Return-Path: Received: from [24.25.9.103] (HELO ms-smtp-04-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 4.3c3) with ESMTP id 880753 for flyrotary@lancaironline.net; Sun, 17 Apr 2005 07:59:14 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.103; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-185-127.carolina.res.rr.com [24.74.185.127]) by ms-smtp-04-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id j3HBwQL5017788 for ; Sun, 17 Apr 2005 07:58:27 -0400 (EDT) Message-ID: <002301c54344$cb421570$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Apex Seal Groove Wear and Air Filters was Re: [FlyRotary] Re: New rotors, New housings Date: Sun, 17 Apr 2005 07:58:39 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0020_01C54323.4400D9F0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1106 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_0020_01C54323.4400D9F0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Re: [FlyRotary] New rotors, New housingsThanks, Leon Having experienced the ultimate down side of "dust Lapping" (regardless = whether helped along by a foreign object or not) and seeing how cheap it = is to install a air filter installation, I am certainly going to install = one. A filter can not hinder power development as much as a busted apex = seal {:>). =20 Ed A ----- Original Message -----=20 From: Leon=20 To: Rotary motors in aircraft=20 Sent: Sunday, April 17, 2005 2:09 AM Subject: [FlyRotary] Apex Seal Groove Wear and Air Filters was Re: = [FlyRotary] Re: New rotors, New housings Hi Guys, Just need to clarify something that I have been discussing off list = with Ed. I don't THINK (but I'm not really sure) that his apex seal = collapsed and did the damage. The grooves are not badly worn enough, = nor are the seals sufficiently thin enough to turn in the grooves. Apex = seals don't normally break unless clouted by some obdurate object, and = we can't blame insane RPM or detonation as the culprit either. So while = the jury remains out on it, I remain of the opinion that his engine = swallowed something solid in the shape of the diamond impressions left = in his rotor.=20 Further, I thought I'd offer a little diatribe/rant on "Ingestion of = Foreign Objects" based on 32+ years of observation and experience with = Wankel engines. As an aside, I cracked up when I read a "Japlish" = exhortation that was included in the instructions of a HKS turbo kit I = purchased back in the early '80s. It said: "Prease being careful not = to allow any alien into port" Prescient advice indeed! Now over the years, I have found that the major cause of apex seal = groove wear is ingestion of abrasive material. The air ALWAYS contains = a certain amount of fine dust, except just after a rain storm. Proof = of this is the patina of crud left by said rain on any shiny surface, = most obvious on car duco. Here in Oz, we often get thick orange/brown = dust deposits from dust storms originating out in the desert hundreds of = miles west of the city on the other side of the Great Dividing Range. Now that very same dust, invisible though it may be, will act as a = fine lapping paste: if allowed into the engine, will, depending on the = concentration, sooner or later eventually chop out the apex seal = grooves, and the corner seal grooves. It will accumulate in the = grooves and the lapping action gets worse over time as the paste gets = thicker. Ed has told me that there is some construction work going on near his = hangar, and his aircaft is often covered with a film of dust. That = dust will also be all over the tarmac, taxiways, on the grass verges, = and in the air itself. If you are following another aircraft, you are = GUARANTEED to cop a lung full of fine dust, whether you can see it or = not. It stands to reason, seeing that any engine is just an air pump, = that it will act as a very efficient vacuum cleaner. Which gents, is why you should always supply your engine with nothing = but clean filtered air AND fuel. Most people wouldn't THINK about = running a fuel system without a fuel filter and a water trap. Additionally, a decent filter will also stop the rocks and pebbles, = and grains of sand that can get thrown up by the prop wash of the = preceeding aircraft, as well as the almost ubiquitous fine dust. = Wankel engines in particular are not very tolerant of being fed a meal = of anything solid. One small pebble, or a decent sized grain of quartz = sand or bluestone is sufficient to take out an apex seal. (And please = dont' tell me it can't happen as I've seen the results with my own eyes = on more than one occasion). I realise that there will be a bunch of people on this list who feel = air filters are un-necessary, but we can all become the victims and = prisoners of our own (often false) belief systems, no matter how = passionately and sincerely they are held. (I've