Brodhead Pietenpol Association

Original Posted By: Jimmy Courtney
Subject: Pietenpol-List: Progress (Caution long download)Dear Piet GangWell...sometimes progress means taking a step backwards. It seems like lately every time I get a chance to work on the piet I end up re-doing somethingthat the original builder has done. Re work has included landing gear changes,rudder control cable changes, firewall changes, tail brace wire changes... andnow... this.I just spent time this weekend removing unnecessary floorboards. Chuck... I am sure you are happy to know that we decided to make this change. The original bulder of the 40-yr-old Piet added 1/4 in plywood floorboard to the airplane. When Chuck was here in July, he recommended that we remove it to saveweight and to allow for better access for inspection of the landing gear boltsand engine mount bolts and of the glue joints in the fuselage structure. Lon and I were hesitant because we had already done some work toward finishing the inside and we weren't excited about having to un-do some of our work and some ofthe original builder's work. But this has been on my mind lately and bugging me to the point that I bit the bullet this weekend and started taking out floor. This included using a wood chisel to remove spacer/support blocks usedunder the " false floor. It all went better than I would have guessed. As a result, I think I have managed to trim about 7 pounds from the empty weight. See attached picture.Chuck...as you'll recall,... we were also concerned about whether the old original glue joints were sound. I am happy (while also a bit dissgruntled) toreport that the joints are sound. I know this because when removing the floorsupport blocks... the joints were so good that I ended up tearing away some ofthe material from the bottom plywood. This will detract from the cosmetic appearance. Still, we will make sure that the final product is structurally sound. But all in-all... I am happy with these changes. With the floor removed,I am now installing little sheet metal "wear plates" under each rudder pedal. See the mocked up patterns in the picture.Anyway....It feels like I didn't make much progress in several hours of work. Sometimes you have to go backward to move forward.Terry________________________________________________________________________________Date: Mon, 6 Sep 2004 23:18:15 -0700 (PDT)

Original Posted By: "Larry Ragan"
Subject: Re: Pietenpol-List: weldingKit Fox and Avid used MIG welders on their respective 4130 fuselages. My Avid was wrecked by a commercial pilot in 1993 (stalled out at appx. 200 feet after takeoff) and the airplane was demolished. The pilot was not injured,but chromoly tubing (4130) was broken in a number of places. However, not a single MIG weld joint came apart. I also had welded a toe extension on the fuselage using a TIG system. Not a single TIG joint broke either, yet the crash was so traumatic to the fuselage and wings, tubing failed and broke in places other than joints.I'd say to double check the Tony Bineglis series of books and get info from this source. Most of the "old-school" thought still suggests using gas weldinghowever, but I'd say research this as best as you can, and if you aren't an experienced welder, get some schooling or take it to a pro.As a sidebar to this story, the Avid wing has aluminum tubular spars and wooden ribs. The wooden ribs are glued the spar (don't be alarmed) and the processthat Dean Wilson developed (Dean designed the Avid and the Kitfox and the Global Explorer to name a few) has never failed. When my Avid was wrecked, nota single wood to aluminum joint failed either. Furthermore, the fabric is glued (not rib-stitched) to the rib. There was very little evidence of fabric separation from the rib, except in the area where the wing actually impacted theasphalt runway. The capstrip on the Avid, however, is 3 times as wide as an AirCamper.I'm not suggesting that rib-stitching not be used on an Air Camper. My Avid was an Aerobatic Speedwing and the Avid factory demonstrator was an Aerobatic tri-gear. We did all sorts of unusual maneuvers in these birds and fabric has never, ever pulled away from a wooden capstrip. But, the capstrip was very wide, and the glue process was much improved over what Bernard had access to manyyears ago.Sterling BrooksCentral Texas________________________________________________________________________________