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  • Fwd Spars

    Here's some pictures of a fwd spar. Where there are 4 capstrips I used extra long 5/32 cleco's. I'll be squeezing all the fasteners, much easier on the hands. Even with careful identification of all the detail parts, assembly took some time and I got one capstrip installed wrong. The dead givaway was I could not easily install a cleco in every hole. Flipped the fay surface 180 degrees and everything lined up. Finishing these big subassemblies will be a major step forward. Per Bobs instructions I opened the wing attach holes to an interim size of .250.
    Gerry
    Patrol #30
    Attached Files

  • #2
    Nice work! Really enjoy the pictures.

    Comment


    • #3
      About 4 years ago, those spars kicked my rear end. Then a fellow EAA member and president passed away at good old age with his project (30+ years in the making) unfinished. I could see me with my lack of skill and experience being in the same situation. I had a talk with my wife and committed to a kit. So I have an impression of the work those take, and now I imagine what a blessing it would be for the home builder to have a CNC built, single piece of aluminum in place of all the cap strips and spacer bars. Some day I think Mark will be able to make those available and they will be popular.
      Brooks Cone
      Southeast Michigan
      Patrol #303, Kit build

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      • #4
        For what its worth, I'm finding that instead of 1.5 diameter (.2343) for length beyond the material thickness for the 5/32 capstrip rivets, .190 (1.25) works much better. For areas where there are 4 capstrips plus a .032 web plus primer, I take a 5-12 (.750) and cut it back to .730 and it gives me a perfect shop head both in dianeter and height per my rivet guage. So for me 1.25 for all the spar rivets is the magic number. This is for the -4 and -5 diameter rivets. I continue to be vigilant and test each rivet length on a test coupon, but so far so good. All this is for squeezed rivets, driven rivets may vary. Squeezing rivets is a very slow but satisfying experiencing. Some days I only get a dozen rivets set but I keep at it every day. The end is in sight.
        Gerry
        Patrol #30

        Comment


        • #5
          I found metric screws on Amazon that took the place of 5/32 clecos.
          capscrew.jpg
          support.jpg I was paranoid about not setting a curve into spar while riveting. Vans RV builders talk about it on their forums. Bob had a specific order of riveting too.
          I riveted as Bob said and added supports everywhere.



          I had to remove rivets that should never have been set. That was annoying. There are locations along the fuel tank that will support straps on the top and bottom strip. No rivets.
          There are locations at the 4130 supports that should not get rivets.

          I never found a solution. I tried leaving fasteners in those locations to remind me. It did not work; I turn off my brain while riveting and would remove fastener without thinking. I tried tape over locations that should not be riveted. It did not work. Would remove tape and promptly drive rivets. Leaving a note at that location definately does not work since I can not read while riveting.

          I would see a hole and promptly drive rivet.

          I found that I was not able to squeeze rivets by hand without ridiculously long handles. I eventually had to rivet using a c-frame.
          cframe.jpg

          I think If I had another person helping it would have been faster to use a 4x rivet gun. It just required to much coordination -for me- to handle rivet gun and bucking bar with one person.


          One last thing: It is unfortunate that they do not sell half size rivets for the larger rivets. You can buy half size in some of the smaller AD3 and AD4
          This tool is useless and a waist of money. I hate it. They should be destroyed on site.
          useless.jpg
          Of course what I did instead is stupid too:

          lathe.jpg

          Attached Files
          Last edited by sjt; 06-13-2021, 04:09 PM.
          Stan
          Austin Tx

          Comment


          • #6
            slot.jpg


            anvil2.jpg
            Did I mention that I hate AD5 rivets.

