X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imr-ma03.mx.aol.com ([64.12.206.41] verified) by logan.com (CommuniGate Pro SMTP 5.4.0) with ESMTP id 5071947 for flyrotary@lancaironline.net; Tue, 02 Aug 2011 16:27:49 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.12.206.41; envelope-from=wrjjrs@aol.com Received: from mtaout-ma01.r1000.mx.aol.com (mtaout-ma01.r1000.mx.aol.com [172.29.41.1]) by imr-ma03.mx.aol.com (8.14.1/8.14.1) with ESMTP id p72KR2TZ005753 for ; Tue, 2 Aug 2011 16:27:02 -0400 Received: from [10.241.225.123] (113.sub-174-253-233.myvzw.com [174.253.233.113]) (using TLSv1 with cipher RC4-MD5 (128/128 bits)) (No client certificate requested) by mtaout-ma01.r1000.mx.aol.com (MUA/Third Party Client Interface) with ESMTPSA id 8CD1EE00011F for ; Tue, 2 Aug 2011 16:26:57 -0400 (EDT) Message-ID: From: "wrjjrs@aol.com" To: "Rotary motors in aircraft" Date: Tue, 2 Aug 2011 13:27:12 -0700 X-Mailer: Motorola android mail 1.0 MIME-Version: 1.0 Subject: Re: [FlyRotary] Re: Flywheel Machine Work X-Priority: 3 References: In-Reply-To: Content-Type: multipart/alternative; boundary="Motorola-A-Mail-ChiIv2lCZ39zVsNq" x-aol-global-disposition: G X-AOL-SCOLL-SCORE: 0:2:434165440:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d29014e385d915667 X-AOL-IP: 174.253.233.113 --Motorola-A-Mail-ChiIv2lCZ39zVsNq Content-Type: text/plain; Format="Flowed"; DelSp="Yes"; charset="US-ASCII" Content-Transfer-Encoding: 7bit Dale, I think you got a term wrong there. I get 807.34 rpm @ 60 mph. 25" x 3.14=78.53in 78.53/12=6.54ft. 60mph=1mile per minute. 5280'/6.545=807.34 RPM Bill Jepson Connected by DROID on Verizon Wireless -----Original message----- From: Dale_R To: Rotary motors in aircraft Sent: Tue, Aug 2, 2011 18:02:27 GMT+00:00 Subject: [FlyRotary] Re: Flywheel Machine Work On 8/2/2011 5:05 AM, David Leonard wrote: > ... I am starting to think that the whole science of balancing is > just a gimmick. Despite the old balance hole being mostly drilled > away, the new balance holes are on the opposite side of the flywheel. !?? > Dave, Balancing is a procedure that falls right on the edge between science and black art. At high RPMs, changes "out of plane" can become critical. As an example, when I started balancing wheels all we had were bubble (static) balancers, and - because the weights had to go on the rim edges - we would find the amount of weight, then split it, e.g. two half ounce weights, one on the inside and one on the outside. ~Most~ of the time it would put give good freeway speed balance. Sometimes, though, we'd