Announcement

Collapse
No announcement yet.

flat sheet cowl?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • flat sheet cowl?

    I talked to a guy a few weeks back who swears his lower cowl is made from a flat sheet, no compound curves. Yet a forum search yields only discussion of english wheel formed compound curve cowls.
    Are there two types of cowls? Compound curve and flat sheet? How do I tell which type I have?
    Bob Gustafson
    NC43913
    TF#565

  • #2
    Re: flat sheet cowl?

    I think the flat sheet cowls were not used until the F21. I know it was only the later birds that had them. IF you put a straight edge on the surface where the "cheeks" would be and it rocks from end to end, you do NOT have a flat sheet cowl. Once you see one, you will know.
    Richard Pearson
    N43381
    Fort Worth, Texas

    Comment


    • #3
      Re: flat sheet cowl?

      There is something about the look of the F21/22 lower cowls that make me believe that they don't have the same nice compound shapes as the other models.

      In 2004, at the Taylorcraft Factory Fly-in in LaGrange TX, Harry Ingram demonstrated the process they were using for FORM the compound shape of the lower cowls (I believe this was for his planned Light Sport model based on the F19). I am not sure how well this process worked because he only demonstrated part of the process. Here is how I remember it though.
      • He had a male wooden mould for the correct shape.
      • He took a dead-soft piece of aluminum (I assume it was 5052-O)
      • He then laid the flat sheet over the mould and began the forming process
      • He started with a gentle flexure of the sheet cowl to a point where he could clamp it on two sides.

      Next
      • He took a piece of rubber approx 3/4 inch thick in the shape of a paddle.
      • He used the paddle to "slap" against the sheet, slowly forming over the mould.
      • Periodically, he would stop and re-position or add clamps, working them down over the mould.


      Harry claimed (now there's a good one to think on) that this method worked well for making the bottom cowl. But then... how many did he really produce? Maybe this was some of the same ol' "stuff" from him.
      Terry Bowden, formerly TF # 351
      CERTIFIED AERONAUTICAL PRODUCTS, LLC
      Consultant D.E.R. Powerplant inst'l & Engines
      Vintage D.E.R. Structures, Electrical, & Mechanical Systems
      BC12D, s/n 7898, N95598
      weblog: Barnstmr's Random Aeronautics
      [email protected]

      Comment


      • #4
        Re: flat sheet cowl?

        I bought a lower cowl from Dorthy Ferris at the Taylorcraft factory (back when it was the GOOD Taylorcraft). It wouldn't even connect up to my 45 and was definitely one of the "Flat" cowls. When you laid it on the hangar floor it would lay completely flat on they floor. My original 45 cowl (and the one on my 41 now) would stand up on the back edge and both have a distinct 3D curve to them.

        I sold the one from the factory to another Taylorcraft owner with a later model and it hooked right up.

        I know for sure, the pre-war lower cowls were formed. There is a picture in Chets book showing a hydropress at the old factory making instrument panels. From its size, it was NOT bought just to make ribs and instrument panels. You can make a cowl by Hydropressing it on a Kirksite die (the best way for mass production), hand forming with an English Wheel or slap forming it on a Buck. I have no doubt Harry would demonstrate the slapping process to a group of people. I also have no doubt he never finished a single cowl that way. It is a LOT of work and takes some skill and patience (neither are things Harry had a lot of). He probably was just trying to get people to place orders and give deposits.

        A REALLY good body shop can make you a cowl free hand with a wheel, but they will need a frame buck or the plane there to repeatedly fit the cowl up to. It is true magic to watch a flat piece of aluminum slowly curve around into a smooth curved cowl, but it will cost you an arm and a leg.

        I have done slap forming and hand bumping with a mallet and shot bag. Anyone can learn it. All you need is time and patience. I have had an English wheel on my Christmas list for at least two decades. All of my fingers are still round and I don't have a wheel yet.

        Hank

        An English wheel can crush a thumb or finger flat faster than a sneeze!

