Return-Path: Received: from ms-smtp-01.southeast.rr.com ([24.93.67.82] verified) by logan.com (CommuniGate Pro SMTP 4.1.4) with ESMTP id 2605155 for flyrotary@lancaironline.net; Fri, 26 Sep 2003 14:30:27 -0400 Received: from o7y6b5 (clt78-020.carolina.rr.com [24.93.78.20]) by ms-smtp-01.southeast.rr.com (8.12.5/8.12.2) with SMTP id h8QIMoA8000993 for ; Fri, 26 Sep 2003 14:22:52 -0400 (EDT) Message-ID: <001001c3845b$e2658420$1702a8c0@WorkGroup> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] aluminum intake tubing? Date: Fri, 26 Sep 2003 14:27:46 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_000D_01C3843A.5B10C0A0" 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_000D_01C3843A.5B10C0A0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MessageHi Rusty, I presume you want them pre-bent? If not you must anneal? the = tubing to "O" (soft) condition prior to bending. Otherwise, you will = surely end up with cracks. Then you can have the heat treated back to = the 6061 T3/6 condition. =20 If you order from Burns and bent tubing, you will get it in the "O" = condition or a slightly harder condition due to the cold work hardening = from bending. I found that heating them at 500F for 8 hours seems to = harden them a bit - they don't ding as easily as the "O" condition. For intake runners, I generally use 1 3/8" OD 0.058 or .065 wall = thickness for the primary. I use 1 5/8" OD same wall thickness for = secondaries. I have used from 1 1/4" to 1 3/4" but I think the other = diameters are about optimum. Its all 6061 from Burns. You can use 6063 = (architecture aluminm alloy - a bit more corrosion resistant - but hard = to find in bends. You can get the Burn's lengths and then added to the lenght. You can do = it by adding a short length (2"?) of the next larger diameter size as a = coupler so that both ends fit inside. However, its difficult to find a = welder that can weld thin tubing. I have had good success with brazing = the thin wall stuff. There are a couple of other places for bent tubing, but their = "tangents" as they call the length before and after the bend are even = shorter and the walls much thicker - almost like pipes. You can get pipe bends (Elbows) from RBWagner schedule 40 which has = walls of approx 0.12 ". It is much heavier but you can use it just for = the bend and then stick in straight light weight tubes from most of = your runner lenght. Just a few options. Me, I am currently making the mold for another = plastic intake part. This time it will be for the lower part of the = intake, so I can use inexpensive straight tubing with the bend in the = plastic casting rather than keep paying for expensive pre-bent tubing. Good Luck Ed Anderon ----- Original Message -----=20 From: Russell Duffy=20 To: Rotary motors in aircraft=20 Sent: Friday, September 26, 2003 1:35 PM Subject: [FlyRotary] aluminum intake tubing? Ed (or anyone else),=20 Where's the best place to get aluminum tubing for intake runners. = What alloy, and wall thickness is most common? Burns has 6061 with a = 90 degree bend, but the legs are only 4" and 12" long, which won't be = quite long enough. Has anyone had good luck bending this size tubing = yourself? =20 Thanks, Rusty ------=_NextPart_000_000D_01C3843A.5B10C0A0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Message
Hi Rusty,
 
    I presume you want = them=20 pre-bent?  If not you must anneal? the tubing to "O" (soft) = condition prior=20 to bending.  Otherwise, you will surely end up with cracks.  = Then you=20 can have the heat treated back to the 6061 T3/6 condition.  =
 
   If you order from Burns = and bent=20 tubing, you will get it in the "O" condition or a slightly harder = condition due=20 to the cold work hardening from bending.  I found that heating them = at 500F=20 for 8 hours seems to harden them a bit - they don't ding as easily as = the "O"=20 condition.
 
For intake runners, I generally use 1 = 3/8" OD 0.058=20 or .065 wall thickness for the primary.  I use 1 5/8" OD same = wall=20 thickness  for secondaries.  I have used from 1 1/4" to 1 3/4" = but I=20 think the other diameters are about optimum.  Its all 6061 from=20 Burns.  You can use 6063 (architecture aluminm alloy - a bit more = corrosion=20 resistant - but hard to find in bends.
 
You can get the Burn's lengths and then = added to=20 the lenght.  You can do it by adding a short length (2"?) of the = next=20 larger diameter size as a coupler so that both ends fit inside.  = However,=20 its difficult to find a welder that can weld thin tubing.  I have = had good=20 success with brazing the thin wall stuff.
 
 There are a couple of other = places for bent=20 tubing, but their  "tangents" as they call the length before and = after the=20 bend are even shorter and the walls much thicker - almost like=20 pipes.
 
You can get pipe bends = (Elbows) from=20 RBWagner schedule 40 which has walls of approx 0.12 ".  It is much = heavier=20 but you can use it just for the bend and then stick in straight light = weight=20 tubes from  most of your runner lenght.
 
Just a few options.  Me, I am = currently making=20 the mold for another plastic intake part.  This time it will be for = the=20 lower part of the intake, so I can use inexpensive straight tubing with = the bend=20 in the plastic casting rather than keep paying for expensive pre-bent=20 tubing.
 
Good Luck
 
Ed Anderon
----- Original Message -----
From:=20 Russell=20 Duffy
Sent: Friday, September 26, = 2003 1:35=20 PM
Subject: [FlyRotary] aluminum = intake=20 tubing?

Ed (or anyone = else),=20
 
Where's the = best place to=20 get aluminum tubing for intake runners.  What alloy, and wall = thickness=20 is most common?   Burns has 6061 with a 90 degree bend, but = the legs=20 are only 4" and 12" long, which won't be quite long = enough.   Has=20 anyone had good luck bending this size tubing yourself? =20
 
Thanks,
Rusty
 
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