no need to remind you = that there once was a bloke who said that EWPs COULDN'T cool a rotary). = So even if you do fly off water, you still can be exposed to the = products of dust storms from other parts of the country, or volcanic = ash (both often invisible - ask the guys in the BA 747 some years ago!). As a corollary, on many occasions, I have pulled down engines that = have had up to 550,000 kms on them (mainly 12A RX7 engines). Those that = have had regular servicing (regular oil and [air oil, & fuel] filter = changes) invariably have pristine rotors, that show little or = negiglible apex seal groove wear. OTOH, I have seen engine "chop out" = in as little as six months when run with a faulty air cleaner, and run = in dusty environments. Two things are important to prevent groove wear. Proper lubrication - = if the surfaces don't touch, they cannot wear - and elimination of = abrasive particles - which, when mixed with lubricant, acts as a VERY = efficient lapping compound.. Further, everyone should be scrupulously paranoid about loose objects = getting into the inlet tract. In the past 32+ years, I've seen the sad = results of just about everything being ingested - nuts, bolts, studs, = spring & flat washers, carby check balls, paper clips, lock wire = off-cuts, bits of cardboard, plastic, alloy trimmings, metal filings = and turnings etc, as well as sand, pebbles, and small rocks. NOTHING = good has EVER come of feeding a Wankel with any of this sort of = detritus. So please be extremely paranoid about inlet tract cleanliness = after working on it. While I'm on this topic, I should also exhort you to treat the = exhaust system with the same degree of cleanliness. Untill the engine = actually fires, it doesn't really know that the exhaust port is an = egress apeture. I've have seen stuff sucked up out of exhausts = (particulalry weld spatter, and even pieces of rag used to prevent = stuff falling INTO the exhaust and inadvertently left there!). =20 So that's my additional palm full of Roubles for today. Cheers, Leon ----- Original Message -----=20 From: Ed Anderson=20 To: Rotary motors in aircraft=20 Sent: Sunday, April 17, 2005 11:54 AM Subject: [FlyRotary] Re: New rotors, New housings Hi Ken, I really, really have no interest in running for your title, = believe me! {:>). I am inclined to agree that milling out the slot may = indeed take you pass some metal hardening that lessens the wear. While = I must admit that I am still a bit skeptical about the dust doing it to = me in 150 hours, I think the rotors had been run hard when I got them = but just didn't know what to check for. But, in any case I am going to = add a filter figuring it probably won't hurt. Besides, If I didn't add = a filter and something happened again, I'd never hear the end of it from = my friend, Leon. New rotors and housing are ordered. I figured depending on how = Jerry Hey and his PP project turns out, I might use them to practice = cutting PP port and then turn two of my good NA housings into PP = housings - down the road. Ed ----- Original Message -----=20 From: Ken Welter=20 To: Rotary motors in aircraft=20 Sent: Saturday, April 16, 2005 4:40 PM Subject: [FlyRotary] Re: New rotors, New housings I would look into getting 85-85 GSELE rotors with the 3 mm = seals, you would also need the weights to match them, then machine out = your rotors for a spare engine, you may need one to bale you out in the = future, if you keep this up you may knock me off the seat as president = of the dead stick club. I am now running rotors machined out to 3 mm seals and at about = 400 hrs on them I can tell by checking through the exhaust port that the = seal grooves are getting V'ed out and getting sloppy so I am now putting = another engine together, on this one the rotors are in prime shape so I = think I will run Tracy's 2mm seals. Also I think that the groves may be hardened and by machining the = groves out makes them softer as they shouldn't have worn out in only 400 = hrs. Ken Well, the decision has been made. Thanks in part to the wife's = continued interest in my warm body on cold winter nights, the decision = has been made to purchase new rotors and rotor housings. $$ but = apparently I am worth it {:>) I looked into milling out the slots to 3mm and that would have = been the cheaper approach - but cheap approach is probably partly = responsible for me being in this situation - so going to try a different = approach this time. Besides leery of using a rotor which clearly has = been subjected to sufficient loads to scrape metal off its surface and = peen over apex slot. In the process of getting quotes. Ed Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com ------=_NextPart_000_0020_01C54323.4400D9F0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Re: [FlyRotary] New rotors, New housings
Thanks, Leon
 
