Return-Path: Sender: (Marvin Kaye) To: lml Date: Tue, 08 Apr 2003 11:38:20 -0400 Message-ID: X-Original-Return-Path: Received: from imo-d05.mx.aol.com ([205.188.157.37] verified) by logan.com (CommuniGate Pro SMTP 4.1b2) with ESMTP id 2110072 for lml@lancaironline.net; Tue, 08 Apr 2003 11:30:47 -0400 Received: from Sky2high@aol.com by imo-d05.mx.aol.com (mail_out_v34.21.) id q.ae.3d6e3b2c (4320) for ; Tue, 8 Apr 2003 11:30:37 -0400 (EDT) From: Sky2high@aol.com X-Original-Message-ID: X-Original-Date: Tue, 8 Apr 2003 11:30:37 EDT Subject: Re: [LML] 360 flap Question X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="part1_ae.3d6e3b2c.2bc4451d_boundary" X-Mailer: Unknown sub 90 --part1_ae.3d6e3b2c.2bc4451d_boundary Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 4/8/2003 9:06:06 AM Central Daylight Time, panelmaker@earthlink.net writes: > The spar on the bottom flap skin is shown to be in front of the foam insert > on the blueprints (J). But that's not possible on my bottom skin. > > Is it alright to put that spar on top of the foam insert? This will shorten > the phenolic insert (bellhorn) some. > Jim, The flaps can undergo very strong twisting moments because of their length and the location of the positioning pushrod. From a structural viewpoint, I believe it is best to carve out the foam, use flox and the recommended bid layers plus bid to replace that which was cut out to remove the foam (I think this is two layers of glass). I did this procedure on mine, although it may be stronger to first cut the glass and reshape the foam, close out that area (probably 2-BID) and then proceed with the spar work per the directions. <<<>>>> No. Use the bottom. Because of molding differences, first determine if the bottom trailing tip of the filets are laterally level (when the fuselage is level - both laterally and longitudinally). If not, consider re-working the filets. Assuming your plane is now level and the wingtip jigs are correctly positioning the tips, place a straight-edge device from the trailing edge bottom of the filet to the trailing edge bottom of the wingtip. The device can be a combination of straight edge for support while building and a laser beam. The filet tip is important (one was .5 inch lower on mine) because it can introduce a slight twist in the cruise wing flap position leading to a wing heavy condition. Note that where your ailerons fly in cruise may not be the same as their neutral non-flight position. The flaps may also require rigging changes after some flight tests. <<<<>>> No. The wing tip rib determines the position. Do not use cosmetics for matching control surfaces. I don't have my material handy, but I think the ailerons are in a slight reflex position - check the wingtip rib. Also, the flap upper and lower skins are curved while the ailerons skins are straight and the aileron training edge is 1/4 inch thick while the flap trailing edge is thin. When the aileron was built/installed, the same procedure as the flap should be used - i.e. underside wingtip trailing edge --> straight edge --> underside filet trailing edge assuming the wingtip and filet have been checked for position. Minor mismatches in the fit and finish area (top, visible while sitting on the ground) can be fixed with micro fill at a later time. <<<>>> No again. There are no category of questions that should not be asked. I only hope that my comments help you re-think your approach. If I have been obscure, please call me at home in the evening (630-655-4811) or cell at 630-561-0400. Scott Krueger Sky2high@aol.com LNC2 N92EX IO320 Aurora, IL (KARR) --part1_ae.3d6e3b2c.2bc4451d_boundary Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable In a message dated 4/8/2003 9:06:06 AM Central Dayligh= t Time, panelmaker@earthlink.net writes:

The spar on the bottom flap ski= n is shown to be in front of the foam insert
on the blueprints (J). But that's not possible on my bottom skin.

Is it alright to put that spar on top of the foam insert? This will shorten<= BR> the phenolic insert (bellhorn) some.

Jim,

The flaps can undergo very strong twisting moments because of their length a= nd the location of the positioning pushrod. From a structural viewpoin= t, I believe it is best to carve out the foam, use flox and the recommended=20= bid layers plus bid to replace that which was cut out to remove the foam (I=20= think this is two layers of glass). I did this procedure on mine, although i= t may be stronger to first cut the glass and reshape the foam, close out tha= t area (probably 2-BID) and then proceed with the spar work per the directio= ns.

<<<<If the promximal end of the flap meets the fillet of the fus= elage (top to
top), does the distal top skin of the flap tie with the top of the aileron skin in this condition?>>>>>

No. Use the bottom. Because of molding differences, first determ= ine if the bottom trailing tip of the filets are laterally level (when the f= uselage is level - both laterally and longitudinally). If not, conside= r re-working the filets. Assuming your plane is now level and the wing= tip jigs are correctly positioning the tips, place a straight-edge device fr= om the trailing edge bottom of the filet to the trailing edge bottom of the=20= wingtip. The device can be a combination of straight edge for support=20= while building and a laser beam. The filet tip is important (one was .= 5 inch lower on mine) because it can introduce a slight twist in the cruise=20= wing flap position leading to a wing heavy condition. Note that where=20= your ailerons fly in cruise may not be the same as their neutral non-flight=20= position. The flaps may also require rigging changes after some flight= tests.

<<<<<Does in-trail for the aileron mean you place a straight=20= edge tangent to the
top skin TE of the wing and the top skin of the aileron is tangent to the straight edge too?>>>>

No. The wing tip rib determines the position. Do not use cosmetics for match= ing control surfaces. I don't have my material handy, but I think the=20= ailerons are in a slight reflex position - check the wingtip rib. Also= , the flap upper and lower skins are curved while the ailerons skins are str= aight and the aileron training edge is 1/4 inch thick while the flap trailin= g edge is thin. When the aileron was built/installed, the same procedu= re as the flap should be used - i.e. underside wingtip trailing edge -->=20= straight edge --> underside filet trailing edge assuming the wingtip and=20= filet have been checked for position.

Minor mismatches in the fit and finish area (top, visible while sitting on t= he ground) can be fixed with micro fill at a later time.

<<<<These are fairly simplistic questions>>>>

No again. There are no category of questions that should not be asked.= I only hope that my comments help you re-think your approach. I= f I have been obscure, please call me at home in the evening (630-655-4811)=20= or cell at 630-561-0400.

Scott Krueger
Sky2high@aol.com
LNC2 N92EX IO320 Aurora, IL (KARR) --part1_ae.3d6e3b2c.2bc4451d_boundary--