X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail22.syd.optusnet.com.au ([211.29.133.160] verified) by logan.com (CommuniGate Pro SMTP 5.0.6) with ESMTPS id 931880 for flyrotary@lancaironline.net; Wed, 18 Jan 2006 16:59:56 -0500 Received-SPF: none receiver=logan.com; client-ip=211.29.133.160; envelope-from=lendich@optusnet.com.au Received: from george (d220-236-170-90.dsl.nsw.optusnet.com.au [220.236.170.90]) by mail22.syd.optusnet.com.au (8.12.11/8.12.11) with SMTP id k0ILx0kK017428 for ; Thu, 19 Jan 2006 08:59:04 +1100 Message-ID: <001b01c61c7a$67b2b270$5aaaecdc@george> From: "george lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Auto fuel Date: Thu, 19 Jan 2006 07:59:06 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0018_01C61CCE.3851E650" 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 This is a multi-part message in MIME format. ------=_NextPart_000_0018_01C61CCE.3851E650 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Joe,=20 Thanks for the response - I need to qualify some points. There are about 4 resin ( as in epoxy resin) manufacturers in the world = - so the BASIC resin is pretty standard. I take you point, indeed there are different fillers and colours in = different resins, but this doesn't make such a big difference, but they = still have to matched to the hardener. The real difference is in the hardener. Hardeners are very complex, and = the more complex the more expensive. It could very well be the better = the hardener the better the molecule to molecule mix ( higher density?). = If This is true than Al's statement is true, but he hasn't said that - = WHAT HE IS SAYING isn't clearly defining these points and could be = misunderstood by others. I quite obviously have trouble with what he was = saying. George ( down under) George -=20 Al knows full well the strict ratios for epoxy reaction. He built and = is flying a Cozy. What he is saying is that epoxies that use a higher = resin to hardener ratio "TEND" to be more resilient to fuel & alcohol. = Al pointed out that this is coming from a couple of epoxy experts that = have been on the canard forums for years. An epoxy with an 80/20 or = 100/40 ratio "tend" to be more non-reactive. =20 Epoxy quality can't necessarily be defined by ratio - BUT - most = epoxies use the same basic chemicals and reactions (also pointed out by = the "epoxy experts"). So, "quality" is generally a matter of fillers, = colorants, etc. supplied by the mixer of the final product being sold. = Depends on the fillers used.=20 =20 Strength and chemical resistance are unrelated. I'm guessing there are = epoxies that are strong - but that will dissolve in fuel and/or alcohol. = So, strength is not the only criteria when selecting an epoxy. If one is = going to use epoxy in the fuel tank - that needs to be researched and = tested. =20 A couple of years ago I met the MGS epoxy representative for North = America. I asked him about fuel resistance. His basic answer was that = no epoxy company will tell you their epoxy is "fuel proof". That's = because they don't know what constitutes the word "fuel" - could be lots = of things including rocket fuel. His only firm answer was "I build a = composite plane 20 years ago with MGS and it's still flying today with = the same composite gas tanks". =20 Regards, Joe Hull Cozy Mk-IV #991 (preping for DAR inspection - details, details)=20 Redmond (Seattle), Washington =20 -------------------------------------------------------------------------= ----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] = On Behalf Of george lendich Sent: Wednesday, January 18, 2006 1:02 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Auto fuel =20 Al, Just so we are talking about the same thing here, I've asked some = questions in the body of your e-mail. No, I wasn't speaking of polyester. You can buy epoxies of different = ratios. I'm told by expert (Gary Hunter) that all epoxies which use = ratios like 80/20 have significantly better mechanical and chemical = properties.=20 =20 Better properties to what? 1. All epoxies uses strict ratios, as I explained! 2. The ratios are set by the manufacturers. 3. There are different quality Epoxy Resins - I agree, but the = quality can't be quantified by the ratio of the resin to hardener alone, = to my knowledge!=20 4. The dearer resins are quite obviously, better quality! 5. The Quality resins are those most often used in Aviation and = there is comprehensive information available on structural strength etc. 6. If someone where to use a cheap Epoxy without researching it's = properties - I would be very concerned. 7.Are you suggesting that people may use a cheaper (non structural) = resin to line fuel tanks and my therefore see a break-down of the = material sooner? =20 George (down under) =20 =20 This is measurable, and agrees with my and other peoples tests. Like = I say, I tested all of the fuel tank components in various batches of = alcohol fuel for years (you know how I don't like design assumptions). = None of the components were affected. The only exception was when I = exposed 50/50 epoxy mix to fuel. It slowly got mushy.=20 =20 I have seen fuel tanks destroyed, leaking like a sieve from exposure = to alcohol fuel. One reportedly had old version of proseal inside. It = completely peeled off tank inside. Clogged fuel port. Forced landing. If = memory serves me correct, it also had poly that degraded by erosion. It = looked like someone had etched the poly out of the tank.=20 =20 -al wick Artificial intelligence in cockpit, Cozy IV powered by stock Subaru = 2.5 N9032U 200+ hours on engine/airframe from Portland, Oregon Prop construct, Subaru install, Risk assessment, Glass panel design = info: http://www.maddyhome.com/canardpages/pages/alwick/index.html =20 On Wed, 18 Jan 2006 20:07:41 +1000 "george lendich" = writes: Al, You must be speaking about Polyester as Epoxy must absolutely = maintain a strict ration mix, as per manufacturers instructions, to = allow proper molecule to molecule bonding of the hardener and the resin. = Polyester on the other hand has flexibility in that, more hardener = promotes hardening sooner. George (down under) I tested the hell out of that. No effect. Years of exposure to = different batches of known alcohol. I understand that if you use a resin = of high proportions of hardener to resin, it's resistant. If you use = 50/50, it isn't. I had 50/50 get soft from fuel exposure. This info consistent with all the other guys that did the same = test. =20 -al wick Artificial intelligence in cockpit, Cozy IV powered by stock = Subaru 2.5 N9032U 200+ hours on engine/airframe from Portland, Oregon Prop construct, Subaru install, Risk assessment, Glass panel = design info: http://www.maddyhome.com/canardpages/pages/alwick/index.html On Tue, 17 Jan 2006 22:21:34 -0600 "William" = writes: It will make it less attractive for those with fiberglass = tanks. Alcohol/gas mixes are more aggressive than either gas or alcohol = alone. Bill Schertz KIS Cruiser # 4045 ----- Original Message -----=20 From: John Downing=20 To: Rotary motors in aircraft=20 Sent: Tuesday, January 17, 2006 8:17 PM Subject: [FlyRotary] Auto fuel =20 By the Farm Bureau Paper it is stated that Wisconsin has = passed a law that all 87 no lead will contain 10% alcohol and that nine = other states are considering it. It didn't mention the other no lead = grades. Here in Michigan it is under consideration at this time, and = there is a good chance it pass. Other than cutting the power some what, = is going to effect the operation of the rotary in some other way. JohnD =20 =20 -al wick Artificial intelligence in cockpit, Cozy IV powered by stock Subaru = 2.5 N9032U 200+ hours on engine/airframe from Portland, Oregon Prop construct, Subaru install, Risk assessment, Glass panel design = info: http://www.maddyhome.com/canardpages/pages/alwick/index.html ------=_NextPart_000_0018_01C61CCE.3851E650 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Joe,
Thanks for the response - I need = to qualify=20 some points.
 
