Original Posted By: Chris Tracy
I did a search for this and no help.What size stiffeners do I need for the long fuselage and where do I position them?I'm not putting a gas tank in front. Using Corvair engine.Should I place the forward edge of the front stiffener against the 15" mark"? Justmake my stiffeners to whatever size needed and position them based from that15" point?Do the cowl supports and instrument panels attach to the cross struts?Trying to figure it out from the short fuselage plans is not helping.Thank you,John Cronin--------JohnRead this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Wed, 1 Feb 2017 02:54:02 +0000 (UTC)
Pietenpol-List: Stiffeners and cross struts
Pietenpol-List: Re: Stiffeners and cross struts
Original Posted By: "taildrags"
OK, so I found the Wynne articles and have read through them. First comment: ifyou don't have them and you want to learn, send $25 to Doc's Piet Shop, P.O.Box 1001, Neenah WI 54957 in check, money order, or cash and you'll get a setof the articles and commentary from Doc.Now for the bottom line: "it depends" ;o) You ask where the axle should be placedrelative to the firewall, but all of the available information referencesthe axle location with respect to the datum, which is the wing leading edge inthe articles and commentary and is a common datum for aircraft W&B. The twistto this is that the wing on a Piet can be moved forward and aft by tilting thewing cabanes, so in effect the datum is a moving target. This can be a goodthing if the airplane is tail heavy, but it doesn't sound like yours is goingto be, with an extended front bay and a Ford engine.The articles conclude that the best axle placement for a modern Air Camper withbrakes is about 3" aft of the leading edge of the wing with the aircraft level(top longerons level, as they would be when you're conducting your W&B). Readthe articles to learn how that number was arrived at, but suffice it to saythat there is a good reason. I will admit that the axle distance on my airplaneis farther aft than optimum but I don't remember by how much. When you'rebuilding your airplane, you don't know anything about where the wing leadingedge is going to end up, so you've got to check things as the build progresses.If you build to the plans you've got (with cabanes vertical), the leading edgeof the wing will be 16-1/4" aft of the firewall with that long 23" bay atthe front of your fuselage, so the axle should be placed 19-1/4" aft of the firewall.I got that dimension by looking at Drawing No. 1 of the 1933 Hoopmanplans (upper right corner), the front cabane mounting point is 14-1/4" from thefirewall and the wing leading edge is 7-1/2" from the firewall. If you lengthenthe front bay by 8-3/4", that moves the wing leading edge to 16-1/4" fromthe firewall and the axle 3" aft of that.In the Wynne study there is one aircraft with a fuselage length like yours, 172.375".Like the other five aircraft in that initial sampling, it has the axlefarther aft than optimum, 7.125" aft of the wing leading edge.--------Oscar ZunigaMedford, ORAir Camper NX41CC "Scout"A75 power, 72x36 Culver propRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Stiffeners and cross struts
OK, so I found the Wynne articles and have read through them. First comment: ifyou don't have them and you want to learn, send $25 to Doc's Piet Shop, P.O.Box 1001, Neenah WI 54957 in check, money order, or cash and you'll get a setof the articles and commentary from Doc.Now for the bottom line: "it depends" ;o) You ask where the axle should be placedrelative to the firewall, but all of the available information referencesthe axle location with respect to the datum, which is the wing leading edge inthe articles and commentary and is a common datum for aircraft W&B. The twistto this is that the wing on a Piet can be moved forward and aft by tilting thewing cabanes, so in effect the datum is a moving target. This can be a goodthing if the airplane is tail heavy, but it doesn't sound like yours is goingto be, with an extended front bay and a Ford engine.The articles conclude that the best axle placement for a modern Air Camper withbrakes is about 3" aft of the leading edge of the wing with the aircraft level(top longerons level, as they would be when you're conducting your W&B). Readthe articles to learn how that number was arrived at, but suffice it to saythat there is a good reason. I will admit that the axle distance on my airplaneis farther aft than optimum but I don't remember by how much. When you'rebuilding your airplane, you don't know anything about where the wing leadingedge is going to end up, so you've got to check things as the build progresses.If you build to the plans you've got (with cabanes vertical), the leading edgeof the wing will be 16-1/4" aft of the firewall with that long 23" bay atthe front of your fuselage, so the axle should be placed 19-1/4" aft of the firewall.I got that dimension by looking at Drawing No. 1 of the 1933 Hoopmanplans (upper right corner), the front cabane mounting point is 14-1/4" from thefirewall and the wing leading edge is 7-1/2" from the firewall. If you lengthenthe front bay by 8-3/4", that moves the wing leading edge to 16-1/4" fromthe firewall and the axle 3" aft of that.In the Wynne study there is one aircraft with a fuselage length like yours, 172.375".Like the other five aircraft in that initial sampling, it has the axlefarther aft than optimum, 7.125" aft of the wing leading edge.--------Oscar ZunigaMedford, ORAir Camper NX41CC "Scout"A75 power, 72x36 Culver propRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Stiffeners and cross struts
Pietenpol-List: Re: Stiffeners and cross struts
Original Posted By: "Catdesigns"
