X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from proton.sasknet.sk.ca ([142.165.20.178] verified) by logan.com (CommuniGate Pro SMTP 5.4c3j) with ESMTPS id 4990545 for flyrotary@lancaironline.net; Sat, 21 May 2011 12:47:33 -0400 Received-SPF: none receiver=logan.com; client-ip=142.165.20.178; envelope-from=hjjohnson@sasktel.net Received: from pps.filterd (proton [127.0.0.1]) by proton.sasknet.sk.ca (8.14.3/8.14.3) with SMTP id p4LGhfk0022221 for ; Sat, 21 May 2011 10:46:56 -0600 Received: from bgmpomr1.sasknet.sk.ca (bgmpOMR1.sasknet.sk.ca [142.165.72.22]) by proton.sasknet.sk.ca with ESMTP id weh4405t1-1 for ; Sat, 21 May 2011 10:46:56 -0600 Received: from sasktel.net ([192.168.234.97]) by bgmpomr1.sasknet.sk.ca (SaskTel eMessaging Service) with ESMTP id <0LLK0074C1A8O130@bgmpomr1.sasknet.sk.ca> for flyrotary@lancaironline.net; Sat, 21 May 2011 10:46:56 -0600 (CST) Received: from [192.168.234.25] (Forwarded-For: [98.125.90.150]) by cgmail1.sasknet.sk.ca (mshttpd); Sat, 21 May 2011 10:46:56 -0600 Date: Sat, 21 May 2011 10:46:56 -0600 From: H & J Johnson Subject: Re: [FlyRotary] Re: Blower experiment: FAIL To: Rotary motors in aircraft Message-id: <81f5b5e9d465.4dd79820@sasktel.net> MIME-version: 1.0 X-Mailer: Sun Java(tm) System Messenger Express 6.1 HotFix 0.20 (built Feb 27 2006) Content-type: text/plain; charset=us-ascii Content-language: en Content-transfer-encoding: 7BIT Content-disposition: inline X-Accept-Language: en Priority: normal X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.4.6813,1.0.148,0.0.0000 definitions=2011-05-21_03:2011-05-20,2011-05-21,1970-01-01 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=default score=0 spamscore=0 ipscore=0 suspectscore=0 phishscore=0 bulkscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx engine=5.0.0-1012030000 definitions=main-1105210072 No question riveted would see the highest point load levels. Anyway, Cast would/should work. It would need to be balanced the same as any other. Billet has the potential of being fairly pricey. I'm assuming that aluminum would be the prefered [I'll have to look up which alloy is best for something with high cyclical loads. Are you thinking you'd want one w/ a top ring or just a open face fan unit [like a turbo impeller]? If we go cast, it is possible to put in a top ring which would help hold the blades at their top/outter edge w/ a billet unit it would be 'possible' but very costly to machine in the top ring. I'm not back to the office until Tuesday but I can get the details ready to get pricing together. Jarrett Johnson www.innovention-tech.com ----- Original Message ----- From: Ernest Christley Date: Friday, May 20, 2011 6:43 pm Subject: [FlyRotary] Re: Blower experiment: FAIL > On 05/20/2011 07:35 PM, H & J Johnson wrote: > > So your thinking that the centrifugal forces are what sheared > the rivets? It's pretty crazy how high the forces spikes could be > from an unblanced fan. I've not see one yet that was just built > and installed w/out being balanced and lived for any period of > time. That kind of stuff fails spectacularly, once it starts to go > you couldn't stop it fast enough to stop it from exploding. > > Can't argue one way or the other. All I know is that it came > apart > completely, and I wouldn't trust another constructed that way to > last > any longer. > > > As far as cnc'ing one, sure that can be arranged. Are we talking > from billet or a casting or..? Material? > Would a cast object be able to hold together? I was thinking that > with > a CNC, a machined billet one-off would be the easiest route. > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html