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having trouble with lower crown panel

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  • having trouble with lower crown panel

    I am making a roof section for a 280zx and it's kicking my butt, when I get my patterns and gauges to fit going say left to right then front to back becomes out of wack and vice versa, it's really frustrating because the FSP I was using just did not help one bit as it is not a complex panel "area" wise and doesn't show me what to do very well. (the gauges I was using are cardboard and I cut the shape of the cars roof on to it. The pattern is a FSP which I stopped using. I've tried the Geoff Moss/English way where you use the car as a buck and feel where it wants wheeling and that helped but still I cant get the panel exact or close to it even)

    Any input is appreciated.

    One more thing I have also tried just bending the shape in but that went horribly.

  • #2
    Bandit ...when that happens you will find that there is not enough shape on the panel so ..when making the side or front ''kent'' rail you need profiles length way and side ways
    cut your blank about one inch bigger all round on the paper pattern mark the middle ,start and end of the radius's transfer that to the blank ,then on the sand bag block those line starting from the center radius working your way to the two other lines, as you do the back off with the blows on the blending, but at all time keep the panel open while you blocking using your elbow and hands OR... block a few times then open right up, do that each time,..... what that does stop the panel curling and bending one way only ( and that is what is happening to your panel now) use the profiles to guide you while blocking and opening the panel, once the panel is close to the shape wanted (check on the car for fit). You can wheel only if you like (rather then blocking ) but the same principal applies ...bit of wheeling ,open and check if you are wheeling the panel try to keep the panel open while wheeling (stops it from curling ) remember keep you blocking close together and not to heavy
    Peter T.

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    • #3
      Several people on the "other" site telling him to use the FSP's (Peter loves FSP's btw). Totally clueless. That's why I advised Bandit to join this site.

      Peter talks a little () about why he doesn't like FSP's in this thread:

      https://ce8df029be3e-004671.vbulleti...-by-our-friend





      Last edited by Chris_Hamilton; 05-28-2020, 01:48 AM.

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      • #4
        It seems verboten here but....
        flexible shape patterns preform really poorly on low crown panels with shape in one direction.

        secondly in order for a flexible shape pattern to work the surface area must be as you want the final panel to be. If you pattern dents and rust etc those imperfections will be translated as well.

        3rd if you are making a pattern of the front of the roof from edge to edge (1 piece) your guages must be the same. It looks like you are trying to make it in 1 piece but have short guages intersecting long ones. Ie front to back guage on the horizontal roof area is being intersected by short vertical guages. Those shot guages should go up the side but across the roof (left to right) , at least further than mid way.

        That area seems better suited to a paper pattern and guages. If you usd a straight edge on a door / panel and there is curvature in one direction but not in the other. In the example of a door then there might be curved surfaces top to bottom vertically but no curvature front to back horizontally then the panel is better suited to a paper pattern than a Flexible shape pattern.

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        • #5
          i would advise against using FSP's for anything, at your age and the stage you are at, it would be more beneficial for you to learn how to make and read traditional paper patterns, along with profile gauges. peter has done some very informative video's regarding making and reading paper patterns
          thanks neil

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          • #6
            Originally posted by Jaymce View Post
            It seems verboten here but....
            flexible shape patterns preform really poorly on low crown panels with shape in one direction.

            secondly in order for a flexible shape pattern to work the surface area must be as you want the final panel to be. If you pattern dents and rust etc those imperfections will be translated as well.

            3rd if you are making a pattern of the front of the roof from edge to edge (1 piece) your guages must be the same. It looks like you are trying to make it in 1 piece but have short guages intersecting long ones. Ie front to back guage on the horizontal roof area is being intersected by short vertical guages. Those shot guages should go up the side but across the roof (left to right) , at least further than mid way.

            That area seems better suited to a paper pattern and guages. If you usd a straight edge on a door / panel and there is curvature in one direction but not in the other. In the example of a door then there might be curved surfaces top to bottom vertically but no curvature front to back horizontally then the panel is better suited to a paper pattern than a Flexible shape pattern.

            I said why use FSP at all ...
            After the disaster on each piece on the E type Jaguar bonnet, our friend has NOT learned his lesson, just take a look at the E type jaguar front guard this time, and check out how far the edge off the guard is when he places the East to west pattern .. the dam thing must be at least 1 inch off at the end ...AGAIN too full !!! then he turns around and say....[ quote]... this happens nearly every time you make a panel ..... I say ....WHAT A LOT OF CRAP !! and the proof is??? Every single panel he has made with the FSP ended up too full
            By the way when making a guard or rear quarter with a wheel arch, 99 times out of 100 the wheel arch needs to be stretched ... What does he do ? He shrink the crap out of it . Further more... when making a return shape one needs to stretch the edges..... what does he do ? He shrinks them ???????? When wheeling one must have little pressure at each time (unless blocking with the wheel) the idea of little pressure is to be able to feel the panel and stretched little by little wheel with the line of site, (and some time... yes.... cross wheeling is necessary ) every panel our friend has done has not been wheeled with the line of site once.... always the other way

            Please guys.... I am not been critical ..any one can work and do what they like I just like people to read about these things and learn properly
            Last edited by Peter Tommasini; 05-28-2020, 03:02 PM.

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            • #7
              Peter,
              not endorsing just pointing out where some problems lie from what I could see.

              Jay

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              • #8
                Colin, my suggestion would be to go through the videos here on MSH. I appreciate your ambition but would suggest a different strategy. I'm not assuming your youth means you're not capable of doing good work. I've learned the beneifits of better mastering smaller tasks before pursuing larger ones, whether it's me being the novice or the teacher.

                Set the roof project aside for a little bit. One video here showed the exercise of using the English wheel to deliberately crown/shape the sheet, then return it to flat. There's a reason why young professionals and apprentices practice this exercise over and over and over again until its second nature. Not very exciting, but it works. As your fluency grows, so can the size of your panel.

                This is comparable to welding fluency. How's your welding? It will be a drag to wheel up a great roof and then find big challenges when the time come to install it. At the point, you'll be glad to have some expertise to easily make another roof panel..

                like you e mentioned, I've normally made cardboard or chipboard pattern. Others use their Lancaster shrinker & stretcher to shape a strip of sheet metal into a homemade version of a sweep to use as the same type of pattern, that would also be a great exercise for you, because it will provide you more practice making metal Into the shape you need it to be. Label them well and start building your collection of patterns. I plan to make more of these in the future.

                You're at a very important stage of your path as a craftsman. Learning and mastering the basics is necessary. Otherwise, improper methods learned now will become enduring obstacles to future progress. My expertise is not as a metalshaper, but from parallel professional skill sets that require almost mind-numbing amounts of boring repetive practice before fluency is realized. Many come anxious to do the great results work without ever mastering the basics. It's really tough for many of them to unlearn bad ways to achieve what they seek. So I'm working on mastering the same basics I suggest to you.

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                • #9
                  You have found the best place in the world to learn about metal-shaping Bandit.😃

                  Have a look in Peter's online shop and buy his DVD's and buy Davis Gardiner's DVD as well. Best thing I ever did was start there,

                  Cheers Charlie

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