.
The
cheapest manifold would be to use 304SS handrail material. I built
my first manifold using that material and after 100 hours it looks like
it would last for a very long time. Ed Anderson has been using
this material on his a/c for a long time. My exhause flange
material was 1/2" mild carbon steel and it was holding up fine as it
doen'st see the high heat that the pipes do. The problem was with
the mufflers. They take a real beating. Try to space the
muffler as far away from the engine as possible.
On
Wed, Feb 4, 2009 at 7:43 AM, Rob <rob@mum.edu> wrote:
Thanks for your replys on
this subject. I realize the manifold would be too heavy but I was hoping
I could widdle it down some how. Greg, I would be interested in your
suggestion for doing that. I'm putting this 20B in a
BD-4.
Robert Bollinger
MR722 MUM
Fairfield IA
52557
(641)472-7000 ex2068
(641)919-3213 cell
rob@mum.edu
----- Original Message
-----
Sent:
Tuesday, February 03, 2009 11:10 PM
Subject:
[FlyRotary] Re: 20B manifold
Al, you don't want the stock exhaust.
Get one built. If you want to know one way it's done, let me
know.
----- Original Message
-----
Sent:
Tuesday, February 03, 2009 8:25 PM
Subject:
[FlyRotary] Re: 20B manifold
Does anyone on this list
have a 20B exhaust manifold that came with their engine that I
could buy?
No; but I
do know the thing is massively heavy. I looked at one when I
got my engine, and decided quickly it was not very interesting for
an aircraft. Maybe if radically modified . . . Just my
opinion.
Al
G
|