            Here is one of my many stupid inventions.
            It is called:

            My 150 lb moble, variable height, anvil for removing those stupid AD5 rivets.
            mobil2.jpg

            This is something I got from AVery:
            avery.jpg

            I got whatever this thing was supposed to be from Tractor Supply.
            tractor.jpg


            To make one of these all you need is 30 years of brake drums and brake rotors you have been hiding in back yard.
            Then you need a lenght of pipe you found in a junk yard. You took it home because you knew you could not live without it.
            Then get some roller casters for the bottom so you can slide the stupid thing around to various locations because it is now to heavy to move, and the garage floor is not level.
            Finally a back rivet c-frame kit from Avery and small piece of delron for the support on capstrip

            For the final bit you need to go to harbor freight and buy something that was supposed to be used at your neighborhood chop shop.
            set.jpg

            Since this is hardend steel you need a rose bud torch to aneal it
            torch.jpg
            And finally use a lathe to make custom punches for every rivet size you think you need to remove
            lathe.jpg

            I wont go thru the entire process of annealing hardened metal because the state of Califorina has decided that cat litter (Vermiculite) is a carcinogen. But if you have hidden a bag of cat litter in the back yard you should be able to soften metal.

            As long as you are at your hiding spot in the back yard dig out the 5 gallon bucket of used transmission fluid you will need to quench tool after heating to cherry red.
            If you have not been hiding your used oil in back yard, you might try peanut oil - but that is pricey.

            If you have not been hiding used oil in back yard you simply have not been planning ahead.
            Attached Files
            Last edited by sjt; 01-27-2023, 10:32 AM.
            Stan
            Austin Tx

            Comment


            • #7
              I get the whole AD5 rivet thing. I solved much of the "opps, should not have put a rivet in that hole" thing by not drilling a fastener hole in those locations in the first place. I agree that a rivet gun would be faster but speed is not a concern for me. I have found that persistence is far more important than speed. I was not confident I could shoot and buck a -5 by myself. Plus I will go to any length to avoid having another person touch my airframe. I do love the rivet removal tool. Well done!! I sand my rivets to length with a small disc sander. It's mindless work and I screwed up a lot of rivets getting the technique down, but I started with the longest and use the bad ones for shorter length's. It's kind of cool knowing there's someone else out there going through the same process as me.
              Gerry
              Patrol #30

              Comment


              • #8
                What they do not say when describing the process is the important stuff.
                The books say start with a rivet 1.5 diameters longer. At this point you find that you can not buy a rivet 1.5x longer. But, thinking that you will just use the next size up you give it a go.
                At this point a rivet that is only a little longer will anvil over. You then remove the rivet and tell yourself that was a one off and it will not happen again. Then you try again and it anvils over. Now, you have done it. While you hate driving a AD5 rivet you are really going to hate an AD6 rivet.

                In the end we all end up as you said. We find something that works - no matter how long or stupid - and just get on with it.

                stan
                Austin Tx p284

                p.s.
                Another example of what they do not say:
                I was keeping honey bees. The books say only work the bee hives in the middle of the day. That it. That is all the books say. Well, that was not a very good explanation.
                So, I once tried to work the bees at night. I figured they would not fly at night.
                If they get mad I can leisurely walk back to my car and they can not follow me. -During the day they some times follow me back to the car. I have to walk around the car half a dozen times to get enough spacing so that I can open the door; it is a race to get in the car without them following me in.

                I was donned up with the normal suit and face mask. What could go wrong?

                I will tell you what can go wrong. I was correct, they do not fly at night. Unfortunately for me they do crawl on the ground.
                Now, when you put on a bee suit you are protected from flying insects. It turns out you are not protected from 100s of bees crawling up your pant legs and stinging your ankles.

                So when I write my book on bees I will have a chapter "Never ever work the bees at night - Any other time of the day is fine just never at night because bees crawl on ground at night"


                And when I write my book on riveting there will be a special chapter; . I will claim that rivets must be exactly 1.5000 longer. not 1.5001. Of course if you work for Boeing and have another helper with a bucking bar you might be able to drive a longer rivet. But, definately do not try this at home by yourself.
                Last edited by sjt; 06-13-2021, 01:54 PM.
                Stan
                Austin Tx

                Comment


                • #9


                  That is the Military Specification for riveting the US Army Missile Command uses. Shop head tolerances on Table 3 on p.10 validates what you two are saying. It is quite gracious and forgiving compared to the .5D/1.5D shop head dimension I was taught.
                  Brooks Cone
                  Southeast Michigan
                  Patrol #303, Kit build

                  Comment


                  • #10
                    dont use cat litter for annealing--- use powdered lime. works great.

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