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Elevator counterweight casting

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  • #16
    I have question about how to cover over the counterbalance: Is it preferable to have the fabric glued directly to the lead? Or would it be better to have the lead recessed slightly so the fabric drums above it?

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    • #17
      I have never glued to the lead. I leave the lead recessed. Mark

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      • #18
        Based on our experience it was kinda hard not to glue to the lead if you don't recess it. You'll probably want to put some reinforcing tape or something on the lead as the fabric will be too close to that surface to not be concerned about wear. They say if you can push on the fabric and touch something under it, you need protection at that point. When we ironed it the fabric tightened up enough to lay flat on the lead and when we applied the polyspray brush coat, it stuck it down to the lead and any imperfections showed up at that time. What you see ( or even don't see ) there you will really see when you apply the silver coat.) (The dangers of Polyspray is a whole other thread.) Our lead was not recessed below the tubing. We sandwiched the tube with wood and clamps and poured the lead so routing out for a recess I think would be a good idea.

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        • #19
          As I'm painting parts the thought occurred to me to check the balance of the elevators before doing the topcoat. I'm glad I did. Even though I used Russ Erb's method for calculating the amount of lead (according to his CD, his turned out "perfect"), it's not enough. So I'll have to sand off the primer on the underside, open up the fabric and somehow attach a weight to the back of the existing weight. Bob B. suggested drilling a hole in the front tube that forms the elevator tip and adding lead in there but I don't thing it would be enough. Anyway, put in more than you think you need. According to my kit log I put in 4lbs. 5 would have been much better. You have been warned! 20211203_132714.jpg20211203_153639.jpg

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          • #20
            965CA615-D6CE-4DEC-BBB2-0FC4241D91D3.jpg I tacked two thin sheets of metal to my elevator and then brazed around the edges being very careful to keep everything below the surface of the elevator tubes. Filled with molten lead. The holes are where I added anchor bolts brazed and ground flush. Fabric will not touch this surface. I calculated the amount of lead to balance and it turns out I was within 1 oz of what the factory is now pouring. Stewart covering with paint applied is .8 oz per square foot.

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            • robcaldwell
              robcaldwell commented
              Editing a comment
              I also had to add weight to my elevators after they were covered. I used lead wool and epoxy that I packed into the leading edge tube. Worked out well.

          • #21
            I used oratex so my fabric weight was pretty much fixed. If I painted I might have erred on the side of too much counter weight, and drill thru the fabric on the bottom side to remove excess lead weight, and patch the fabric.

            I think Bob might be right. Figure out how much lead you need to add and the volume it requires(I would use lead shot, even though I cast my lead balance weights).Drill the leading edge of the elevator balance. Pour in a little lead, inject some epoxy, a little more lead, a little more epoxy. The screw/bolt should hold the new weight in place. I would do it in the front corner of the tube.

            If the current counter weight is very close, i.e. it is just barely under balanced, I would probably just accept it. Just my opinion.
            Last edited by svyolo; 12-03-2021, 10:58 PM.

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