Original Posted By:> owner-pietenpol-list-server(at)matronics.com
Subject: RE: Pietenpol-List: verifying tach/cable sizes/cowling fab> > Hi Douwe,> > Answers to your questions:> > 1. Strobe tachs are available, but not cheap. What I do is find a friend> who owns one and use his.> > 2. Why run the cables all the way to the tailpost? Cable is heavy and> expensive, and if the cable is needed (i.e., in a crash) you are subjecting> the structure to a load in a direction it is not really designed to resist.> I would carry the cables just far enough aft to give you a proper angle on> the cables and attach them to the upper longerons at a point where the> longerons have plenty of reinforcement (where the uprights and diagonals> come in). I believe a 20 G limit is what is usually considered adequate.> So if you weigh 200 lbs, and your entire weight is to be suspended from> these cables, they will have to be capable of withstanding 4,000 lbs of load> (2,000 lbs apiece), which will require at least 1/8" diameter cable. By the> time you add all the fittings you will have a couple of pounds of weight> back where you really don't want extra weight.> If you just attach the cables to the top longerons, drill the bolt holes> through the longerons midway between the top and bottom surfaces of the> longeron, with the hole running horizontally. Make sure there are gussets> on either side of the longeron at that point for extra reinforcement.> > 3. I used 2024-T3 aluminum .025" thick for my cowlings. Large openings> like the cockpit cutouts and cutouts around the engine are best done on a> wood-cutting bandsaw with a metal cutting blade. Holes are best done with a> holesaw. All can be cut with tin snips, if you really like blisters and> lacerations. Cut to the outside of your finished line and finish it up with> a vixen file (for the straight portions) or a drum sander (for curves).> > Hope this helps,> > Jack Phillips> NX899JP> > -----Original Message-----
Pietenpol-List: verifying tach/cable sizes/cowling fab
Pietenpol-List: Re: verifying tach/cable sizes/cowling fab
Original Posted By: "Catdesigns"
link.net>Hey gang,Three questions:1.- Any suggestions for inexpensively verifying my tach?- is there some sortof cheap strobe type counter I can use on the prop?2.- I am running my shoulder belt attachment back to my tailpost and wantedthoughts on what size cable to use.- What g's are we realisticallyprotecting against after which it's just silliness?3.- What gauge aluminum should I use for my cowling?- what is the best meansof cutting out openings and holes?Thanks, as always!!Douwespraying fuse next week, then it's all painted!!le, List Admin.________________________________________________________________________________Subject: Pietenpol-List: Re: verifying tach/cable sizes/cowling fab
link.net>Hey gang,Three questions:1.- Any suggestions for inexpensively verifying my tach?- is there some sortof cheap strobe type counter I can use on the prop?2.- I am running my shoulder belt attachment back to my tailpost and wantedthoughts on what size cable to use.- What g's are we realisticallyprotecting against after which it's just silliness?3.- What gauge aluminum should I use for my cowling?- what is the best meansof cutting out openings and holes?Thanks, as always!!Douwespraying fuse next week, then it's all painted!!le, List Admin.________________________________________________________________________________Subject: Pietenpol-List: Re: verifying tach/cable sizes/cowling fab
Pietenpol-List: verifying tach/cable sizes/cowling fab
Original Posted By: "Jack Phillips"
Hey gang,Three questions:1. Any suggestions for inexpensively verifying my tach? is there some sortof cheap strobe type counter I can use on the prop?2. I am running my shoulder belt attachment back to my tailpost and wantedthoughts on what size cable to use. What g's are we realisticallyprotecting against after which it's just silliness?3. What gauge aluminum should I use for my cowling? what is the best meansof cutting out openings and holes?Thanks, as always!!Douwespraying fuse next week, then it's all painted!!________________________________________________________________________________