still get an out-of-balance wobble in the wheel due to the imbalance being off center of the c.g. plane of the wheel. Then affordable (for a small shop) dynamic balancers came along, and we discovered that, most of the time, less weight was required on one side of the wheel than the other, often not even opposite each other, to bring the center of balance the same as the center of rotation. Drilling balance divots on only one side of something like a wheel can create a similar situation - where the static balance is correct but the center of balance is no longer the same as the center of rotation. It takes sophisticated equipment and an equally sharp operator to get it right. BTW, FWIW ... For an average car tire with 25" diameter at the tread, at 60 MPH, the wheel is turning ~7950 RPM. -- Dale_R Cozy MKIV #497 -- Homepage: http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html --Motorola-A-Mail-ChiIv2lCZ39zVsNq Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: base64 PGh0bWw+PGhlYWQ+PHN0eWxlIHR5cGU9InRleHQvY3NzIj5ib2R5IHt3b3JkLXdyYXA6IGJyZWFr LXdvcmQ7IGJhY2tncm91bmQtY29sb3I6I2ZmZmZmZjt9PC9zdHlsZT48L2hlYWQ+PGJvZHk+PGRp diBzdHlsZT0iZm9udC1mYW1pbHk6IHNhbnMtc2VyaWY7IGZvbnQtc2l6ZTogMTZweCI+RGFsZSw8 YnI+SSB0aGluayB5b3UgZ290IGEgdGVybSB3cm9uZyB0aGVyZS4gSSBnZXQgPGEgaHJlZj0idGVs OjgwNzM0Ij44MDcuMzQ8L2E+IHJwbSBAIDYwIG1waC4gMjUiIHggMy4xND03OC41M2luPGJyPjc4 LjUzLzEyPTYuNTRmdC4gNjBtcGg9MW1pbGUgcGVyIG1pbnV0ZS4gNTI4MCcvNi41NDU9PGEgaHJl Zj0idGVsOjgwNzM0Ij44MDcuMzQ8L2E+IFJQTTxicj5CaWxsIEplcHNvbjxicj48YnI+PGZvbnQg Y29sb3I9IiMzMzMzMzMiPjxpPjxzcGFuIHN0eWxlPSJmb250LXNpemU6IDE0cHgiPjxmb250IGZh Y2U9InNhbnMtc2VyaWYiPkNvbm5lY3RlZCBieSBEUk9JRCBvbiBWZXJpem9uIFdpcmVsZXNzPC9m b250Pjwvc3Bhbj48L2k+PC9mb250PjwvZGl2Pjxicj48YnI+LS0tLS1PcmlnaW5hbCBtZXNzYWdl LS0tLS08YnI+PGJsb2NrcXVvdGUgc3R5bGU9IjsgYm9yZGVyLWxlZnQ6IDJweCBzb2xpZCByZ2Io MTYsIDE2LCAyNTUpOyBtYXJnaW4tbGVmdDogNXB4OyBwYWRkaW5nLWxlZnQ6IDVweDsiPjxkaXYg c3R5bGU9ImZvbnQtZmFtaWx5OiBzYW5zLXNlcmlmOyBmb250LXNpemU6IDE0cHgiPjxiPkZyb206 IDwvYj5EYWxlX1IgJmx0O2RhbGUucm9nQGdtYWlsLmNvbSZndDs8Yj48YnI+VG86IDwvYj5Sb3Rh cnkgbW90b3JzIGluIGFpcmNyYWZ0ICZsdDtmbHlyb3RhcnlAbGFuY2Fpcm9ubGluZS5uZXQmZ3Q7 PGI+PGJyPlNlbnQ6IDwvYj5UdWUsIEF1ZyAyLCAyMDExIDE4OjAyOjI3IEdNVCswMDowMDxiPjxi cj5TdWJqZWN0OiA8L2I+W0ZseVJvdGFyeV0gUmU6IEZseXdoZWVsIE1hY2hpbmUgV29yazxicj48 YnI+PC9kaXY+T24gOC8yLzIwMTEgNTowNSBBTSwgRGF2aWQgTGVvbmFyZCB3cm90ZTo8YnI+PiAu Li4gIEkgYW0gc3RhcnRpbmcgdG8gdGhpbmsgdGhhdCB0aGUgd2hvbGUgc2NpZW5jZSBvZiBiYWxh bmNpbmcgaXMgPGJyPj4ganVzdCBhIGdpbW1pY2suICBEZXNwaXRlIHRoZSBvbGQgYmFsYW5jZSBo