Pietenpol-List: RE: Rudder/fin measurements

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matronics
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Pietenpol-List: RE: Rudder/fin measurements

Post by matronics »

Original Posted By: "Oscar Zuniga"
Subject: Pietenpol-List: RE: Rudder/fin measurementsJust when I think I have found and avoided all of the errors in thedrawings, I run into another snag. Just as I was about to glue up the finaltail surface today (vertical fin) my one last measurement (my "measuretwenty times, cut only three" method) I realized that the distances for therudder and fin do not match up. It is too complicated to explain unless oneof you has seen it, but the fin will have to be 1/2" taller than the planscall for for it to fit correctly and make the bottom of the rudder line upwith the bottom of the fuselage. Anyone have any idea what I am talkingabout?Gene Rambotrying to finish SOMETHINGGene, as luck would have it, I just finished my rudder last night, so I'm very familiar with what you're saying. I clamped the verrtical fin temporarily in place, with the horizontal stabilizer shimmed level, and found the measurement for the rudder leading edge to be off 1/4 inch, with the rudder l/e clamped directly to the fin trailing edge and tailpost. However, the rudder hinges put the leading edge of the rudder farther aft, and with the downslping rudder top and upsloping bottom, another 1/4" needed to come off, so, your measurements and mine agree. The plans call for 43 1/2" for the rudder leading edge; mine came out a shade over 43". Matt Paxtonwoodflier(at)aol.com________________________________________________________________________________
matronics
Posts: 81779
Joined: Sat Mar 18, 2017 8:29 am

Re: Pietenpol-List: RE: Rudder/fin measurements

Post by matronics »

Original Posted By: "Christian Bobka"
I have received a lot of responses to my question. Most people correct thediscrepancy depending on which component was finished first. Because my finis being built last, I am just going to make the fin a little taller bymeasuring the height of the fuselage tailpost and horiz stab and buildingthe fin to the top of the rudder.Like I said, I will have to make the fin spar a little taller on top, too,to make the top contour of the rudder continue forward before sloping down(also not shown on the drawing, which suggests the top of the fin spar iseven with the top of the rudder spar . . .not so). It is interesting tolook at all of the photos on aircamper.org and notice how many fins have asmall piece added to the top of the spar for this very reason. By the way,all of my measurements and comments have taken into account the hinge gapbetween the fin and rudder.I have seen mention on here several times about making a complete list ofthe small errors in the drawings, like this example. Has anyone everattempted such a list? And, please, I am not trying to start a debate aboutthe quality of the drawings. I know that they are appropriately vague insome areas and leave room for creativity, and I think that is a good thing,but it would still be good to know where the small glitches are.________________________________________________________________________________
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