X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [24.25.9.101] (HELO ms-smtp-02-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 5.0c3) with ESMTP id 750157 for flyrotary@lancaironline.net; Tue, 04 Oct 2005 23:44:31 -0400 Received-SPF: pass receiver=logan.com; client-ip=24.25.9.101; envelope-from=eanderson@carolina.rr.com Received: from edward2 (cpe-024-074-025-165.carolina.res.rr.com [24.74.25.165]) by ms-smtp-02-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id j953hil9018973 for ; Tue, 4 Oct 2005 23:43:45 -0400 (EDT) Message-ID: <001101c5c95e$c29fab80$2402a8c0@edward2> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: counterweights Date: Tue, 4 Oct 2005 23:42:07 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_000E_01C5C93D.3B54FA20" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_000E_01C5C93D.3B54FA20 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Ok, just a thought. The 8.4 could have the same depth of the 9.1 = provided the area of the depression was a bit larger. Could pour water = into the depression until its full and then do the same for a 9.1 {:>) = and compare. Yes, I don't know of any markings on the counterweights = that could be used to sort it out. =20 Well, I could believe 89-95 would have the same counterweights as those = rotors all supposedly weight the same 9.54 lbs regardless of the = compression (Humm a bit suspect there), but I would think the heavier = 10.4 lbs weights of the 86-88 would require heavier counterweights. Its a bitch when you don't get what you ordered and what's more have = little to go by to prove it one way or the other. Me? I'm Waiting for new right-gear leg. After replacing the clearly = bent left gear which had my left wing tip 3" lower than the right, I = found that after replacing that gear leg, that the left wing is now 6" = higher than the right one. Taking the right gear leg off and using a = straight edge, I found the lower axle area about 3" to the rear of where = it should be. Result of my hard landing back in Feb when I found out = that pulling the power all the way to idle made my 76x88 prop act like a = very effective airbrake. The excursion into the ditch when the = brakeline blew in June didn't help any I'm certain. But, hope to get it all back together for Shady Bend in October. Ed A =20 =20 Thanks Ed, but that wont work. =20 I only have 1 rear counter weight, and that came with the engine sold = to me by Adkins (the other engine came with a flywheel). Turns out the = rotors in that engine were 8.5:1 S4 turbo rotors when they were supposed = to be the S5 turbo rotors. So I have absolutely no faith in what kind = of counter weights he threw on there. There is one for sale on e-bay - = but that guy does not know what year it came from either. hmmm=20 To throw a wrench in the works, I was reading about the subject on the = RX-7 forum, and one guy claims that has weighed the counter weights and = finds that all engines from 86-95 have the same counter weights!! But I = want to believe it because it would be easy.=20 I know that Mazda has different part numbers but I suppose they could = still all be the same... Sigh..... =20 And the worst part is that there was a pair of 9.7:1 rotors on e-bay a = while back and I flaked and forgot to put in a bit... they went for = $120 for the pair, but new ones are $600 each - ouch! I'm taking a good hard look at trying to repair the 9.4 rotors that = Ernest sent... Thanks for all the great stats to help me identify the rotors. The = depth seems to match everything else I know about the rotors. Except: The depth of the chamber on the rotors from Atkins (10.2# with cast = depression) is only (about) 7 mm. Do you think that the 8.5 rotors = might have the same depth as the 9.0 (or 9.1) rotors? Dave =20 On 10/4/05, Ed Anderson wrote:=20 Dave, a though occurred to me. Since you do know the weight of the = rotors for each compression and year (see Mazdatirx chart below), if = any one had the counter weights for a know year, I imagine there is a = proportional ratio between rotor weight and counter weight. In other = words, the lightest rotors should take the lightest counter weights. = Heaviest rotors the heaviest counterweights. In fact if you had two = data points for two different compression rotors you could probably come = close to figuring out the third counter weight weight.=20 Just a though. Ed A Engine Year Compression Weight (Grams) Weight (Pounds)=20 12A 76-82 9.4 4603 10.15=20 12A 83-85 9.4 4353 9.60=20 13B 74-78 9.2 5253 11.58=20 13B 84-85 9.4 5253 11.58=20 13B N/T 86-88 9.4 4553 10.04=20 13B Turbo 86-88 8.5 4553 10.04=20 13B N/T 89-92 9.7 4328 9.54=20 13B Turbo 89-92 9.0 4328 9.54=20 13B T/T 93-95 9.0 4328 9.54=20 Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com=20 --=20 Dave Leonard Turbo Rotary RV-6 N4VY http://members.aol.com/_ht_a/rotaryroster/index.html=20 http://members.aol.com/_ht_a/vp4skydoc/index.html ------=_NextPart_000_000E_01C5C93D.3B54FA20 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Ok, just a thought.   The 8.4 could = have the=20 same depth of the 9.1 provided the area of the depression was a bit=20 larger.  Could pour water into the depression until its full and = then do=20 the same for a 9.1 {:>) and compare.  Yes, I don't know of any = markings=20 on the counterweights that could be used to sort it out.  =
 