b2xlIGJlaW5nIG1vc3RseSBkcmlsbGVkIDxicj4+IGF3YXksIHRoZSBuZXcgYmFsYW5jZSBob2xl cyBhcmUgb24gdGhlIG9wcG9zaXRlIHNpZGUgb2YgdGhlIGZseXdoZWVsLiAhPz88YnI+Pjxicj48 YnI+RGF2ZSw8YnI+PGJyPiAgICBCYWxhbmNpbmcgaXMgYSBwcm9jZWR1cmUgdGhhdCBmYWxscyBy aWdodCBvbiB0aGUgZWRnZSBiZXR3ZWVuIDxicj5zY2llbmNlIGFuZCBibGFjayBhcnQuICBBdCBo aWdoIFJQTXMsIGNoYW5nZXMgIm91dCBvZiBwbGFuZSIgY2FuIGJlY29tZSA8YnI+Y3JpdGljYWwu PGJyPjxicj4gICAgQXMgYW4gZXhhbXBsZSwgd2hlbiBJIHN0YXJ0ZWQgYmFsYW5jaW5nIHdoZWVs cyBhbGwgd2UgaGFkIHdlcmUgPGJyPmJ1YmJsZSAoc3RhdGljKSBiYWxhbmNlcnMsIGFuZCAtIGJl Y2F1c2UgdGhlIHdlaWdodHMgaGFkIHRvIGdvIG9uIHRoZSA8YnI+cmltIGVkZ2VzIC0gd2Ugd291 bGQgZmluZCB0aGUgYW1vdW50IG9mIHdlaWdodCwgdGhlbiBzcGxpdCBpdCwgZS5nLiB0d28gPGJy PmhhbGYgb3VuY2Ugd2VpZ2h0cywgb25lIG9uIHRoZSBpbnNpZGUgYW5kIG9uZSBvbiB0aGUgb3V0 c2lkZS4gIH5Nb3N0fiBvZiA8YnI+dGhlIHRpbWUgaXQgd291bGQgcHV0IGdpdmUgZ29vZCBmcmVl d2F5IHNwZWVkIGJhbGFuY2UuICBTb21ldGltZXMsIDxicj50aG91Z2gsIHdlJ2Qgc3RpbGwgZ2V0 IGFuIG91dC1vZi1iYWxhbmNlIHdvYmJsZSBpbiB0aGUgd2hlZWwgZHVlIHRvIHRoZSA8YnI+aW1i YWxhbmNlIGJlaW5nIG9mZiBjZW50ZXIgb2YgdGhlIGMuZy4gcGxhbmUgb2YgdGhlIHdoZWVsLjxi cj48YnI+ICAgIFRoZW4gYWZmb3JkYWJsZSAoZm9yIGEgc21hbGwgc2hvcCkgZHluYW1pYyBiYWxh bmNlcnMgY2FtZSBhbG9uZywgYW5kIDxicj53ZSBkaXNjb3ZlcmVkIHRoYXQsIG1vc3Qgb2YgdGhl IHRpbWUsIGxlc3Mgd2VpZ2h0IHdhcyByZXF1aXJlZCBvbiBvbmUgPGJyPnNpZGUgb2YgdGhlIHdo ZWVsIHRoYW4gdGhlIG90aGVyLCBvZnRlbiBub3QgZXZlbiBvcHBvc2l0ZSBlYWNoIG90aGVyLCB0 byA8YnI+YnJpbmcgdGhlIGNlbnRlciBvZiBiYWxhbmNlIHRoZSBzYW1lIGFzIHRoZSBjZW50ZXIg b2Ygcm90YXRpb24uPGJyPjxicj4gICAgRHJpbGxpbmcgYmFsYW5jZSBkaXZvdHMgb24gb25seSBv bmUgc2lkZSBvZiBzb21ldGhpbmcgbGlrZSBhIHdoZWVsIDxicj5jYW4gY3JlYXRlIGEgc2ltaWxh ciBzaXR1YXRpb24gLSB3aGVyZSB0aGUgc3RhdGljIGJhbGFuY2UgaXMgY29ycmVjdCBidXQgPGJy PnRoZSBjZW50ZXIgb2YgYmFsYW5jZSBpcyBubyBsb25nZXIgdGhlIHNhbWUgYXMgdGhlIGNlbnRl ciBvZiByb3RhdGlvbi4gIDxicj5JdCB0YWtlcyBzb3BoaXN0aWNhdGVkIGVxdWlwbWVudCBhbmQg YW4gZXF1YWxseSBzaGFycCBvcGVyYXRvciB0byBnZXQgaXQgPGJyPnJpZ2h0Ljxicj48YnI+ICAg IEJUVywgRldJVyAuLi4gRm9yIGFuIGF2ZXJhZ2UgY2FyIHRpcmUgd2l0aCAyNSIgZGlhbWV0ZXIg YXQgdGhlIDxicj50cmVhZCwgYXQgNjAgTVBILCB0aGUgd2hlZWwgaXMgdHVybmluZyB+Nzk1MCBS UE0uPGJyPjxicj48YnI+LS0gPGJyPkRhbGVfUjxicj5Db3p5IE1LSVYgIzQ5Nzxicj48YnI+PGJy Pi0tPGJyPkhvbWVwYWdlOiAgPGEgaHJlZj0iaHR0cDovL3d3dy5mbHlyb3RhcnkuY29tIj5odHRw Oi8vd3d3LmZseXJvdGFyeS5jb208L2E+Lzxicj5BcmNoaXZlIGFuZCBVblN1YjogICA8YSBocmVm PSJodHRwOi8vbWFpbC5sYW5jYWlyb25saW5lLm5ldDo4MS9saXN0cy9mbHlyb3RhcnkvTGlzdC5o dG1sIj5odHRwOi8vbWFpbC5sYW5jYWlyb25saW5lLm5ldDo4MS9saXN0cy9mbHlyb3RhcnkvTGlz dC5odG1sPC9hPjxicj48L2Jsb2NrcXVvdGU+PC9ib2R5PjwvaHRtbD4NCg== --Motorola-A-Mail-ChiIv2lCZ39zVsNq--