Hey gang,Three questions:1. Any suggestions for inexpensively verifying my tach? is there some sortof cheap strobe type counter I can use on the prop?2. I am running my shoulder belt attachment back to my tailpost and wantedthoughts on what size cable to use. What g's are we realisticallyprotecting against after which it's just silliness?3. What gauge aluminum should I use for my cowling? what is the best meansof cutting out openings and holes?Thanks, as always!!Douwespraying fuse next week, then it's all painted!!________________________________________________________________________________
RE: Pietenpol-List: verifying tach/cable sizes/cowling fab
Original Posted By: owner-pietenpol-list-server(at)matronics.com
Hi Douwe,Answers to your questions:1. Strobe tachs are available, but not cheap. What I do is find a friendwho owns one and use his.2. Why run the cables all the way to the tailpost? Cable is heavy andexpensive, and if the cable is needed (i.e., in a crash) you are subjectingthe structure to a load in a direction it is not really designed to resist.I would carry the cables just far enough aft to give you a proper angle onthe cables and attach them to the upper longerons at a point where thelongerons have plenty of reinforcement (where the uprights and diagonalscome in). I believe a 20 G limit is what is usually considered adequate.So if you weigh 200 lbs, and your entire weight is to be suspended fromthese cables, they will have to be capable of withstanding 4,000 lbs of load(2,000 lbs apiece), which will require at least 1/8" diameter cable. By thetime you add all the fittings you will have a couple of pounds of weightback where you really don't want extra weight.If you just attach the cables to the top longerons, drill the bolt holesthrough the longerons midway between the top and bottom surfaces of thelongeron, with the hole running horizontally. Make sure there are gussetson either side of the longeron at that point for extra reinforcement.3. I used 2024-T3 aluminum .025" thick for my cowlings. Large openingslike the cockpit cutouts and cutouts around the engine are best done on awood-cutting bandsaw with a metal cutting blade. Holes are best done with aholesaw. All can be cut with tin snips, if you really like blisters andlacerations. Cut to the outside of your finished line and finish it up witha vixen file (for the straight portions) or a drum sander (for curves).Hope this helps,Jack PhillipsNX899JP-----Original Message-----
Hi Douwe,Answers to your questions:1. Strobe tachs are available, but not cheap. What I do is find a friendwho owns one and use his.2. Why run the cables all the way to the tailpost? Cable is heavy andexpensive, and if the cable is needed (i.e., in a crash) you are subjectingthe structure to a load in a direction it is not really designed to resist.I would carry the cables just far enough aft to give you a proper angle onthe cables and attach them to the upper longerons at a point where thelongerons have plenty of reinforcement (where the uprights and diagonalscome in). I believe a 20 G limit is what is usually considered adequate.So if you weigh 200 lbs, and your entire weight is to be suspended fromthese cables, they will have to be capable of withstanding 4,000 lbs of load(2,000 lbs apiece), which will require at least 1/8" diameter cable. By thetime you add all the fittings you will have a couple of pounds of weightback where you really don't want extra weight.If you just attach the cables to the top longerons, drill the bolt holesthrough the longerons midway between the top and bottom surfaces of thelongeron, with the hole running horizontally. Make sure there are gussetson either side of the longeron at that point for extra reinforcement.3. I used 2024-T3 aluminum .025" thick for my cowlings. Large openingslike the cockpit cutouts and cutouts around the engine are best done on awood-cutting bandsaw with a metal cutting blade. Holes are best done with aholesaw. All can be cut with tin snips, if you really like blisters andlacerations. Cut to the outside of your finished line and finish it up witha vixen file (for the straight portions) or a drum sander (for curves).Hope this helps,Jack PhillipsNX899JP-----Original Message-----
Re: RE: Pietenpol-List: verifying tach/cable sizes/cowling fab
Original Posted By: Jack Phillips