        Comment


        • #5
          Re: flat sheet cowl?

          I had a conversation with Dorothy about the material used in making instrument panels. She said the they used 3003-S and it stiffened when stamped. I bet she used the same for the cowling. Dick
          TF #10

          Comment


          • #6
            Re: flat sheet cowl?

            About two years ago a Metal Workers mag did a 4 or 5 piece article on a beautiful English Wheel you could make in your shop. I was set to do so until it got way too involved, but it was massive with a 6" steel pipe spine and arms. You had to buy only the wheels them selves to finish. It weighed about 800lbs. when finished, looked beautiful and I still wished I had built it. I have all the articles but not the time nor the inclination!
            Larry
            "I'm from the FAA and we're not happy, until your not happy."

            Comment


            • #7
              Re: flat sheet cowl?

              Back on 5-18-2009 Mark Julicher started a thread on NOS Cowling. He posted many photos of the fitting process.

              But, if you look at the pictures, the bottom cowls seems to be a flat sheet. It does not seem to have the compound curve when viewed from the side.

              The cowling is a short mount with suit case latches. Maybe Mark could tell us for sure.
              Ray

              Comment


              • #8
                Re: flat sheet cowl?

                I bought my cowling from Harry, I did all of the finish work and fitting and it fits like a dream. It was .050 material and soft. Probably 3003, due to its price. I guess I was lucky. Tim
                N29787
                '41 BC12-65

                Comment


                • #9
                  Re: flat sheet cowl?

                  Does anyone have any photos of the flat sheet cowl that they could post? I am building an experimental clip-wing and would like to fabricate a new lower cowl but don't have the talent or tools to make a compound one.
                  Thanks,
                  Hal

                  Comment


                  • #10
                    Re: flat sheet cowl?

                    Hey there tribe,
                    I live in the heart of stock car racing and english wheels abound here, if there is enough of a interest in this I'd be willing to bet that I could find someone thats wants to make a extra buck making these by hand, I have both the BL and BC lower cowls (pre war) that could be used as a starting point. I live 6 miles from Earhart's shop and within 15 miles of probably 15 other NASCAR race shops and numerous other shops

                    Comment


                    • #11
                      Re: flat sheet cowl?

                      Hi Bird,

                      Is that BC pre-war cowl open or closed?? h
                      20442
                      1939 BL/C

                      Comment


                      • #12
                        Re: flat sheet cowl?

                        Michael (Bird),
                        If what you have is an open cowl, I have the cowl off my 45 (closed) here in Virginia Beach (not that far). It's a little banged up since I haven't started repairing it yet, but it would be good for a guide and the boot is off the plane too for fit up and alignment.
                        Hank

                        Comment


                        • #13
                          Re: flat sheet cowl?

                          This would be great. I can supply my dinged and patched lower cowl. It is from a 1946 BC-12D. I can get any alloy of aluminum from Stock Car Steel in Mooresville. All we need is someone with the talent to form them.
                          Hal
                          Cornelius, NC

                          Originally posted by Bird View Post
                          Hey there tribe,
                          I live in the heart of stock car racing and english wheels abound here, if there is enough of a interest in this I'd be willing to bet that I could find someone thats wants to make a extra buck making these by hand, I have both the BL and BC lower cowls (pre war) that could be used as a starting point. I live 6 miles from Earhart's shop and within 15 miles of probably 15 other NASCAR race shops and numerous other shops

                          Comment


                          • #14
                            Re: flat sheet cowl?

                            F21 cowl is flat wrap. I have not seen a flat wrap cowl on anything else.

                            Comment


                            • #15
                              Re: flat sheet cowl?

                              OK.This is from an old thread. I need to dish my lower cowl as the flat cowl I duplicated stresses the pre-war nosebowl.






                              Bashibazouk AKA Josh Brehm
                              BL-65 #1705
                              TF #910
                              NC47~ South Oaks Aerodrome
                              EAA 1423
                              Winterville, NC

                              Comment

                              Working...
                              X