Having experienced the ultimate =  down=20 side of "dust Lapping" (regardless whether helped along by a foreign = object or=20 not) and seeing how cheap it is to install a air filter installation, I = am=20 certainly going to install one.  A filter can not hinder power = development=20 as much as a busted apex seal {:>). 
 
Ed A
 
 
----- Original Message -----
From:=20 Leon
Sent: Sunday, April 17, 2005 = 2:09=20 AM
Subject: [FlyRotary] Apex Seal = Groove=20 Wear and Air Filters was Re: [FlyRotary] Re: New rotors, New = housings

Hi Guys,
 
Just need to clarify something that I = have been=20 discussing off list with Ed.   I don't THINK (but I'm not = really=20 sure) that his apex seal collapsed and did the damage. The = grooves are=20 not badly worn enough,  nor are the seals sufficiently thin = enough to=20 turn in the grooves.  Apex seals don't normally break unless = clouted by=20 some obdurate object,  and we can't blame insane RPM or = detonation as the=20 culprit either.  So while the jury remains out on it,  = I=20 remain of the opinion that his engine swallowed something solid = in the=20 shape of the diamond impressions left in his rotor. 
 
Further,  I thought I'd offer a = little=20 diatribe/rant on "Ingestion of Foreign Objects" based on 32+ years of=20 observation and experience with Wankel engines.  As an = aside,  I=20 cracked up when I read a "Japlish" exhortation that was included in = the=20 instructions of a HKS turbo kit I purchased back in the early = '80s.  It=20 said:  "Prease being careful not to allow any alien into = port" =20 Prescient advice indeed!
 
Now over the years,  I have = found that the=20 major cause of apex seal groove wear is ingestion of abrasive = material. =20 The air ALWAYS contains a certain amount of fine dust,  except = just after=20 a rain storm.  Proof of this is the patina of crud left by said = rain on=20 any shiny surface,  most obvious on car duco.  Here in = Oz,  we=20 often get thick orange/brown dust deposits from dust storms = originating out in=20 the desert hundreds of miles west of the city on the other = side of=20 the Great Dividing Range.
 
Now that very same dust,  = invisible though=20 it may be,  will act as a fine lapping paste: if allowed = into the=20 engine,  will,  depending on the = concentration,  sooner or=20 later eventually chop out the apex seal grooves,  and the corner = seal=20 grooves.  It will accumulate in the grooves and the lapping = action gets=20 worse over time as the paste gets thicker.
 
Ed has told me that there is=20 some construction work going on near his hangar,  and his = aircaft is=20 often covered with a film of dust.  That dust will also be all = over the=20 tarmac,  taxiways,  on the grass verges, and in the air = itself.  If you are following another aircraft,  you are = GUARANTEED=20 to cop a lung full of fine dust,  whether you can see it or = not.  It=20 stands to reason,  seeing that any engine is just an air = pump,  that=20 it will act as a very efficient vacuum cleaner.
 
Which gents,  is why you should = always=20 supply your engine with nothing but clean filtered air AND = fuel. =20 Most people wouldn't THINK about running a fuel system without a fuel = filter=20 and a water trap.
 
Additionally,  a decent filter = will also=20 stop the rocks and pebbles,  and grains of sand that can get = thrown up by=20 the prop wash of the preceeding aircraft,  as well as the almost=20 ubiquitous fine dust.  Wankel engines in particular are not = very=20 tolerant of being fed a meal of anything solid. One small = pebble, =20 or a decent sized grain of quartz sand or bluestone is sufficient to = take out=20 an apex seal. (And please dont' tell me it can't happen as I've = seen the=20 results with my own eyes on more than one occasion).
 
 I realise that there will be a = bunch of=20 people on this list who feel air filters are un-necessary,  = but we=20 can all become the victims and prisoners of our own (often false) = belief=20 systems,  no matter how passionately and sincerely they are = held. =20 (I've no need to remind you that there once was a bloke who said that = EWPs=20 COULDN'T cool a rotary). 
 
So even if you do fly off = water,  you=20 still can be exposed to the products of dust storms from other parts = of the=20 country,  or volcanic ash (both often invisible - ask the guys in = the BA=20 747 some years ago!).
 
As a corollary,  on many = occasions,  I=20 have pulled down engines that have had up to 550,000 kms on them = (mainly 12A=20 RX7 engines).  Those that have had regular servicing (regular oil = and=20 [air oil,  & fuel] filter changes) invariably have pristine=20 rotors,  that show little or negiglible apex seal groove = wear. =20 OTOH,  I have seen engine "chop out" in as little as six months = when run=20 with a faulty air cleaner,  and run in dusty = environments.
 