Subject: Re: RE: Pietenpol-List: verifying tach/cable sizes/cowling fabI have a small device that works something like a tuning fork. Pretty cheap. Wecompared it to a strobe and it was very close. You stand 25 feet in front ofthe plane, slide a plastic holder down to the indicated RPM and look througha peephole and flip a small stiff rod with your finger. The rod viberates. Ifthe prop moves one way it is too fast, If it moves the other it is too slow. Havethe pilot adjust the throttle until the prop is stationary, then compare theRPM to the setting on the device. sounds more complicated than it is. Blue Skies,Steve ----- Original Message -----
Subject: Re: RE: Pietenpol-List: verifying tach/cable sizes/cowling fabI have a small device that works something like a tuning fork. Pretty cheap. Wecompared it to a strobe and it was very close. You stand 25 feet in front ofthe plane, slide a plastic holder down to the indicated RPM and look througha peephole and flip a small stiff rod with your finger. The rod viberates. Ifthe prop moves one way it is too fast, If it moves the other it is too slow. Havethe pilot adjust the throttle until the prop is stationary, then compare theRPM to the setting on the device. sounds more complicated than it is. Blue Skies,Steve ----- Original Message -----
> Pietenpol-List: verifying tach/cable sizes/cowling fab
Original Posted By: H RULE
Original Posted By: "Gardiner Mason"
DouweI used 1/8th inch cable anchored in 3 places. You can see my basic setup herehttp://www.westcoastpiet.com/build_pictures_2.htmFor you steely eyed people who I know will comment, I did use shorter bolts toattach the seat belts and did away with the large wood washers.Chris--------Chris TracySacramento, CAWestCoastPiet.comRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
DouweI used 1/8th inch cable anchored in 3 places. You can see my basic setup herehttp://www.westcoastpiet.com/build_pictures_2.htmFor you steely eyed people who I know will comment, I did use shorter bolts toattach the seat belts and did away with the large wood washers.Chris--------Chris TracySacramento, CAWestCoastPiet.comRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
Pietenpol-List: Re: verifying tach/cable sizes/cowling fab
Original Posted By: "Catdesigns"
The R/C guys (myself included) use an optical tach. The I have is from GloBee. I know a buddy of mine used one to test the tach in his Skybolt.I'd give a link but this phone won't let me copy and paste (yet).They have them at towerhobbies.com for $28.Wayne Bressler Jr.Taildraggers, Inc.taildraggersinc.comSent from my iPhone________________________________________________________________________________Subject: Pietenpol-List: Re: verifying tach/cable sizes/cowling fab
The R/C guys (myself included) use an optical tach. The I have is from GloBee. I know a buddy of mine used one to test the tach in his Skybolt.I'd give a link but this phone won't let me copy and paste (yet).They have them at towerhobbies.com for $28.Wayne Bressler Jr.Taildraggers, Inc.taildraggersinc.comSent from my iPhone________________________________________________________________________________Subject: Pietenpol-List: Re: verifying tach/cable sizes/cowling fab
Original Posted By: "Douwe Blumberg"
I should add that the reason I used three anchor points was to make the load aneach anchor as low as possible. I know from rock climbing that the angle betweenthe two anchor points is very important when it comes to lowering the loadon the anchors. What you want to shoot for is about a 20 degree angle betweeneach arm of the the sling attached to the two anchor points. This will loadeach anchor with 1/2 the actual load. Any angle greater then this and you willload the anchors more then half. For a good discussion on this topic see this web pagehttp://www.southeastclimbing.com/faq/faq_ancho ... -----Chris TracySacramento, CAWestCoastPiet.comRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
I should add that the reason I used three anchor points was to make the load aneach anchor as low as possible. I know from rock climbing that the angle betweenthe two anchor points is very important when it comes to lowering the loadon the anchors. What you want to shoot for is about a 20 degree angle betweeneach arm of the the sling attached to the two anchor points. This will loadeach anchor with 1/2 the actual load. Any angle greater then this and you willload the anchors more then half. For a good discussion on this topic see this web pagehttp://www.southeastclimbing.com/faq/faq_ancho ... -----Chris TracySacramento, CAWestCoastPiet.comRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________