John: Westcoastpiet to the rescue (again)!! There are dozens and dozens of excellent"bare fuselage" shots on this site, but let's give Chris Tracy the spotlight.Take a look at his airplane and see if this doesn't help clarify thingsa bit:http://www.westcoastpiet.com/images/Chr ... 67.JPGNote that if you're not using the Ford engine, you don't need the forward "tray".If you're not using a nose tank, you don't really need the crossmember thatcarries the tank straps, either. What you do need are some stiffeners, andyou'll see one behind the front instrument panel and another one between the rearinstrument panel and the top of the front seat back. My airplane is framedjust like this, except that mine has an extra crossmember to carry the nosetank straps.Gary Boothe's is another good one to look at:http://www.westcoastpiet.com/images/Gar ... _1.jpgRick Schreiber's:http://www.westcoastpiet.com/images/Ric ... -----Oscar ZunigaMedford, ORAir Camper NX41CC "Scout"A75 power, 72x36 Culver propRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Stiffeners and cross struts
John: Westcoastpiet to the rescue (again)!! There are dozens and dozens of excellent"bare fuselage" shots on this site, but let's give Chris Tracy the spotlight.Take a look at his airplane and see if this doesn't help clarify thingsa bit:http://www.westcoastpiet.com/images/Chr ... 67.JPGNote that if you're not using the Ford engine, you don't need the forward "tray".If you're not using a nose tank, you don't really need the crossmember thatcarries the tank straps, either. What you do need are some stiffeners, andyou'll see one behind the front instrument panel and another one between the rearinstrument panel and the top of the front seat back. My airplane is framedjust like this, except that mine has an extra crossmember to carry the nosetank straps.Gary Boothe's is another good one to look at:http://www.westcoastpiet.com/images/Gar ... _1.jpgRick Schreiber's:http://www.westcoastpiet.com/images/Ric ... -----Oscar ZunigaMedford, ORAir Camper NX41CC "Scout"A75 power, 72x36 Culver propRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Stiffeners and cross struts
Original Posted By: "Clif Dawson"
JohnOn the long fuselage place the cross braces in the sam location relative to theside clusters. They are also the same size as shown on the short fuselage plans.Yes, the instrument panel and cowl support are attached tothe ccross support.--------ChrisSacramento, CAWestCoastPiet.comRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
JohnOn the long fuselage place the cross braces in the sam location relative to theside clusters. They are also the same size as shown on the short fuselage plans.Yes, the instrument panel and cowl support are attached tothe ccross support.--------ChrisSacramento, CAWestCoastPiet.comRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
Re: Pietenpol-List: Re: West Coast Piet
Original Posted By: (null) raykrause
That makes at least two of us. I would not put ANY of myinformation on there!Clif ----- Original Message -----
That makes at least two of us. I would not put ANY of myinformation on there!Clif ----- Original Message -----
Re: Pietenpol-List: Re: West Coast Piet
Original Posted By: (null) raykrause
That makes at least two of us. I would not put ANY of myinformation on there!Clif ----- Original Message -----
That makes at least two of us. I would not put ANY of myinformation on there!Clif ----- Original Message -----
Re: Pietenpol-List: Re: West Coast Piet
Original Posted By: Chris Tracy
Hi Chris,Glad I ducked!...... anyway, thanks for getting back to me at least. I also agree that it is a bit of a waste that you can't archive or search things on facebook. Apart from the generally helpful people on this list, being able to check the archives is, and always has been one of the things I liked about the Matronics list. I must admit that at first I was against the Facebook site, but now I think that using both sites is a good idea, so that's what I will do for the time being.As I said in my last post, you have a great site yourself, keep up the good work.CheersMark
Hi Chris,Glad I ducked!...... anyway, thanks for getting back to me at least. I also agree that it is a bit of a waste that you can't archive or search things on facebook. Apart from the generally helpful people on this list, being able to check the archives is, and always has been one of the things I liked about the Matronics list. I must admit that at first I was against the Facebook site, but now I think that using both sites is a good idea, so that's what I will do for the time being.As I said in my last post, you have a great site yourself, keep up the good work.CheersMark
Pietenpol-List: Re: Stiffeners and cross struts
Original Posted By: "CatDesigns"
Thanks for the help. I look at builder photos whenever possible, but I can't determinespecific measurements from them, and I want to make sure before I startconstructing everything top based on the 15" point.John--------JohnRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
Thanks for the help. I look at builder photos whenever possible, but I can't determinespecific measurements from them, and I want to make sure before I startconstructing everything top based on the 15" point.John--------JohnRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
RE: Pietenpol-List: Re: West Coast Piet
Original Posted By: owner-pietenpol-list-server(at)matronics.com
MarkIt did sound a bit harsh. Sorry about that.
MarkIt did sound a bit harsh. Sorry about that.
Re: Pietenpol-List: Re: West Coast Piet
Original Posted By: CatDesigns
Chris,Thanks for that comment, I appreciate it. I will have to put the odd picture and updates on this list again. My project is still alive, but life gets in the way allot so progress is sloooooow.Anyway, I hope we can ALL continue to help each other out when we need it.CheersMark StanleyJapan
Chris,Thanks for that comment, I appreciate it. I will have to put the odd picture and updates on this list again. My project is still alive, but life gets in the way allot so progress is sloooooow.Anyway, I hope we can ALL continue to help each other out when we need it.CheersMark StanleyJapan