This is posted with the permission of the writer from the "Nopistons" web
forum. It was in answer to a question about the reliability of the apex seals
offered by RWS . It may be of some value in building an aircraft engine.

http://www.rotaryaviation.com/engine_products.htm

Lynn E. Hanover

Posted: Jan 30 2004, 02:54 AM
F.N.G.
Group: Members+
Posts: 46
Member No.: 9,364
Joined: 27-December 03

Member is:

 I tested a set out of my own curiousity...
I built an engine using one of their kits, and then installed a switch onto
the rear rotor secondary injector, and cut the injector off at 12 psi and 5000
rpm. Obviously, this induced some detonation

The rear endplate cracked, all of the corner seals broke, and 5 side seals
broke near the upper ends of them. ONE apex seal cracked where the corner piece
meets the "long" section of the seals, at the corner of the longer piece.
The apex seal stayed in the groove, and the chunk remained in position.

I emailed Rotary Aviation to ask to purchase another seal and a few other
parts to rebuild the engine, and they were shocked to hear it failed at all,
despite the conditions I described. They offered to replace the seals for free. I
declined, simply b/c its not fair to charge them when I was simply testing the
seals against detonation. Despite my request against it, they mailed me a
FULL set of replacement seals for free, and told me the ones I tested were a
weaker preliminary version (I tested their seals with the single apex sealsprings;
the new ones come with dual springs like stock.

These seals are fantastic. I have them in a couple engines, with one holding
20psi. Under extreme detonation in each rotor combustion face, only one of the
seals let go, and all of the other faces must have experienced detonation,
and this was on their "crappy" seals.

RWS's service is fantastic. They make a good product at a fair price
(although I don't really like the fitment of the SAE viton oil control o-rings).

The seals, however, take a long time to break in. I find peak compression is
achieved at 5000 miles on used, good condition rotor housings.

Geeeez!!!!!!!. This guy is SERIOUS!!!!!!!!!!!!!!!!!!!!!!

I wonder if he used the 3rd gen corner seals and end housing?:
BTW guys these are 2 mm and not the more robust 3 mm apex seals.

I thought Tracy was shipping teflon encapsulated oil control o-rings.
These fit perfectly in my engine.

Paul Lamar
 
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