Well, I could believe 89-95 would have the same=20 counterweights as those rotors all supposedly weight the same 9.54 lbs=20 regardless of the compression (Humm a bit suspect there), but I would = think the=20 heavier 10.4 lbs weights of the 86-88 would require heavier=20 counterweights.
 
Its a bitch when you don't get what you ordered = and what's=20 more have little to go by to prove it one way or the other.
 
Me? I'm Waiting for new right-gear leg.  = After=20 replacing the clearly bent left gear which had my left wing tip 3" lower = than=20 the right, I found that after replacing that gear leg, that the left = wing is now=20 6" higher than the right one.  Taking the right gear = leg off and=20 using a straight edge, I found the lower axle area about 3" to the rear = of where=20 it should be.  Result of my hard landing back in Feb when I found = out that=20 pulling the power all the way to idle made my 76x88 prop act like a very = effective airbrake.  The excursion into the ditch when the = brakeline blew=20 in June didn't help any I'm certain.
 
But, hope to get it all back together for Shady = Bend in=20 October.
 
 
Ed A
 
 
Thanks Ed, but that wont work. 
 
I only have 1 rear counter weight, and that came with the = engine=20 sold to me by Adkins (the other engine came with a flywheel).  = Turns out=20 the rotors in that engine were 8.5:1 S4 turbo rotors when they were = supposed=20 to be the S5 turbo rotors.  So I have absolutely no faith in what = kind of=20 counter weights he threw on there.  There is one for sale on = e-bay - but=20 that guy does not know what year it came from either.  hmmm =
 
To throw a wrench in the works, I was reading about the subject = on the=20 RX-7 forum, and one guy claims that has weighed the counter weights = and finds=20 that all engines from 86-95 have the same counter weights!!  But = I want=20 to believe it because it would be easy.
 
I know that Mazda has different part numbers but I suppose they = could=20 still all be the same...
 
Sigh..... 
 
And the worst part is that there was a pair of 9.7:1 rotors on = e-bay a=20 while back and I flaked and forgot to put in a bit...  they went = for $120=20 for the pair, but new ones are $600 each - ouch!
 
I'm taking a good hard look at trying to repair the 9.4 rotors = that=20 Ernest sent...
 
Thanks for all the great stats to help me identify the = rotors.  The=20 depth seems to match everything else I know about the rotors. =20 Except:
 
The depth of the chamber on the rotors from Atkins (10.2#  = with cast=20 depression) is only (about) 7 mm.  Do you think that = the 8.5=20 rotors might have the same depth as the 9.0 (or 9.1) rotors?
 
Dave

 
On 10/4/05, Ed=20 Anderson <eanderson@carolina.rr.com&g= t;=20 wrote:=20
Dave, a though occurred to me.  Since = you do know=20 the weight of the rotors for each compression and year (see = Mazdatirx chart=20 below), if  any one had the counter weights for a know year, I = imagine=20 there is a proportional ratio between rotor weight and counter = weight. =20 In other words, the lightest rotors should take the lightest counter = weights.  Heaviest rotors the heaviest counterweights.  In = fact if=20 you had two data points for two different compression rotors you = could=20 probably come close to figuring out the third counter weight weight. =
 
Just a though.
 
Ed A
=
Engine Year Compression Weight (Grams) Weight (Pounds)
12A 76-82 9.4 4603 10.15
12A 83-85 9.4 4353 9.60
13B 74-78 9.2 5253 11.58
13B 84-85 9.4 5253 11.58
13B N/T 86-88 9.4 4553 10.04
13B Turbo 86-88 8.5 4553 10.04
13B N/T 89-92 9.7 4328 9.54
13B Turbo 89-92 9.0 4328 9.54
13B T/T 93-95 9.0 43289.54
 
 
Ed Anderson
Rv-6A N494BW Rotary=20 Powered
Matthews, NC
eanderson@carolina.rr.com=20



-- =
Dave=20 Leonard
Turbo Rotary RV-6 N4VY
http://memb= ers.aol.com/_ht_a/rotaryroster/index.html=20
http://members= .aol.com/_ht_a/vp4skydoc/index.html=20 ------=_NextPart_000_000E_01C5C93D.3B54FA20--