Two things are important to prevent = groove=20 wear.  Proper lubrication - if the surfaces don't touch,  = they=20 cannot wear - and elimination of abrasive particles - which,  = when mixed=20 with lubricant,  acts as a VERY efficient lapping = compound..
 
Further,  everyone should be = scrupulously=20 paranoid about loose objects getting into the inlet tract.  In = the past=20 32+ years,  I've seen the sad results of just about = everything being=20 ingested - nuts,  bolts, studs, spring & flat=20 washers, carby check balls,  paper clips, lock wire = off-cuts, bits=20 of cardboard,  plastic,  alloy trimmings,  metal = filings and=20 turnings etc,  as well as sand,  pebbles,  and small=20 rocks.  NOTHING good has EVER come of feeding a Wankel with = any of=20 this sort of detritus.  So please be extremely paranoid about = inlet tract=20 cleanliness after working on it.
 
While I'm on this topic,  I = should also=20 exhort you to treat the exhaust system with the same degree of=20 cleanliness.  Untill the engine actually fires, it doesn't really = know=20 that the exhaust port is an egress apeture.  I've have seen stuff = sucked=20 up out of exhausts (particulalry weld spatter,  and even pieces = of rag=20 used to prevent stuff falling INTO the exhaust and inadvertently = left=20 there!). 
 
So that's my additional palm = full of Roubles=20 for today.
 
Cheers,
 
Leon
 
 
----- Original Message -----
From:=20 Ed Anderson
To: Rotary motors in = aircraft=20
Sent: Sunday, April 17, 2005 = 11:54=20 AM
Subject: [FlyRotary] Re: New = rotors,=20 New housings

Hi Ken,
 
I really, really have no interest = in running=20 for your title,  believe me! {:>).  I am inclined = to agree=20 that milling out the slot may indeed take you pass some metal = hardening that=20 lessens the wear.  While I must admit that I am still a bit = skeptical=20 about the dust doing it to me in 150 hours, I think the rotors had = been run=20 hard when I got them but just didn't know what to check for.  = But, in=20 any case I am going to add a filter figuring it probably won't=20 hurt.  Besides, If I didn't add a filter and something = happened=20 again, I'd never hear the end of it from my friend, = Leon.
 
New rotors and housing are = ordered.  I=20 figured depending on how Jerry Hey and his PP project turns out, I = might use=20 them to practice cutting  PP port and then turn two of my good = NA=20 housings into PP housings - down the road.
 
Ed
----- Original Message ----- =
From:=20 Ken=20 Welter
To: Rotary motors in = aircraft=20
Sent: Saturday, April 16, = 2005 4:40=20 PM
Subject: [FlyRotary] Re: = New rotors,=20 New housings

  I would look into getting 85-85 GSELE rotors with the = 3 mm=20 seals, you would also need the weights to match them, then machine = out=20 your rotors for a spare engine, you may need one to bale you out = in the=20 future, if you keep this up you may knock me off the seat as = president of=20 the dead stick club.
  I am now running rotors machined out to 3 mm seals and = at=20 about 400 hrs on them I can tell by checking through the exhaust = port that=20 the seal grooves are getting V'ed out and getting sloppy so I am = now=20 putting another engine together, on this one the rotors are in = prime shape=20 so I think I will run Tracy's 2mm seals.
 Also I think that the groves may be hardened and by = machining=20 the groves out makes them softer as they shouldn't have worn out = in only=20 400 hrs.
  Ken



Well, the=20 decision has been made.  Thanks in part to the wife's = continued=20 interest in my warm body on  cold winter nights, the = decision has=20 been made to purchase new rotors and rotor housings.  $$ = but=20 apparently I am worth it {:>)
 
I = looked into=20 milling out the slots to 3mm and that would have been the = cheaper=20 approach - but cheap approach is probably partly responsible for = me=20 being in this situation - so going to try a different approach = this=20 time.  Besides leery of using a rotor which clearly has = been=20 subjected to sufficient loads to scrape metal off its surface = and peen=20 over apex slot.
 
In the process=20 of getting quotes.
 
Ed
 
Ed=20 Anderson
Rv-6A N494BW Rotary Powered
Matthews, = NC
eanderson@carolina.rr.com
=

------=_NextPart_000_0020_01C54323.4400D9F0--