I have been working up to installing 18 Ga. steel interior in my sedan. I built a substructure out of 1x2x .06 rectangular tubing. For the tranny hump I used 1x1x.125 angle iron and .125x2"b flat bar to build a skeleton for the hump. Here is what that looked like: I then used some cardboard to work out patterns for my sheetmetal. Here are some shots of my cardboard interior: I then began with the major floorboard piece and transferred the measurements to the 18 ga. and cut out the pattern. I trimmed everything for a nice fit and was ready for the exciting stuff, bead rolling. I needed a step along the one edge because the angle iron frame for the tranny hump sat on top of the 1x2. I also wanted some beads between the 1x2 cross braces to make the piece look interesting and stiffen things. Here is a pic of what I made: I'm pretty satisfied with the fit and look of the panels. However they don't lay flat on the substructure like they did in there pre-beaded state. The panel is somewhat potatoe chipped from the forming operation. So my questions are: 1. Is it normal for the steel to deform like this because of the beading/stepping operation? 2. Is there some kind of stress relieving operation that should be taken before I weld the panels in? This is my first attempt at putting a sheetmetal interior in a car. I am a bit uneasy that I rolled beads to prevent oil canning of the flat panel and now it is pre-oil canned. I will be forcing the oil can down to install and weld the panel in. Hope someone has some past experience and knowledge to share,
I believe its caused by the dies in your bead roller. To alleviate the warping when rolling beads they need flat rollers on either side of the bead die to hold the steel flat. Without them the steel will warp, I had the same issue on a 'professionally' made A RPU rear tub section. That make sense? You say this is a first time? Damn man, you have done well, wish I could get stuff to come out like that on a first attempt, my hats off to you. Doc.
To minimize warpage you can: Pre-stretch the area to be beaded. Minimize the size and depth of your beads. In your case (floor) I don't think I would sweat it very much - straighten them as much as practical and then tack them in.
I'm speaking from no experience, here, but: On a recent episode of Two Guys Garage on Speed Channel, Bryan Fuller (a 'name' in the industry) english-wheel'd a panel before he rolled some beads, just to resolve the problem you've discovered. It's a little less than intuitive to understand that bead rolling will stretch metal in the vicinity of the bead and that that stretch needs to be relieved by pre-stretching it, but there you are. If some of the metalworks gurus drop by here, they'll be able to 'splain it better. What to do now? No clue. I'd probably clamp it down and weld it from the center out, but I'd have no idea what I'm doing... Cheers -- Gary "I have yet to see any problem, however complicated, which, when you looked at it in the right way, did not become still more complicated. -- Paul Anderson
When you roll a bead in a piece of metal, it pulls the metal along the path of the bead. In other words you have shrunk the panel along the bead. To solve this problem you need to prestretch the panel along the intended path of the bead. You can do this on an english wheel, or you could just hammer on dolly along the path before beading. This will take a little trial and error to perfect.Another option is to slice the panel from the end of the bead to the edge of the panel, this should relieve the stress, then just weld the slice back up.
Looks good, as for the warping from the beads, yeah it happens, run the panels over your "english knee" till sorta flat, clamp them dowm and weld away! You can prestretch to eliminate the warp, but its gonna warp when you weld it anyway. It shouldnt oilcan after its installed. If it does post up more pics and we will help you get it right.
I have never had much of a problem with panels oil canning after bead rolling but I usually run a much smaller bead than you have there. I don't see it being much of a problem since you have framework underneath. Put something heavy on top and spot weld to the frame from below, move the weight around. Seems if you went only half as deep with the dies you wouldn't get anywhere as much oil canning. Looks like your floor is coming along nicely!
Thanks for the advice everybody. Ok KiwiKev I tried some more beads in a different panel and took your advice on easing up on the bead depth. Here is the panel that covers the rear kickup: These large panels are a bitch,bear, motherf***er to handle in the bead roller. But the shallow beads didn't seem to cause much distortion. Do you just make a single pass when you roll the bead? I made some simple panels for the side of the kickup: As I was fitting these pieces I started to think it might be nice to create an access panel to get to the suspension and what not below the kickup. I was thinking of a removable trapezoidal piece like this: I have never made a panel like this and haven't been able to locate any examples from other peoples work. One thought is to cut out the opening and spot weld a flange to the back side of the panel that the removable piece could be screwed to. This would keep everything flush since the flange would be one metal thickness back. Does anyone have different ideas or suggestions to how they might create the access panel?
I don't have anything to add on the original question, But i have a question about your Trans Tunnel . Why is it so Tall ?
I imagine it has something to do with the air ride set up that you can see in the second pic, looks like it is going to sit on its rockers when aired out
rather than cutting a hole in the side panel, why not make the side panel removable? You could drill/tap the skeleton for some 10/32 screws and run with it.
When Datinman did my sheet metal interior, I asked him if he needed me to go buy some poster board... he just looked at me kinda funny.
For those interested in what is being built here is a link to the build thread: http://www.jalopyjournal.com/forum/showthread.php?t=147848 If anyone has any links to slick sheetmetal fab's/installs please post them up. I am very interested to see what others are doing.
seems to me that you could cut your opening a bit smaller and step-flange the edge, then cut a new piece to fit as your cover-panel?...I don't think coke-bottle new guy likes you much, btw...heh
The Jalopy Journal
