#551
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Laser
Thank you for posting your use of the laser, Jack.
I have used two different types. One shoots a single dot - vertical, horizontal and 90degrees to the horizontal. I've used it in place of a plumb bob. You can shoot up through a hole and find the spot directly above that hole on the ceiling. The other laser shoots lines. I've used it to make sure a large welding table is level. Shoot the horizontal line over the top of the table, then use a scale to measure all points on the table - from the top of the table to the laser line. It's better than using a level. I recall Kerry hanging a cheap laser from the ceiling by a string, and pointing at the sweet spot on his fixed dolly below, so that when the sweet spot was covered by metal he was working on, he'd know where to hit.
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John Ron Covell, Autofuturist books (Tim Barton/Bill Longyard) and Kent White metalshaping DVD's available, shipped from the US. Contact lane@mountainhouseestate.com for price and availability. |
#552
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Quote:
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Bob |
#553
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Laser
Bob,
When looking for a laser you have to realize there are two types. Those that broadcast a line, and those that broadcast a dot. Some, like mine, do both. I looked around, tried the ones from Home Depot but settled on a Spectra Precision 5.2XL that I bought off Amazon. I've used it in the shop, home remodeling, deck building, etc. The light really isn't bright enough for using it in the daylight, but the special glasses help. There are receivers that will receive the signal, even when you can't see it. But you have to make sure to get one that works on the same wave length as your transmitter unit. The receiver for my Spectra Precision grade laser (sits on a tripod at a construction site) will not work with the laser above. I'm very happy with my purchase.
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John Ron Covell, Autofuturist books (Tim Barton/Bill Longyard) and Kent White metalshaping DVD's available, shipped from the US. Contact lane@mountainhouseestate.com for price and availability. |
#554
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Next is the rear half. There's not much here that's difficult but it is a long, low crown panel. I started wheeling in some rough shape so I could get the location of the notch at the rear of the fin before the tail light.
The notch needs to be stretched, not shrunk. It will need extra material to lay down lower than the rest of the panel. I marked the area and hammered it in over a shot bag. I continued wheeling, bringing in some crown to the side and rolling the upper edge over. Rolling this top edge is part wheeling and part manipulating. As I'm wheeling with medium pressure from about 8" inboars to the outer edge, I'm also pulling the panel downward to move the upper edge. I left a lot of extra material when I cut this blank off the sheet. Once I got the rough shape and location established, I trimmed the edges closer to finished size. I always do this on larger panels because as you're shaping and especially with areas of deep shrinking or stretching, the shape of the outer edges will move. If the sheet is trimmed too close to finish size it can come up short in some areas. So, once I have the bulk of the shape in, I start to trim the edges in so it's a little easier to work the panel in areas like the tail light opening and the notch at the rear of the fin. There's still a lot to do on this panel but it's on its way.
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Jack Set a Goal So Big That You Can't Achieve It Until You Grow Into The Person That Can. |
#555
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Thanks
Quote:
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Bob |
#556
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The panel lays flat on the buck now, so I'll trim and tip the flanges around the tail light opening. Good so far.
Still lays down on the buck after adjusting the flange with the shrinker. Next, I tipped the flange for the bumper relief and that's when the trouble started. I now have a twist in the panel that got me so aggravated I shut it down for the day and walked away. Sheet Metal: 1 Jack:0 I came back out this morning with a somewhat better attitude and got on it again. I decided to start doing the finish work on the panel and see what developed. There is a lot of work in the area where the dip is above and ahead of the tail light opening. There is very little done elsewhere. It's a low crown panel. Along the top edge I rolled roughly six inches in, all the way through the length pulling downward as I moved toward the edge. As I was bringing in the shape across the top edge I noticed that the twist in the panel was getting a little worse. If I clamp it to the buck, the shape is good but it won't stay that way. If I release the clamps, It returns to its twisted shape which is about 2" off the buck in the lower front corner and the same at the upper rear corner. It's possible that the dip in the top edge and the roll along the length of the upper edge are causing the problem since they were partially manipulated and partially wheeled (compressed) into shape. There is internal stress in this panel and I messed around all day trying to find it. This involved some cursing (No, it involved a LOT of cursing) that I'll omit from this text, and got me pretty much nowhere. Part of the problem now is that I have tipped the lower flange and the flanges in back so I am "locked in" there. The fender begins a taper at around station #5, which is right in the middle of this panel, and narrows as it goes back toward the tail light. It doesn't rock against #4 and #6 but I could use a little more crown in this area. I don't know if that's going to help me with this internal stress problem but that will need to be done next. For now it looks like another sleepless night and the scoreboard is reading Sheet Metal:2 Jack:0 Any input would be appreciated.
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Jack Set a Goal So Big That You Can't Achieve It Until You Grow Into The Person That Can. |
#557
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Fender looks very nice. If i had your woodworking skills i would be a carpenter. I suck at buck building in wood. I would need a extra shop and more skill, Ray
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Ray |
#558
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You may need to shrink rather than stretch.
I had a locked in reverse curve giving me fits. There's a thread about it somewhere here. |
#559
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I've picked up some great tips from your thread. Have you thought about some localized heat in the area which may be a problem. Steel starts to turn color at about 400 degrees which is low from the steels point of view. Almost like heat shrink but not quite. Maybe try it on a piece of scrap. I have plenty! Let it air cool. In the past I have used a heat gun to heat a section or edge which causes it to expand to see if I need to stretch that area to get the results I am looking for. Not enough heat to be permanent but enough to see if I'm headed in the right direction. Thanx for posting
George
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George If you are afraid to fail, you will never learn |
#560
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I started doing some fine tuning today but didn't get very far. I had some other work to do but I managed to get the peaks of both halves to align and started smoothing out the rear panel. I still need to work the stress out of this rear half before I weld the two together. If I were to weld them as they are, the tension from the rear panel would transfer to the front half and cause even bigger problems.
I still feel that most of the problem comes from the dip in the peak ahead of the tail light opening. I think I'll try some heat as George suggested. That might momentarily allow the metal in that area to relax. If it does, the metal will move to a point where there is no longer enough pressure or tension to make it go any further. I'll probably need to do another shaping session in this corner but I have to find out what caused this for two reasons; first, I need to know what happened in order to repair it. Second, I have to make another one for the right side. I'd like to avoid going through this again so I need to know what caused the problem.
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Jack Set a Goal So Big That You Can't Achieve It Until You Grow Into The Person That Can. |
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