There are about 4 resin ( as in epoxy = resin)=20 manufacturers in the world - so the BASIC resin is pretty = standard.
 
I take you point, indeed there are = different=20 fillers and colours in different resins, but this doesn't make such = a=20 big difference, but they still have to matched to the=20 hardener.
 
The real difference is in the hardener. = Hardeners=20 are very complex, and the more complex the more expensive. It could very = well be=20 the better the hardener the better the molecule to molecule mix ( higher = density?). If This is true than Al's statement is true, but he hasn't = said that=20 - WHAT HE IS SAYING isn't clearly = defining these=20 points and could be misunderstood by others. I quite obviously have = trouble with=20 what he was saying.
George ( down under)

George =96=20

Al knows = full well=20 the strict ratios for epoxy reaction. He built and is flying a Cozy. = What he=20 is saying is that epoxies that use a higher resin to hardener ratio = =93TEND=94 to=20 be more resilient to fuel & alcohol. Al pointed out that this is = coming=20 from a couple of epoxy experts that have been on the canard forums for = years.=20 An epoxy with an 80/20 or 100/40 ratio =93tend=94 to be more=20 non-reactive.

 

Epoxy = quality can=92t=20 necessarily be defined by ratio =96 BUT =96 most epoxies use the same = basic=20 chemicals and reactions (also pointed out by the =93epoxy experts=94). = So,=20 =93quality=94 is generally a matter of fillers, colorants, etc. = supplied by the=20 mixer of the final product being sold. Depends on the fillers used.=20

 

Strength = and chemical=20 resistance are unrelated. I=92m guessing there are epoxies that are = strong =96 but=20 that will dissolve in fuel and/or alcohol. So, strength is not the = only=20 criteria when selecting an epoxy. If one is going to use epoxy in the = fuel=20 tank =96 that needs to be researched and = tested.

 

A couple of = years ago=20 I met the MGS epoxy representative for North=20 America.  I asked him about fuel resistance. His = basic answer=20 was that no epoxy company will tell you their epoxy is =93fuel = proof=94. That=92s=20 because they don=92t know what constitutes the word =93fuel=94 =96 = could be lots of=20 things including rocket fuel.  His only firm answer was =93I = build a=20 composite plane 20 years ago with MGS and it=92s still flying today = with the=20 same composite gas tanks=94.

