Return-Path: Sender: (Marvin Kaye) To: flyrotary Date: Mon, 02 Jun 2003 09:03:38 -0400 Message-ID: X-Original-Return-Path: Received: from bewersdorff.com ([192.220.83.90] verified) by logan.com (CommuniGate Pro SMTP 4.1b6) with SMTP id 2371223 for flyrotary@lancaironline.net; Mon, 02 Jun 2003 02:31:33 -0400 Received: (qmail 67507 invoked by uid 21338); 2 Jun 2003 06:31:18 -0000 Received: from unknown (HELO rapunzel) ([216.101.149.124]) (envelope-sender ) by 192.220.83.90 (qmail-ldap-1.03) with SMTP for ; 2 Jun 2003 06:31:18 -0000 From: "Marko Bewersdorff" X-Original-To: "Rotary motors in aircraft" Subject: electric vacuum pump - a way unscientific science experiment X-Original-Date: Sun, 1 Jun 2003 23:30:14 -0700 X-Original-Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) In-Reply-To: X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 Importance: Normal I just toyed with an electrically driven vacuum pump for the instruments. Trial one and two: A like new vacuum pump operated at by a big drill press (1.5 HP): 2100 RPM resulted in enough vacuum to run the attitude gyro at minimum suction on the gage (4.5 "Hg. at sea level - so not enough at altitude.) 2500 RPM - the next belt setting - resulted briefly in enough vacuum - I think - and then the unlabeled breaker in my surge protector popped. Trial three: 12 Volt electric motor from the surplus place, 1 3/4 " O.D. by 2 1/2 " long permanent magnet like the biggest I have ever seen in a model boat. Hooked it up to a 12 Volt battery, burnt my finger with the wire going to it - didn't get up to RPM anyways - smelled like amps. Conclusion: Rats, I'm thinking electric gyros now. regards Marko Bewersdorff Rotary Long EZ in the works.