Original Posted By: "Ed Grentzer"
Greg advises me that the email address for Joe Wakely with the GN-1 for saleis wrong. You can get a holt of Joe at 507 663 9085Chris bobka________________________________________________________________________________
Pietenpol-List: Wrong email address for Joe
> RE: Pietenpol-List: Saving a penny may KILL YOU!
Original Posted By: "Oscar Zuniga"
While we're eyeball engineering, look closely at the piet wing rib and you will see some rather long, unsupported sections of capstrip in the first half of the upper cap strip,in the lift area. One of our very experienced listers mentioned not too long ago that these areas tend to sag or flatten out after many many years. I really think these areas need the support to the lower capstrip that the stitching adds. otherwise there is a whole lot of force trying to pull the capstrip out of the first gusset aft of the front spar, if that joint were to fail the whole truss assembly would be really weak or possibly fail. I would also think that screws would tend to weaken the capstrip to some extent as some of the grain would be cut by the screw, nothing critical. With all due respect, I'm sure screws have been used successfully. Just my two cents as a fellow eyeball engineer. The rib looks to me like it was designed to be supported by stitching. Ed G. Ed G.>From: "Gadd, Skip" >Reply-To: pietenpol-list(at)matronics.com>To: "'pietenpol-list(at)matronics.com'" >Subject: RE: Pietenpol-List: Saving a penny may KILL YOU!>Date: Thu, 13 Jun 2002 11:30:22 -0500>>>Mike,>Good to hear from you, I guess your last post indicates you are no longer>undercover;> I agree that one should think many times and ask a lot of people for>opinions before using non-aircraft materials.>>I also believe some aircraft things are ok on some designs and not ok on>other designs.>I think using screws to hold fabric to Piet or GN1 wings is in this>category, let me explain why.>>I consider myself an eyeball engineer, so you real engineers feel free to>jump in and correct me if I'm wrong.>>The Piet uses a truss wing rib. This design works very well when taken as a>whole, in other words you don't want to put a whole lot of stress on one>part, but rather spread the stress over the whole truss.>>When you use screws or glue to hold the fabric to the wing, you are>stressing the top cap strip alone, not a good thing. When you rib stitch >the>string goes around both top and bottom cap strips, this ties the whole >truss>together, which is a good thing.>>This is why I don't like anything but rib stitching to hold the fabric on a>Piet wing.>Skip>> >Piets and GN's have a giant cap strip that works well with screws. >Mike>MSN Photos is the easiest way to share and print your photos: http://photos.msn.com/support/worldwide ... __________
While we're eyeball engineering, look closely at the piet wing rib and you will see some rather long, unsupported sections of capstrip in the first half of the upper cap strip,in the lift area. One of our very experienced listers mentioned not too long ago that these areas tend to sag or flatten out after many many years. I really think these areas need the support to the lower capstrip that the stitching adds. otherwise there is a whole lot of force trying to pull the capstrip out of the first gusset aft of the front spar, if that joint were to fail the whole truss assembly would be really weak or possibly fail. I would also think that screws would tend to weaken the capstrip to some extent as some of the grain would be cut by the screw, nothing critical. With all due respect, I'm sure screws have been used successfully. Just my two cents as a fellow eyeball engineer. The rib looks to me like it was designed to be supported by stitching. Ed G. Ed G.>From: "Gadd, Skip" >Reply-To: pietenpol-list(at)matronics.com>To: "'pietenpol-list(at)matronics.com'" >Subject: RE: Pietenpol-List: Saving a penny may KILL YOU!>Date: Thu, 13 Jun 2002 11:30:22 -0500>>>Mike,>Good to hear from you, I guess your last post indicates you are no longer>undercover;> I agree that one should think many times and ask a lot of people for>opinions before using non-aircraft materials.>>I also believe some aircraft things are ok on some designs and not ok on>other designs.>I think using screws to hold fabric to Piet or GN1 wings is in this>category, let me explain why.>>I consider myself an eyeball engineer, so you real engineers feel free to>jump in and correct me if I'm wrong.>>The Piet uses a truss wing rib. This design works very well when taken as a>whole, in other words you don't want to put a whole lot of stress on one>part, but rather spread the stress over the whole truss.>>When you use screws or glue to hold the fabric to the wing, you are>stressing the top cap strip alone, not a good thing. When you rib stitch >the>string goes around both top and bottom cap strips, this ties the whole >truss>together, which is a good thing.>>This is why I don't like anything but rib stitching to hold the fabric on a>Piet wing.>Skip>> >Piets and GN's have a giant cap strip that works well with screws. >Mike>MSN Photos is the easiest way to share and print your photos: http://photos.msn.com/support/worldwide ... __________