 

Regards,

Joe = Hull

Cozy Mk-IV #991 (preping for = DAR=20 inspection - details, details)

Redmond (Seattle), Washington

 

From:=20 Rotary motors in aircraft = [mailto:flyrotary@lancaironline.net] On=20 Behalf Of george lendich
Sent: Wednesday, January 18, = 2006 1:02=20 PM
To: = Rotary motors in aircraft
Subject: [FlyRotary] Re: Auto=20 fuel

 

Al,

Just so we are talking = about the=20 same thing here, I've asked some questions in the body of your=20 e-mail.

No, I wasn't speaking of polyester. You can = buy=20 epoxies of different ratios. I'm told by expert (Gary Hunter) that all = epoxies=20 which use ratios like 80/20 have significantly better mechanical and = chemical=20 properties.

 

Better = properties to=20 what?

1. All epoxies uses strict = ratios, as I=20 explained!

2. The ratios are set by the=20 manufacturers.

3. There are different quality = Epoxy=20 Resins - I agree, but the quality can't be quantified by the ratio = of the=20 resin to hardener alone, to my=20 knowledge! 

4. The dearer resins are quite = obviously, better quality!

5. The Quality resins are = those most=20 often used in Aviation and there is comprehensive information = available=20 on structural strength etc.

6. If someone where to use a=20 cheap Epoxy without researching it's properties - I would be = very=20 concerned.

7.Are you suggesting that = people may use=20 a cheaper (non structural) resin to line fuel tanks and my therefore = see a=20 break-down of the material = sooner?

 

George (down=20 under)

 

 

This is measurable, and agrees with my and = other=20 peoples tests. Like I say, I tested all of the fuel tank=20 components in various batches of alcohol fuel for years (you = know how I=20 don't like design assumptions). None of the components were = affected. The=20 only exception was when I exposed 50/50 epoxy mix to fuel. It slowly = got=20 mushy.

 

I have seen fuel tanks destroyed, leaking = like a=20 sieve from exposure to alcohol fuel. One reportedly had old version = of=20 proseal inside. It completely peeled off tank inside. Clogged fuel = port.=20 Forced landing. If memory serves me correct, it also had poly = that=20 degraded by erosion. It looked like someone had etched the poly out = of the=20 tank.

 


-al wick
Artificial intelligence in = cockpit,=20 Cozy IV powered by stock Subaru 2.5
N9032U 200+ hours on = engine/airframe=20 from Portland,=20 Oregon
Prop = construct,=20 Subaru install, Risk assessment, Glass panel design info:
htt= p://www.maddyhome.com/canardpages/pages/alwick/index.html<= /SPAN>

 

On Wed, 18 Jan 2006 20:07:41 +1000 "george = lendich"=20 <lendich@optusnet.com.au>=20 writes:

Al,

You must be speaking = about=20 Polyester as Epoxy must absolutely maintain a strict ration mix, = as=20 per manufacturers instructions, to allow proper molecule = to=20 molecule bonding of the hardener and the resin. Polyester on = the=20 other hand has flexibility in that, more hardener promotes = hardening=20 sooner.

George (down=20 under)

I tested the hell out of that. No = effect. Years=20 of exposure to different batches of known alcohol. I understand = that if=20 you use a resin of high proportions of hardener to resin, it's=20 resistant. If you use 50/50, it isn't. I had 50/50 get soft from = fuel=20 exposure.

This info consistent with all the = other guys=20 that did the same test.

 


-al wick
Artificial = intelligence in=20 cockpit, Cozy IV powered by stock Subaru 2.5
N9032U 200+ = hours on=20 engine/airframe from Portland, Oregon
Prop construct, = Subaru=20 install, Risk assessment, Glass panel design=20 = info:
http://www.maddyhome.com/canardpages/pages/alwick/index.html

On Tue, 17 Jan 2006 22:21:34 -0600 = "William"=20 <wschertz@ispwest.com>=20 writes:

It will make it = less=20 attractive for those with fiberglass tanks. Alcohol/gas mixes = are more=20 aggressive than either gas or alcohol=20 alone.

Bill Schertz
KIS Cruiser #=20 4045

----- Original = Message=20 -----

From:=20 John Downing=20

Sent:=20 Tuesday, January 17, 2006 8:17 = PM

Subject:=20 [FlyRotary] Auto fuel

 

By the Farm = Bureau Paper=20 it is stated that Wisconsin has passed a = law that=20 all 87 no lead will contain 10% alcohol and that nine other = states=20 are considering it.  It didn't mention the other no = lead=20 grades.  Here in Michigan it is under = consideration=20 at this time, and there is a good chance it pass.  = Other than=20 cutting the power some what, is going to effect the = operation of the=20 rotary in some other way. =20 JohnD

 

=

 


-al wick
Artificial intelligence in = cockpit,=20 Cozy IV powered by stock Subaru 2.5
N9032U 200+ hours on = engine/airframe=20 from Portland,=20 Oregon
Prop = construct,=20 Subaru install, Risk assessment, Glass panel design=20 = info:
http://www.maddyhome.com/canardpages/pages/alwick/index.html

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